RCU Installation, Operation & Maintenance...

(©December, 2006)

RCU Installation, Operation & Maintenance Manual

(©December, 2006)


MODEL NOMENCLATURE

OHS-040-RCU-O

RCU = Remote CondensingUnit

Nominal Capacity in1,000’s of BTU/H

O ( ) = Outdoor System I ( ) = Indoor SystemOHS Series

(©December, 2006)


1.0 Introduction ....................................... 1-11.1 General ...................................................... 1-11.2 Product Description ................................... 1-11.2.1 Capabilities and Features .......................... 1-11.2.2 Application Ranges .................................... 1-11.2.3 General Design .......................................... 1-21.2.4 Safety Features ......................................... 1-21.3 Product Warranty ...................................... 1-31.3.1 Extended Compressor Warranty ................ 1-41.4 Safety ........................................................ 1-51.4.1 General ...................................................... 1-51.4.2 Safety Summary ........................................ 1-5

2.0 Installation ......................................... 2-12.1 Receiving the Equipment. .......................... 2-12.2 Site Preparation ......................................... 2-12.3 Rigging ...................................................... 2-12.4 Mounting/Placement .................................. 2-12.5 Piping Connections .................................... 2-22.5.1 Refrigerant ................................................. 2-22.6 Utility Connections .................................... 2-42.6.1 Main Power/Control Wiring ........................ 2-42.7 System Settings and Adjustments ............. 2-72.7.1 R-22 Refrigerant Charging Procedures ....... 2-72.7.2 R-407C Refrigerant Charging Procedures ... 2-82.7.3 Low/High Pressure Limit Switch ................ 2-92.7.4 Head Pressure Controls ........................... 2-102.7.4.1 Condenser Fan Cycling............................ 2-102.7.4.2 Condenser Fan Speed ............................. 2-102.7.4.3 Flooded Head Pressure Control ............... 2-102.8 Refrigerant Characteristics ....................... 2-102.8.1 Pressure/Temperature Settings ................ 2-102.8.2 Saturated Refrigerant Pressure Tables ......2-11

3.0 Start-Up/Commissioning .................. 3-13.1 Operation ................................................... 3-13.2 Step by Step Start-Up Instructions ............. 3-13.3 Operational Description.............................. 3-1

TABLE OF CONTENTS4.0 Maintenance/Repairs ....................... 4-14.1 Periodic General Maintenance ................... 4-14.1.1 General ...................................................... 4-14.1.2 Compressor ............................................... 4-14.2 Troubleshooting ......................................... 4-24.3 Field Service .............................................. 4-54.3.1 Leak Detection .......................................... 4-54.3.2 Leak Repair ............................................... 4-54.3.3 Refrigerant Piping ...................................... 4-54.3.4 General Common Repairs/

Component Replacement ........................... 4-54.3.4.1 Compressor Failure ................................... 4-5

5.0 Product Support Group ................... 5-15.1 Technical Support ...................................... 5-15.2 Obtaining Warranty Parts .......................... 5-15.3 Obtaining Spare/Replacement Parts .......... 5-1

List of FiguresFigure 1- Typical Layout RCU-O (Outdoor Unit) ..... 1-2Figure 2- RCU Mounting ........................................ 2-2Figure 3- Piping Installation ................................... 2-3Figure 4- RCU Field Wiring .................................... 2-4Figure 5- Sample Nameplate ................................. 2-5Figure 6- Electric Box ........................................... 2-6

Appendix A - FormsChecklist for Completed Installation .........................A-1Periodic General MaintenanceChecks and Service Checklist ..................................A-2

Appendix B - GlossaryDefinition of Terms and Acronyms ............................B-1

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1.0 INTRODUCTION

1.1 GeneralCongratulations, the Remote Condensing Unit (RCU)covered by this manual is designed and manufacturedby Stulz Air Technology Systems, Inc. (SATS) usingthe latest, state-of-the-art control technology. Recog-nized as a world leader, SATS provides precisioncooling systems with the highest quality craftsmanshipusing the finest materials available in the industry. Theunit will provide years of trouble free service if installedand maintained in accordance with this manual.Damage to the unit from improper installation, opera-tion or maintenance is not covered by the warranty.

This manual contains information for installation,operation, maintenance, troubleshooting and repair.STUDY the instructions contained in this manual.They must be followed to avoid difficulties. Spare partsare available from Stulz Air Technology Systems toinsure continuous operation. Using substitute parts orbypassing electrical or refrigeration components inorder to continue operation is not recommended andwill VOID THE WARRANTY. Due to technologicaladvancements, components are subject to changewithout notice.

SATS RCU systems are designed to reject heat fromrefrigerant based cooling equipment. Any use beyondthis is deemed to be not intended. SATS is not liablefor any damage resulting from improper use. The RCUsystem is designed to be installed outdoors unlessotherwise noted on the equipment nameplate.

1.2 Product DescriptionSATS Remote Air Cooled Condensing Units are designedto be the most compact and reliable RCU systems in theindustry. The unit is an air-cooled, heat rejection condens-ing system with horizontal air discharge.The RCU is self contained in a light weight, corrosionresistant aluminum cabinet designed for mounting toa horizontal surface. The cabinet houses the com-pressor, condenser coil, fan assembly, sight glassand receiver (optional). The electrical controls are inan integrally mounted, weather proof enclosure whichis isolated from the rest of the equipment. There areseveral cabinet sizes based on the capacity of theunit. Refer to the installation drawing supplied withyour unit for the layout and dimensions of the cabinet.

The cooling capacity in BTU/Hr will depend on the unitsize which can range from 12,000 to 60,000 BTU/Hr.The condensing system is a closed-loop circuit inwhich refrigerant is continuously circulated by a

pressure differential created by the compressor. Thecompressor is designed to increase refrigerantpressure to a level sufficiently high for it to be cooledand condensed into liquid by the effect of ambient airbeing drawn over the condenser coil.Outdoor RCU’s use fan cycling for low ambient headpressure control down to 0°F. Variable fan speedcontrol is used for operation in low ambient tempera-tures down to -20F. Flooded head pressure control isused for low ambient temperatures down to -30°F.SATS RCU systems are designed to operate witheither R22 or R407C refrigerant. Refer to the unitnameplate to identify the model number and whichrefrigerant is used with your unit.

NOTESATS RCU systems are strictly for non-resi-dential applications.

Operation of the RCU is controlled by a 24 VAC inputsignal from a system controller provided with the refrigera-tion equipment.

1.2.1 Capabilities and FeaturesAll Aluminum Cabinet Construction.Aluminum Fin Copper Tube Coil Construction.Vibration Isolation of Compressor.Direct drive Fan Motor Equipped WithPermanently Lubricated Motor Bearings.Removable Lid Allows Access To All Components.Compact Profile With Recessed Control Enclosure.

1.2.2 Application RangesSATS RCU systems are designed for operation withinthe following ranges:Outdoor Temperature Range:Fixed Fan Cycling Control ...................... 0ºF to 95ºF.Variable Fan Speed Control ................... -20ºF to 95ºF.Flooded Head PressureControl ............ -30ºF to 95ºF.

Operating Voltage: VAC Input per unit nameplate +/- 10%.Max. Piping Length; Refrigeration Equipment to RCU:150 ft equivalent length.Max. Level Drop; Refrigeration Equipment to RCU:20 ft (when condenser is below the evaporator).

Storage Conditions: ............................... -30ºF to 105ºF.

NOTEDamage or malfunction to the unit due tostorage or operation outside of these rangeswill VOID THE WARRANTY.

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1-2

1.2.3 General DesignFigure 1 depicts a typical layout of an outdoor RCUand identifies the major components.

1.2.3.1 CompressorThe compressor is mounted inside the unit on vibrationabsorbers to eliminate noise and vibration duringoperation. Compressors are equipped with crankcaseheaters to prevent refrigerant from migrating into thecompressor during the off cycle, permitting smootherstart-ups.

1.2.3.2 Condenser CoilThe condenser coil is rated at the capacity indicatedby the unit model number. It is a copper tube, alumi-num finned coil.

1.2.3.3 Fan AssemblyFor outdoor applications the RCU uses a propellertype fan with a direct drive motor rated for continuousoperation. It is equipped with an aluminum, multi-blade fan. The motor is equipped with internal overloadprotection and is protected from over current by amotor starter protector located in the electric box.

1.2.3.4 Electric BoxThe electrical components are protected in a recessedenclosure located on the side of the unit. The electricbox has a removable front access panel which is safetyinterlocked with the service disconnect switch prevent-ing the panel from being removed when the switch is inthe “On” position. The switch must be turned “Off” togain access to the electrical components.

1.2.3.5 Circuit Breakers/Motor Start ProtectorsIndividual overload protection is provided by circuitbreaker(s), and motor start protectors. These switcheswill open to de-energize a failed component if electricaloverload conditions are encountered. They must bemanually reset once the overload condition is cleared.

1.2.3.6 Receiver

An optional receiver is provided for storage of excessrefrigerant in the refrigeration cycle. Typically used onoutdoor RCU’s for cold weather applications, the receiveris provided for units using flooded head pressure control.

1.2.4 Safety FeaturesOutdoor RCU units are provided with a factorymounted, service disconnect switch as standard. Theservice disconnect switch electrically isolates the unitduring routine maintenance. The handle of the switchmay be locked in the “Off” position to prevent unautho-rized operation. The RCU system incorporates state ofthe art component protection with the use of motorstart protectors and circuit breakers.

Low and high-pressure switches are provided for therefrigeration circuit. The pressure switches are non-adjustable encapsulated control switches. If a highpressure switch is tripped for any reason, it must bemanually reset. The cause for tripping of the highpressure switch must be determined. The low pressureswitches are reset automatically. These pressureswitches are installed as safety devices and will helpprevent compressor failure or other serious damage tothe system.

Figure 1- Typical Layout RCU-O (Outdoor Unit)

COIL

FAN ASSEMBLY

COMPRESSOR

RECIEVER (OPTIONAL)

ELECTRIC BOX

DISCONNECT SWITCH

Internal Layout- Top ViewFront Isometric View

SERVICE DISCONNECT SWITCH

ELECTRIC BOX ACCESS PANEL

AIR INLET

AIR OUTLET

MOUNTING BASE

REMOVABLE LID

(©December, 2006)


1-3

2-Year Standard Limited Warranty:Stulz Air Technology Systems, Inc., warrants to the original buyer of itsproducts that the goods are free from defects in material and workmanship. Stulz Air Technology Systems, Inc.’s obligation under this warranty is torepair or replace, at its option, free of charge to the customer, any part orparts which are determined by Stulz Air Technology Systems Inc. to bedefective. The warranty is in effect for 24 months from date of shipment if acompleted Warranty Registration and Start Up Form is submitted to Stulz AirTechnology Systems, Inc. within 90 days from shipment. In the event that acompleted start-up form is not received by Stulz Air Technology Systems, Inc.within 90 days from shipment, the company’s obligation will be for a period of12 months from date of shipment. Parts replaced under warranty are war-ranted for a period of 90 days from shipment or for the remainder of the unitwarranty period, whichever is greater.

Stulz Air Technology Systems, Inc.’s warranty does not cover failures causedby improper installation, abuse, misuse, misapplication, improper or lack ofmaintenance, negligence, accident, normal deterioration including wear and tear,or the use of improper parts or improper repair as determined by SATS. Thiswarranty does not include costs for transportation, costs for removal or reinstal-lation of equipment or labor for repairs or replacement made in the field.

THIS OBLIGATION AND LIABILITY OF STULZ AIR TECHNOLOGY SYS-TEMS, INC. UNDER THIS WARRANTY DOES NOT INCLUDE LOSSES,DIRECT OR INDIRECT, FOR INCIDENTAL OR CONSEQUENTIAL DAM-AGES. THIS WARRANY IS IN LIEU OF ALL OTHER WARRANTIES,EXPRESS OR IMPLIED, INCLUDING WARRANTIES OR MERCHANTABIL-ITY AND FITNESS FOR A PARTICULAR PURPOSE, AND THERE ARE NOWARRANTIES THAT EXTEND BEYOND THE DESCRIPTION ON THE FACEHEREOF.

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1.3 Product WarrantySATS offers a two year standard limited warranty as stated below. Additionally an extended warranty may bepurchased on the unit's compressors. Consult the factory to verify if the extended compressor warranty waspurchased for your system. The extended compressor warranty as stated on the next page will be sent with yourunit and should be retained for future reference.

(©December, 2006)


1-4

Optional Limited Extended Warranty (5 Years Total)Stulz Air Technology Systems, Inc., warrants to the original buyer of its product thatthe compressor(s) listed below are warranted for parts replacement (not includinglabor) for extended period of 4 years from the date of expiration of the standardequipment warranty.

Stulz Air Technology Systems' warranty does not cover failures caused by improperinstallation, abuse, misuse, misapplication, improper or lack of maintenance, negli-gence, accident, normal deterioration including normal wear and tear, or the use ofimproper parts or improper repair as determined by SATS.

This warranty does not include costs of transportation, cost for removal or reinstalla-tion of equipment or labor for repairs or replacement made in the field.

The obligation and liability of Stulz Air Technology Systems under this warranty doesnot include losses, direct or indirect, for incidental or consequential damages.

Compressor Serial No.: __________________________________

Unit Model No.: __________________________________

Unit Serial No.: __________________________________

Stulz Air Technology Systems Job No.: __________________________________

End User: __________________________________

Date: __________________________________

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1.3.1 Extended Compressor Warranty

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1-5

1.4 Safety1.4.1 GeneralStulz Air Technology Systems, Inc. uses NOTESalong with CAUTION and WARNING symbols through-out this manual to draw your attention to importantoperational and safety information.

A bold text NOTE marks a short message in theinformation to alert you to an important detail.

A bold text CAUTION safety alert appears withinformation that is important for protecting yourequipment and performance. Be especially careful toread and follow all cautions that apply to your applica-tion.

A bold text WARNING safety alert appears withinformation that is important for protecting you fromharm and the equipment from damage. Pay veryclose attention to all warnings that apply to yourapplication.

A safety alert symbol accompanies a generalWARNING or CAUTION safety statement.

A safety alert symbol accompanies an electricalshock hazard WARNING or CAUTION safety state-ment.

1.4.2 Safety SummaryThe following statements are general guidelinesfollowed by warnings and cautions applicablethroughout the manual.

Prior to performing any installation, operation, mainte-nance or troubleshooting procedure read and under-stand all instructions, recommendations and guide-lines contained within this manual.

CAUTION All maintenance and/or repairs must be per-formed by a journeyman, refrigeration mechanicor an air conditioning technician.

CAUTION Never lift any component in excess of 35 poundswithout help. If a lifting device is used to move aunit ensure it is capable of supporting the unit.

CAUTION Do not allow the unit to swing while suspendedfrom a lifting device. Failure to observe this warn-ing may result in injury to personnel and dam-age to the equipment.

CAUTION Do not allow anyone under the equipment sus-pended from a lifting sling.

WARNING High voltage is used in the operation of tjhisequipment. Death on contact may result ifpersonnel fail to observe safety precautions.

CAUTION When working on electrical equipment, removeall jewelry, watches, rings, etc. Keep one handaway from the equipment to reduce the hazardof current flowing through vital organs of the body.

CAUTION Always disconnect the main power supply tothe equipment at the main power disconnectswitch before beginning work on the equipment.A lock-out tag-out procedure should be followedto ensure that power is not inadvertently recon-nected.

CAUTION Equipment may contain components subject toElectrostatic Discharge (ESD). Before attempt-ing to mount or service these electronic devices,ensure you have no charge built up by touchinga ground source. When possible, use a wrist-grounding strap when working on or near elec-tronic devices.

CAUTIONNever work on electrical equipment unless an-other person who is familiar with the operationand hazards of the equipment and competent inadministering first aid is nearby.

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CAUTION All personnel working on or near equipmentshould be familiar with hazards associated withelectrical maintenance. Safety placards/stick-ers have been placed on the unit to call atten-tion to all personal and equipment damage haz-ard areas.

CAUTION Ensure the unit is properly phased. Improperphasing can cause severe damage to the com-pressor.

WARNING Refrigerant (R-22 or R-407C) is used with thisequipment. Death or serious injury may result ifpersonnel fail to observe proper safety precau-tions. Great care must be exercised to preventcontact of liquid refrigerant or refrigerant gas, dis-charged under pressure, with any part of thebody. The extremely low temperature resultingfrom the rapid expansion of liquid refrigerant orpressurized gas can cause sudden and irrevers-ible tissue damage.

As a minimum, all personnel should wear ther-mal protective gloves and face-shield/goggleswhen working with refrigerant. Application of ex-cessive heat to any component will cause ex-treme pressure and may result in a rupture.

Exposure of refrigerant to an open flame or avery hot surface will cause a chemical reactionthat will form carbonyl chloride (hydrochloric/hy-drofluoric acid); a highly poisonous and corro-sive gas commonly referred to as PHOSGENE.In its natural state, refrigerant is a colorless, odor-less vapor with no toxic characteristics. It isheavier than air and will disperse rapidly in awell-ventilated area. In an unventilated area, itpresents a danger as a suffocant.

Always refer to the manufacturer's MSDS pro-vided with the unit.

WARNING Avoid skin contact or inhaling fumes from anyacid formed by burn out of oil and refrigerant.Wear gas mask if area is not thoroughly venti-lated. Wear protective goggles or glasses toprotect eyes. Wear rubber gloves to protecthands. Use care to avoid spilling compressorburnout sludge. If sludge is spilled, clean areathoroughly.

WARNING When performing soldering or de-soldering op-erations, make certain the refrigeration systemis fully recovered and purged and dry nitrogen isflowing through the system at the rate of notless than 1-2 CFM (.03 - .06 M³/minute).

CAUTION Certain maintenance or cleaning proceduresmay call for the use and handling of chemicals,solvents, or cleansers. Always refer to themanufacturer's Material Safety Data Sheet(MSDS) prior to using these materials. Cleanparts in a well-ventilated area. Avoid inhalationof solvent fumes and prolonged exposure of skinto cleaning solvents. Wash exposed skin thor-oughly after contact with solvents.

CAUTION Do not use cleaning solvents near open flame orexcessive heat. Wear eye protection when blow-ing solvent from parts. The pressure-wash shouldnot exceed 30 psig. Solvent solutions should bedisposed of in accordance with local and stateregulatory statutes.

CAUTION The unit must be kept in its normal installed po-sition. If the unit is not kept level and vertical,damage to the unit's compressor will result.

(©December, 2006)


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2.0 INSTALLATION

2.1 Receiving the EquipmentYour RCU system has been tested and inspected priorto shipment. To ensure that your equipment has beenreceived in excellent condition, make a visual inspec-tion of the equipment immediately upon delivery.Carefully remove the shipping container and allprotective packaging. Open the access doors andthoroughly inspect the unit interior for any signs oftransit-incurred damage. If there is shipping damage, itmust be noted on the freight carrier's delivery formsBEFORE signing for the equipment. Any freight claimsMUST be done through the freight carrier. SATS shipsall equipment FOB factory. SATS is not liable for anyequipment damage while in transit. SATS can assist inthe claim filing process with the freight carrier. Shouldany such damage be present, notify the SATS ProductSupport Group prior to attempting any repairs. Refer tosection five of this manual for instructions.

Check the equipment against the packing slip to see ifthe shipment is complete. Report all discrepancies toappropriate authority.

A Data Package has been sent with your unit. Itcontains this manual, system drawings, applicableMSDS’s and other applicable instructions based onthe configuration and options of your unit. The datapackage has been placed in your unit in a clear plasticenvelope. These documents need to be kept with theunit for future reference.

2.2 Site PreparationSATS RCU systems are designed with easy serviceaccess in mind. Install the RCU in a secure locationwhere the unit cannot be tampered with and the mainpower disconnect switch cannot be inadvertentlyturned off. Allow access to the unit for routine opera-tion, servicing and for necessary maintenance. Referto the installation drawing provided with your unit forthe dimensions of the RCU.

NOTE

Working clearance requirements need to be es-tablished prior to the mounting of the unit. Referto local and national electrical codes.

NOTE

Equipment must be level to operate properly.

2.3 RiggingThe RCU system is designed to be kept level in avertical position. Move the unit with a suitable devicesuch as a forklift or attach an overhead lifting sling,supporting the unit from the mounting base. Use anappropriate capacity lifting device that can safelyhandle the weight of the equipment. Weight tables areprovided on the installation drawing provided with yourunit. If using an overhead lifting device, utilize liftingbars that exceed the cabinet width so as to avoidcrushing the sides of the unit. Remote CondensingUnits are shipped on a skid to facilitate moving prior toinstallation. Units should always be stored in a drylocation prior to installation.

CAUTION

Units must be kept level and in the vertical posi-tion when lifting to prevent damage to the unit.

2.4 Mounting/PlacementOutdoor, propeller fan RCU’s are designed for mount-ing to a flat surface. Install the RCU in a securelocation with adequate space for accessing compo-nents for installation, maintenance and repair proce-dures. The refrigeration components on outdoorpropeller fan RCU’s are accessed through the top byremoving the lid and from the back by removing therear air discharge panel. The electric box is accessedfrom the side of the unit. Locate the unit where thecoils are not likely to draw dirt and debris into the coilfins.

Condensing units must not be located in the vicinty ofsteam, hot air or fume exhausts. The clearance aroundthe unit should be at least 1 times (1x) the unit’s widthto ensure adequate airflow to the coil. Space multipleunits so that hot condensing exhaust air is notdirected toward the air inlet of an adjacent unit. Avoidareas where heavy snow will accumulate at air inletand outlet openings. If possible, make use of terrainfeatures such as trees and buildings to provide ashaded location. This will minimize the solar load onthe unit. Avoid ground level sites that are accessible tothe public.

Install a solid base, capable of supporting the weight ofthe equipment. Reference the installation drawing forthe non-charged system weight. The base should beat least 2 inches higher than the surrrounding gradeand 2 inches larger then the dimensions of the con-densing unit base. (See Figure 2.)

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Refrigerant lines for split systems must be sizedaccording to the piping distance between the evapora-tor and the condenser. Each valve, fitting and bend inthe refrigerant line must be considered in this calcula-tion. Refer to the following chart for standard equivalentlengths, in feet, of straight pipe.

If the RCU is installed above the evaporator, thesuction line should include a P-trap at the evaporator.

Oil traps must be included every 20 feet in the verticalrisers and the refrigerant lines must be sloped ¼ inchfor every 10 feet in the horizontal lines to ensure properoil return to the compressor. (See Figure 3.)

If the RCU is installed below the evaporator, thesuction line should include an inverted trap the heightof the evaporator coil. This prevents migration of liquidrefrigerant to the compressor during off cycles.

All suction lines should be insulated to preventcondensation from forming.

Insert the factory provided vibration isolators betweenthe RCU and the base as shown in Figure 2 to reducethe amount of vibration transmitted to the mountingsurface. Secure the unit with fasteners (field suppliedby others) so that the system will not move duringoperation.

BUSHING

MOUNTINGBRACKET

FLAT WASHER

LOCK WASHER

FLAT WASHER

HEX NUT

HEX NUT

MOUNTING STUD

Figure 2- RCU Mounting

2.5 Piping Connections2.5.1 RefrigerantSplit air-cooled systems require a field installedcopper suction line and copper liquid line between theRCU and the evaporator. Refer to the refrigerationdiagram provided with your unit for piping details. RCUunits are shipped with a dry nitrogen holding charge.

All refrigeration piping should be installed with hightemperature soldered joints. Use standard refrigerationpractices for piping supports, leak testing, dehydrationand charging of the refrigeration circuits. The refrigera-tion piping should be isolated from the building by theuse of vibration isolating supports. To prevent tubedamage when sealing openings in walls and to reducevibration transmission, use a soft flexible material topack around the tubes.

Clear all pipe connections of debris and prepare theconnections for soldering. Use only "L" or "K" graderefrigerant copper piping. Be careful not to allowsolder/piping debris to get inside refrigerant lines.Silver solder containing a minimum of 15% silver isrecommended. Dry nitrogen should be flowing throughthe tubing while soldering at a rate of not less than 1-2CFM (.03 - .06 M3/minute).

Equivalent Length (ft) of Straight PipeOD (In.) Globe Angle 90º 45º Tee Tee

Line Size Valve Valve Elbow Elbow Line Branch

1/2 9.0 5.0 0.9 0.4 0.6 2.0

5/8 12 6.0 1.0 0.5 0.8 2.5

7/8 15 8.0 1.5 0.7 1.0 3.5

1-1/8 22 12 1.8 0.9 1.5 4.5

1-3/8 28 15 2.4 1.2 1.8 6.0

1-5/8 35 17 2.8 1.4 2.0 7.0

2-1/8 45 22 3.9 1.8 3.0 10

2-5/8 51 26 4.6 2.2 3.5 12

3-1/8 65 34 5.5 2.7 4.5 15

3-5/8 80 40 6.5 3.0 5.0 17

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Refer to the following pipe size charts for recom-mended pipe sizing.

*Equivalent Ft. accounts for the linear pipe length as well asequivalent length of Valves, Elbows & Tee’s as shown in theprevious chart.

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Recommended Suction Line Sizes

(For R-22 or R-407C Refrigerant)

Evaporator To RCU- Equivalent Ft*

Capacity 50' or less 100' or less 150' or less BTU/Hr H V H V H V

12,000 5/8 5/8 5/8 5/8 7/8 5/8

18,000 7/8 7/8 7/8 7/8 7/8 7/8

24,000 7/8 7/8 7/8 7/8 7/8 7/8

36,000 7/8 7/8 1-1/8 7/8 1-1/8 7/8

42,000 1-1/8 1-1/8 1-1/8 1-1/8 1 1/8 1 1/8

48,000 1-1/8 1-1/8 1-1/8 1-1/8 1 1/8 1 1/8

60,000 1-1/8 1-1/8 1-1/8 1-1/8 1 3/8 1 1/8

Recommended Liquid Line Sizes

(For R-22 or R-407C Refrigerant)

Model No./ RCU To Evaporator- Equivalent Ft.*Total Unit 50' 100' 150'Capacity BTU/Hr or less or less or less

012 / 12,000 3/8 1/2 1/2018 / 18,000 3/8 1/2 1/2024 / 24,000 3/8 1/2 1/2036 / 36,000 1/2 1/2 1/2042 / 42,000 1/2 5/8 5/8048 / 48,000 1/2 5/8 5/8060 / 60,000 1/2 5/8 5/8

H= Horizontal Run; V= Vertical Run

NOTEVertical runs are based on a total rise of 30 equivalentfeet. For longer sizes, individual calculations must bemade. Sizes assume the use of single risers; doublerisers may be necessary.

Figure 3- Piping Installation

PITCH IN DIRECTION OF REFRIGERANT FLOW

(SUCTION & LIQUID LINES)

TRAP IN BOTTOM OF COLUMNWITH MINIMUM TRAP DEPTH POSSIBLE

TRAP EVERY 20 FEET WITH MINIMUM TRAP DEPTH POSSIBLE

PITCH 1/4" FOR EVERY 10 FEET OF RUN

REMOTECONDENSING UNIT

INVERTED TRAP

EVAPORATOR ORAIR HANDLER

PITCH IN DIRECTION OF REFRIGERANT FLOW

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2.6 Utility Connections2.6.1 Main Power And Control WiringSystems equipped with an RCU require field wiringbetween the RCU and the system controller. (SeeFigure 4.) The RCU unit is provided with main powerand control terminal positions for connection of thefield-wiring (supplied by others). It is important toidentify the options that were purchased with the unitin order to confirm which field connections are re-quired. Refer to the electrical drawing supplied with theunit to determine the total number of interconnectingconductors required for your system.

The RCU unit is available in the following voltageconfigurations:

208-230 VAC 1-phase 208-230 VAC 3-phase 277 VAC 1-phase 460 VAC 3-phase 575 VAC 3-phase

Verify that the main power supply coincides with thevoltage, phase and frequency information specified onthe system nameplate. The supply voltage measuredat the unit must be within ±10% of the voltage speci-

fied on the nameplate. (See Figure 5.) The nameplatealso provides the full load amps (FLA), the current thatthe unit will draw under full design load, the minimumcircuit ampacity (MCA) for wire sizing, and the maxi-mum fuse or HACR (Heating, Air Conditioning, Refrig-eration) breaker size (MAX FUSE/CKT BKR) for circuitprotection. The unit's nameplate is located inside thecabinet within the electrical box.

Pilot hole openings for the conduit are located in theside of the electric box. A label stating "MAIN POWERINPUT" is in close proximity. The main power wires areterminated at the line side of the service disconnectswitch located within the electric box. A separateequipment ground lug is provided within the electricalbox for termination of the earth ground wire. (SeeFigure 6.)

The installer must also wire control conductors fromthe terminal board within the RCU unit to the systemcontroller. The number of control conductors neededwill vary depending on the type of control being usedwith your equipment. Refer to the electrical drawingsupplied with your unit to determine the correctquantity of control conductors needed and for theproper wire terminations.

Figure 4- RCU Field Wiring

REMOTE CONDENSING UNIT

WITH NFPA 70, N.E.C.)

INTERCONNECTING FIELD WIRING(TO BE INSTALLED IN ACCORDANCE

MAIN POWER SUPPLY

L2

L3

L1

CONTROL WIRES(QUANTITY VARIES)

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WARNINGHigh voltage is used in the operation of thisequipment. Death on contact may result ifpersonnel fail to observe safety precautions.

WARNINGVerify power is turned off before making connec-tions to the equipment.

NOTE

All wiring must conform to local and national elec-trical code requirements. Use of copper conduc-tors only is required. Wiring terminations maybecome loose during transit of the equipment;therefore, it is required to verify that all wiringterminations are secure.

It is important to note that the control transformersupplied with the equipment is sized and selectedbased upon the expected load for the system.

CAUTION

Do not connect any additional loads to the sys-tem control transformer. Connecting additionalloads to the factory supplied control transformermay result in overloading of the transformer, whichwill cause the transformer circuit breaker to trip.

Figure 5- Sample Nameplate

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2-6

The number call outs in Figure 6 coincide with thenumbered items listed below.

1. Power Switches/Motor Starter Protectors2. Service Disconnect Switch3. Ground Lug4. Access Panel5. Control Circuit/Crankcase Heater Circuit Breaker6. Control Interface Terminals7. Disconnect Switch Handle (Must be in off position

to remove access panel)

CAUTION Improper wire connections will result in thereverse rotation of the fan and compressor andmay eventually result in damage to thecompressor. To correct this problem, ex-change any two of the incoming main powerwires at the main power circuit breaker. DoNOT rewire the unit's individual components.

Figure 6- Electric Box(Shown with access panel removed)

1

2

5

4

6

73

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2.7 System Settings and Adjustments2.7.1 R-22 Refrigerant Charging Procedures

NOTE

Refrigerant charging must be performed by ajourneyman, refrigeration mechanic or an air con-ditioning technician.

2.7.1.1 Remote Air-Cooled Split SystemsRemote air-cooled units come equipped with a factorydry nitrogen holding charge, which must be removedbefore piping and charging the unit.

PREPARING SYSTEM FOR CHARGING

1. Once all connections have been made, pressurizethe system to 150 psig with dry nitrogen. Leaksmay be detected by observing the standingpressure.

2. After ensuring there are no leaks, relieve pressureand evacuate the system. Pull a vacuum of 50microns or less using the suction and dischargeservice ports and the service port of the receiver (ifapplicable). Hold the vacuum for 2 hours. Ensureno portion of system has been isolated from theevacuation process (liquid, suction or dischargelines).

CAUTION A proper vacuum must be drawn on the refriger-ant system prior to charging. If this is not donethe refrigerant will combine with the moisture inthe pipes to form an acid that will eventuallycause compressor failure.

FINE TUNING THE SYSTEM CHARGE

2.7.1.1.1 0ºF Fan Cycling and -20ºF VariableSpeed Control

The following instructions are for charging systemswith condenser fan cycling or variable speed controlusing R-22 refrigerant.

1. Bleed air from hoses and "break" the systemvacuum by supplying R-22 vapor. Supply R-22

vapor until the pressure is raised to about 50psig. This small holding charge allows the lowpressure switch to “make” throughout the pro-cess of fine tuning the system charge

WARNING Do not add liquid R-22 refrigerant to thesuction side of the system.

2. Start the system and use the controller to lowerthe room temperature set-point 3-5°F below actualroom temperature. This will ensure the coolingmode stays on during the charging procedure.

CAUTION An adequate heat load must be supplied to theunit to ensure a proper charge.

3. Supply R-22 vapor to the suction port until theliquid line sight glass is cleared of all bubbles.

4. After the unit has stabilized, the liquid line sightglass should be clear and the discharge pressureshould be a minimum of 200 psig. A superheatreading should be taken near the feeler bulb fromthe thermal expansion valve, with the temperature-measuring device being well insulated. The idealsuperheat temperature is 12-15°F. Maximumallowable superheat temperature is 20°F.

5. A sub cooling reading should be taken on theoutput side of the condenser, with the tempera-ture-measuring device being well insulated. Thesub-cooling temperature should be approximately10-20ºF.

NOTE

Under cold climate conditions it is recommendedto do the following:

6. Block off the intake air to the condenser coil withcardboard until a constant discharge pressure(225-280 psig) can be obtained. This will lower thepossibility of overcharging and avoid the occa-sional bubbles that may appear in the sight glassduring fan cycling. (For units with fan cycling only.)

7. Ensure the crankcase heater is operational bychecking the amperage.

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CAUTION Remove the blockage to the air intake of thecondenser coil.

9. Fill out applicable blocks of Warranty Registrationand Start-Up Checklist.

2.7.1.1.2 -30ºF Flooded Head Pressure Control

The following instructions are for charging systems withflooded head pressure control using R-22 refrigerant.

1. Bleed air from hoses and "break" the systemvacuum by supplying R-22 liquid to the service valveof the receiver until the receiver is full. Then supplyR-22 vapor to the suction port until the pressure israised to about 50 psig (low pressure switchmakes).

2. Start the system and use the controller to lowerthe temperature set-point 3-5°F below roomtemperature. This will ensure cooling remains onduring charging procedure.

CAUTION An adequate heat load must be supplied to the unit toensure a proper charge.

3. After starting the system, immediately supplyR-22 vapor to the suction port until the liquid linesight glass has cleared of all bubbles.

4. Raise the discharge pressure to 300-325 psig andhold it constant by blocking the air intake of thecondenser.

5. Once the discharge pressure has stabilized for 5 to10 minutes, additional refrigerant R-22 vapor mustbe added to the suction port until the "float ball" inthe level indicator of the receiver begins to float.

CAUTION Remove the blockage to the air intake of the con-denser.

6. Take a superheat temperature reading near thefeeler bulb from the thermal expansion valve. Theideal superheat temperature is 12-15°F. Maximumallowable superheat temperature is 20°F.

7. Ensure that the crankcase heater is operational bychecking the amperage.

8. Fill out applicable blocks of Warranty Registrationand Start-Up Checklist.

2.7.2 R407C Refrigerant Charging ProceduresR-407C is a blended refrigerant recognized for beingsafer for the environment. Refrigerants that are multi-component blends have component parts with differentvolatilities that result in a change in composition andsaturation temperature as evaporation and condensa-tion occur. Typically the composition of R-407C vaporis different than that of R407C liquid within a con-tained system. The composition of liquid R-407Crefrigerant remains relatively constant, however, therefrigerant vapor tends to separate into its componentparts even when circulating. When charging a systemusing blended refrigerants, it is essential that thecomposition of the refrigerant is maintained. Toensure correct composition, introduce R-407C into thesystem in liquid form rather than vapor form. Cylinderswhich are not provided with dip tubes should beinverted to allow only liquid refrigerant to charge thesystem. Keeping the temperature of the cylinderbelow 85°F will help to maintain the correct refrigerantcomposition while the cylinder is emptied.

CAUTION POE oil is used in systems with R-407Crefrigerant. POE oil quickly absorbs moisturewhen exposed to air. High POE oil moisturelevels react with refrigerant to form acid, whichresults in system contamination. Keep entiresystem sealed as much as possible andminimize exposure of POE oil to outside air.Familiarize yourself with the charging proce-dures discussed in section 2.7.1 of thismanual. Instead of adding R-22 vapor to thesuction port as described under “PreparingSystem For Charging”, the initial charge willbe performed by introducing R-407C liquid tothe discharge side of the compressor.

PREPARING SYSTEM FOR CHARGING

1. With all the system piping connections made,perform a dry nitrogen leak detection test on thesystem. Using dry nitrogen only, pressurize the

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2-9

system to 150 psig. Since there is no refrigerantin the system to detect, leaks may be detectedby observing the standing pressure.

2. After ensuring there are no leaks, evacuate thesystem to 50 microns and hold the vacuum for 2hours.

3. Break the vacuum by supplying R-407C liquid tothe discharge port near the compressor until thepressure is raised to about 50 psig. This smallholding charge allows the low pressure switch to“make” through the process of fine tuning thesystem charge.

FINE TUNING THE SYSTEM CHARGE

4. Disconnect the refrigerant cylinder from thedischarge side of the compressor and connect itto the suction side.

5. Start the system and use the controller to lowerthe room temperature setpoint 3-5°F below actualroom temperature, ensuring cooling remains onas the unit is charged.

6. Allow the discharge pressure to rise to 225-280psig and hold it constant. On cool days it may benecessary to restrict the airflow across thecondenser coil to raise the pressure.

7. Slowly meter R-407C liquid refrigerant through thesuction side while watching the sight glass to clearof bubbles.

CAUTION Add liquid refrigerant slowly to prevent the refrigerantoil from “washing out” of the compressor.

8. Take a superheat temperature reading near thefeeler bulb from the thermal expansion valve, withthe temperature-measuring device being wellinsulated. The ideal superheat temperature is 12-15°F. Maximum allowable superheat temperatureis 20°F.

9. While monitoring the sight glass, take a sub-cooling temperature reading on the output side ofthe condenser. The sub-cooling temperatureshould be 10-20°F.

10. If necessary, add liquid refrigerant to maintainadequate sub-cooling temperature.

2.7.2.1 R407C Flooded Head Pressure ControlIn units with R-407C refrigerant using flooded headpressure control, a receiver is provided to store therefrigerant during the time the condenser is not usingthe extra refrigerant charge. Once a clear sight glasshas been achieved, additional refrigerant must beadded to the receiver.

A level indicator is located on the side of the receiverto assist the service technician in charging the airconditioning system. The proper charge can bedetermined by viewing the position of the “float ball”while the unit is running. If the “float ball” is positionedat the bottom of the sight indicator, additional refriger-ant charge is needed. When the “float ball” reachesthe top of the indicator, the unit is fully charged.

2.7.3 High/Low Pressure Limit SwitchSATS RCU units are equipped with hermeticallysealed high-pressure and low-pressure switches.These switches are preset by the manufacturer andcannot be adjusted. The high pressure switch willopen to disengage power to the compressor contactorif the discharge pressure rises above a specificpressure. The high-pressure switch opens at 410 psigand has a manual reset. If a compressor was disableddue to high pressure conditions, a manual reset of thehigh pressure safety switch is required.

The Low pressure switch will open to disengage powerto the compressor contactor if suction pressure dropsbelow a specific pressure. The system controllershould ignore the absence of this signal during thecold start delay period after starting of a compressor.The low-pressure switch opens at 10 psig (± 4) andcloses at 32 psig (± 5) and has an automatic reset.

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2.7.4 Head Pressure Controls

2.7.4.1 Condenser Fan CyclingThe condenser fan cycling switch senses refrigerantdischarge pressure and turns on the condenser fan asrequired to maintain allowable condenser pressures.This is a high-pressure differential control switch withSPST contacts and an automatic reset. The switchactivates the condenser fan contactor, cooling thecondenser to maintain the condensing temperaturewhen the discharge pressure rises to 275 psig.

Factory setting: Contacts close on a pressure rise to275 psig and open at 205 psig. Setpoint range is 170to 275 psig. Differential is non-adjustable and set at 70psi.

2.7.4.2 Condenser Fan SpeedSATS RCU units may be equipped with variable speedcondenser fan motor control to maintain head pressurecontrol. The fan speed control is a continual modula-tion of the motor’s speed. The condenser fan speedcontroller monitors the refrigerant discharge pressureand varies the condenser fan speed as required tomaintain allowable condenser pressures. The fanspeed controller is set to maintain condensing tem-perature at 125°F and requires no adjustments.

2.7.4.3 Flooded Head Pressure ControlFlooded head pressure control is designed to maintainhead pressure during low ambient temperature condi-tions. A head pressure control valve and a receiver isprovided in the refrigeration circuit to back up liquidrefrigerant into the condenser coil.

When the receiver pressure drops the valve divertsdischarge gas away from the condenser. The liquidflow from the condenser is restricted which allowsliquid to back up in the condenser. Flooding thecondenser reduces the area available for condensingthus raising the condensing pressure. As the pressureincreases, the valve diverts the discharge gas to thecondenser, which will allow liquid flow from the con-denser to the receiver.

When using this method of head pressure regulationthere must be enough refrigerant in the system toensure adequate charge at the lowest expectedambient temperature that the system will be operating.

A receiver is used to store the refrigerant during thetime the condenser is not using the extra refrigerantcharge. The head pressure control valve does notbegin to allow refrigerant to pass to the receiver untilthe discharge pressure is at least 180 psig. This valverequires no adjustment.

2.8 Refrigerant Characteristics2.8.1 Pressure/Temperature SettingsThe following chart is provided to assist with thenormal settings of the system for R-22 and R407Crefrigerant. Where applicable, minimum and maximumsettings are given along with normal operating pres-sures.

Pressure/Temperature Settings For R-22 & R407CNormal Min. Max.

Sub-cooling°F 10 5 20

Superheat°F 15 10 20

Condensing Temperature °F 125 105 140

Suction Pressure (psig) 70 58 84

Opens Closes

Low Pressure Switch (psig) 10 32

High Pressure Switch (psig) 410 Manual Reset

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2.8.2 Saturated Refrigerant Pressure TablesThe following refrigerant vapor pressure tables areprovided for reference for R-22 and R407C refrigerant.

(SaturatedVapor)

(SaturatedLiquid)

R-22 RefrigerantTemp. Pressure (°F) (psig)

20 43.222 45.524 47.826 50.228 52.6

30 55.132 57.734 60.436 63.138 65.9

40 68.742 71.744 74.746 77.848 81.0

50 84.255 92.760 10265 11170 122

75 13280 14485 15690 16895 182

100 196105 210110 226115 242120 260

125 278130 296135 316140 337

R-407C RefrigerantTemp. Pressure (°F) (psig)

Superheat

20 37.022 39.124 41.326 43.628 46.0

30 48.432 50.934 53.536 56.238 58.9

40 61.742 64.644 67.646 70.748 73.8

50 77.1

Sub-cooling

95 206100 222105 239110 257115 275

120 294125 315130 336135 358140 381

BubblePoint

DewPoint

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3.0 START-UP/COMMISSIONING

3.1 OperationFor new installations, ensure the unit is ready tooperate by going through the Checklist for CompletedInstallation, located in Appendix A, prior to start-up.

NOTE

A Warranty Registration and Start-Up Checklistis provided with the unit data package. It shouldbe completed during start-up and sent to SATS.This checklist should be used as a guideline foritems that need to be confirmed during start-up.

Start-up must be performed by a journeyman, refrig-eration mechanic or an air conditioning technician.

3.2 Step by Step Start-Up Instructions

CAUTION Prior to initial start-up (only when main powerhas been disconnected for 12 hours or longer),allow at least ten 10 minutes, (two (2) hours isrecommended), with main power reconnected.This will allow sufficient time for the crankcaseheaters to evaporate any liquid that may havemigrated to the compressor crankcase. Whenthis procedure is completed, the unit is ready tobe run.

1. Replace all equipment removed prior to performingstart-up checks.

2. Apply power to the RCU system at the mainpower disconnect switch.

NOTE

The compressor may have a time delay on start-up.

The refrigeration circuit must be tested at start-up.Refer to the separate controller operation instructionssent with your unit in the data package.

3. Test cooling operation by adjusting the tempera-ture setpoint at the system controller. The com-pressor should come on and the suction lineshould gradually drop in temperature.

3.3 Operational Description1. Compressor starts; condenser fan starts.

NOTE

RCU’s equipped with condenser fan cycling orcondenser fan speed conrol, have a delay afterthe compressor starts for the minimum pressureto be reached to start the fan motor.

2. Refrigerant flowing to the RCU unit in the form of alow pressure (and low temperature) gas, entersthe compressor where it is compressed into a hightemperature, high pressure gas.

3. The refrigerant then flows to the condenser coil.The high temperature, high-pressure gas from thecompressor is cooled by the flow of air through thecondenser coil and is changed into a low tempera-ture, high-pressure liquid.

4. For cold weather applications using flooded headpressure control and/or full floating hot gasbypass, the low temperature high-pressure liquidrefrigerant flows to a receiver. The receiver acts asa storage tank for the liquid refrigerant that is notin circulation.

5. The refrigerant flows through a liquid sight glass.This device indicates the presense of air, moistureand state of the refrigerant in the system.

6. The low temperature high pressure liquid refriger-ant then flows to the air handler or evaporatorwhere it removes heat and evaporates into a gas.

7. The refrigerant gas is then drawn back to thecompressor and the cycle is repeated.

8. A pump down cycle prevents liquid refrigerant fromcondensing in the evaporator during off cycles.

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4.0 MAINTENANCE/REPAIRS

4.1 Periodic General MaintenanceSystematic, periodic general maintenance of theremote condensing unit is recommended for optimumsystem performance. General maintenance shouldinclude, but is not limited to the following: tighteningelectrical connections, cleaning the interior of the unit,inspecting the unit’s components visually. Checkinglevel of refrigerant and ensuring no moisture is in therefrigerant .

Use copies of the Periodic General MaintenanceChecklist in this manual (see Appendix A) to recordperiodic general maintenance inspections. Forassistance, contact the SATS Product Support Group.Ensure adherence to all safety statements whileperforming any type of maintenance.

WARNING Turn off power to the unit at the main power dis-connect switch unless you are performing teststhat require power. With power and controls en-ergized, the unit could begin operating automati-cally at any time.

Hazardous voltage will still be present even with theunit turned off at the controller. To isolate the unit formaintenance, turn off power at the main power discon-nect switch.

Always disconnect main power prior to performing anyservice or repairs. To prevent personal injury, stay clearof rotating components because automatic controlsmay start them unexpectedly.

This unit employs high voltage equipment with rotatingcomponents. Exercise extreme care to avoid acci-dents and ensure proper operation.

4.1.1 GeneralMaintenance access to the remote condensing unit isthrough the removable panel on top of the unit. Exam-ine the areas around the air inlet and outlet grills, fans,motors and coils. Use a vacuum cleaner with a softbristle brush to clean dirt from components. Clean thecoil of all debris that will inhibit airflow. This can bedone with a soft brush and compressed air or with acommercial coil cleaner. Check for bent or damaged

coil fins and repair as necessary. On outdoor units donot permit snow to accumulate on or around the RCUin the winter. Check all refrigerant lines and capillariesfor vibration isolation and support as necessary. Checkall refrigerant and lines for signs of leaks.

• Examine all wiring for signs of chafing, looseconnections or other obvious damage. (Quarterly)

• Examine brackets, motor mounts and hardware forloose or missing parts or other damage. (Quarterly)

• Clean accumulations of dust and dirt from allinterior and exterior surfaces. (Quarterly)

CAUTION The compressor crank case heater is ener-gized as long as power is applied to the unit. Ifthe service switch is turned off for long periodsdo not attempt to start a condensing unit until2 hours after applying power. This allowsenough time for all liquid refrigerant to bedriven out of the compressor. This is espe-cially important at low ambient conditions.

4.1.2 CompressorThe refrigerant compressor and its drive motor arehermetically sealed. The compressor crankcase has alifetime supply of oil and the drive motor has perma-nently lubricated sealed bearings. Check the refriger-ant charge using the sight glass while the unit isrunning. If low on charge, check for refrigerant leaks.

WARNING Phosgene, a deadly, poisonous gas, is gener-ated when refrigerant is exposed to flame. Al-ways ensure adequate ventilation during refrig-eration repairs.

This equipment should be serviced and repaired by ajourneyman or a qualified refrigeration technician only.

Always recover all refrigerant prior to any systemrepairs, failure to do so may result in system overpressurization and rupture.

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4-2

SYMPTOM PROBABLE CAUSE RECOMMENDATION

Unit Fails to Start a. Incorrect phasing or voltage. Correct phase or voltage input.

b. Power failure. Check power source, power inlet andfuses. Check control cables andconnections.

c. Overload protection tripped. Check for cause of overload and re-setcircuit breaker(s) or motor starter(s).

Control is Erratic Wiring improperly connected or Check wiring against schematicbroken. diagram.

Condenser Head Pressure a. Non-condensable gas or air in the Reclaim system, pull 50 micron vacuumtoo High system. and recharge. Install new drier/strainer.

b. Low condenser airflow. (Indicated by Open air passages. Clean coil. Checkexcessive warm air leaving the condenser fan(s).condenser fan).

c. Overcharge of refrigerant. Reclaim excess refrigerant from system.

d. Condenser fan not operating. 1. Check main voltage power source tounit.

2. Check fan motor start protector,contactor, fan cycling switch or fan speedcontroller.

3. Check pressure/temperature operatingswitches and motor. Replace as needed.

e. Condenser pressure regulating Adjust to obtain correct pressure. valve setting too high.

Condenser Head Pressure a. Loss of refrigerant (indicated by Locate and repair leak. Rechargetoo Low bubbles in sight glass). system.

b. Condenser fan controls not set Adjust or repair controls.properly.

4.2 Troubleshooting

WARNING Turn off all power to the unit before conducting any troubleshooting procedures, unless the procedure specifi-cally requires the system to operate. Keep hands, clothing and tools clear of the electrical terminals androtating components. Ensure that your footing is stable at all times.

(©December, 2006)


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Noisy Compressor a. Expansion valve stuck in open Check operation of the expansion valveposition (abnormally cold suction line). and superheat.

b. Broken compressor valve Replace compressor.(compressor knocking, suctionpressure rises faster than 2lbs/minafter shutdown).

c. Worn or scarred compressor Replace compressor.bearings.

d. Liquid slugging. 1. Ensure expansion valve is not stuck inopen position

2. System overcharged. Reclaim excessrefrigerant.

e. Compressor not properly Phase correctly at main power source.phased. DO NOT REWIRE COMPRESSOR.

Head Pressure Too High a. Low condenser airflow. (Indicated by Open air passages. Clean coil. Checkexcessive warm air leaving the condenser fan(s).condenser fan).

b. Air or other non-condensible gas Reclaim system and recharge. Install ain system new drier strainer.

c. Overcharge of rerigerant. Reclaim excess refrigerant from system.

d. Condenser fan not on. Check main voltage power source to unit.Check fan motor start protector, contactor,fan cycling switch or fan speed controller.

Suction Pressure too Low a. Expansion valve stuck in the open Repair or replace valve.position (indicated by abnormally coldsuction line).

b. Low charge, flash gas in liquid line Locate leak and repair. Recharge(indicated by bubbles in sight glass). system.

c. Clogged drier/strainer (feels cool to Replace with new drier/strainer.the touch).

d. Obstructed expansion valve (indicat Replace valve.ed by loss of capacity).

e. Loss of control fluid from expansion Replace valve or control head.valve control head (indicated bybubbles in the sight glass).

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Compressor Fails to Start a. Temperature setpoint too high. Adjust to desired temperature.

b. Compressor internal protector Check compressor for short circuit oris open. ground.

c. Complete loss of refrigerant charge Locate and repair leak. Recharge(low pressure safety switch). system.

d. Condenser pressure too high (high Check condenser for obstructions.pressure safety switch). Re-set high pressure switch.

e. Minimum off time has not expired. Wait for time to expire.

System Short of Capacity a. Low refrigerant (indicated by Check for leaks Repair and rechargebubbles in sight glass). system.

b. Expansion valve stuck or Remove valve and clear obstruction orobstructed (short cycling or replace valve.continuous running).

c. Clogged drier/strainer (feels cold). Replace with new drier/ strainer.

Compressor Short Cycles a. Low line voltage causing Check power source for cause of lowcompressor to overheat. line voltage.

b. Lack of refrigerant. Check for leak. Repair and rechargesystem.

c. Dirty or icy evaporator/heat Defrost and clean evaporator/heatexchanger. exchanger.

Erratic Fan Operation Dirty or blocked condenser coil. Clean coil or remove blockage.

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4.3 Field ServiceIt may be necessary to perform repairs on the refrig-eration system. If field repairs are necessary, thefollowing procedures apply:

NOTE

Do not attempt to make repairs without theproper tools.

4.3.1 Leak DetectionSeveral methods can be used to detect a leak in therefrigeration system. The most modern and easiestmethod is to use an electronic leak detector. Followthe manufacturer’s directions and any leak can bequickly located. A second method is to use soapbubbles. Apply a solution of soapy water with a brushor sponge to the joints and connections in the refrig-eration lines. A leak in the lines will cause bubbles toform.

NOTE

Halogen leak detectors are ineffective with R-407C refrigerant because unlike R-22 refriger-ant, R-407C does not contain chlorine.

4.3.2 Leak RepairWhen a leak is located, properly reclaim the remainingrefrigerant charge before attempting repairs. Adjacentpiping must be thoroughly cleaned by removing allpaint, dirt and oily film. Use wire brush, sandcloth orsandpaper and wipe the area with clean, dry cloths.Protect nearby parts from heat damage by wrappingwith water-soaked cloths

4.3.3 Refrigerant PipingWhen replacing components within the cabinet of theunit, the following consumable materials are recom-mended: Use Silfos alloy for copper-to-copper (pipingdischarge or suction line repairs). Silver solder (Stay-Silv #45) and flux are to be used on copper-to-brassor copper-to-steel repairs. For liquid line repairs at thedrier, strainer, sight glass, or expansion valve, use a95 % tin to 5 % antimony solder with flux.

When component replacement is complete, removeall traces of flux. After any repair, pressure check thesystem, checking for leaks prior to recharging thesystem.

4.3.4 General Common Repairs/Component Replacement

4.3.4.1 Compressor FailureThe compressor is the most important component ofthe RCU. Numerous safety devices are provided toprotect the compressor from failing.

If a compressor failure has occurred, determinewhether it is an electrical or a mechanical failure. Anelectrical failure will be indicated by the distinctpungent odor once the system has been opened. If aburnout has occurred, the oil will be black and acidic.A mechanical failure will have no burned odor and themotor will attempt to run, an abnormal or excessivenoise may be present.

An analysis of the oil is the only way to ensure theproper procedure for cleaning the refrigerant system.Acid test kits are available from several manufactur-ers for measuring the acid level in the oil. These arecapable of making accurate acid measurements, butif they are not available, a check of the oil by sightand smell can give a quick indication if contaminationremains in the system. Since refrigeration oils vary incolor, a sample of the new oil in the replacementcompressor should be removed prior to installation andsealed in a small glass bottle for comparison pur-poses. If the oil has been exposed to refrigerant, thebottle should not be tightly capped, since the residualrefrigerant may create a high pressure if tightly sealedand exposed to high temperature.

CAUTION Avoid touching or contacting the gas and oil withexposed skin. Severe burns will result. Use longrubber gloves in handling contaminated parts.

All electrical connections should be checked to besure that they are tight and properly made. Check allcircuit breakers, contactors and wiring. The contactorshould be examined and replaced if contacts are wornor pitted.

If there is acid in the oil, there has been an electricalfailure which has caused the compressor motor toburn out. The acid diffuses throughout the refrigerationsystem and must be removed by using a burnout filterkit before a new compressor is placed in service. Notonly must the compressor be replaced, but also theentire refrigeration circuit must be cleaned of the

(©December, 2006)


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harmful contaminants left by the burnout. See section4.3.4.1.2 (Burn-Out/Acidic Cleanup) for the propercleaning procedure.

CAUTION Damage to a replacement compressor causedby improper system cleaning constitutes abuseunder the terms of the warranty. This will VOIDTHE COMPRESSOR WARRANTY. Always con-sult the factory prior to replacing the compres-sor.

If there is no acid in the oil, there has been a mechani-cal failure. See section 4.3.4.1.1 (Standard Cleanout)for the proper cleaning procedure.

CAUTION POE oil is used in systems with R-407C refrig-erant. If a replacement compressor is provided,ensure that it is filled with POE oil before install-ing.

4.3.4.1.1 Standard Cleanout Procedure

CAUTION Avoid touching or contacting the gas and oil withexposed skin. Severe burns will result. Use longrubber gloves in handling contaminated parts.

NOTE

Cleaning operations must be performed by a jour-neyman, refrigeration mechanic, or air condition-ing technician.

1. Turn off power to the unit at the main powerdisconnect switch.

2. Remove the burned-out compressor and install thenew compressor.

3. Remove the liquid line drier and install an over-sized liquid line filter-drier (one size larger than thenormal selection size).

4. Evacuate the system according to standardprocedures. Normally, this will include the use of ahigh-vacuum pump and a low-vacuum microngauge for measuring the vacuum obtained.

5. Recharge the system.6. Turn on the power at the main power disconnect

switch and start the system.

4.3.4.1.2 Burn-Out/Acidic Cleanup ProcedureNOTE

Cleaning operations must be performed by a jour-neyman, refrigeration mechanic, or air condition-ing technician.

1. These systems should be cleaned using thesuction line filter-drier method.

2. Turn off power to the unit at the main powerdisconnect switch.

3. Remove the burned-out compressor and install thenew compressor.

4. Install a suction line filter-drier designed for acidremoval.

5. Remove the liquid line drier and install an over-sized liquid line filter-drier (one size larger than thenormal selection size).

6. Check expansion valve, sight glass and othercontrols to see if cleaning or replacement isrequired.

7. Evacuate the system according to standardprocedures. Normally, this will include the use of ahigh-vacuum pump and a low-vacuum microngauge for measuring the vacuum obtained.

8. Recharge the system through the access valve onthe suction line filter-drier.

9. Turn on power at the main power disconnectswitch and start the system.

10. The permanently installed suction line filter-drierpermits small-system cleanup to be completed inone service call. The pressure drop across thesuction line filter-drier should be measured duringthe first hour of operation. If the pressure dropbecomes excessive, the suction line filter-driershould be replaced (See Sporlan Bulletin 40-10, formaximum recommended pressure drop (PSI) forsuction line filter drier).

11. In 24 hours, take an oil sample. Observe the colorand test for acidity. If the oil is dirty or acidic,replace the suction line filter-drier.

12. In 2 weeks, examine oil to determine if anothersuction line filter-drier change is necessary.

(©December, 2006)


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5.0 PRODUCT SUPPORT GROUP

SATS provides to its customers a Product SupportGroup (PSG) which not only provides technicalsupport and parts but the following additional services,as requested: performance evaluations, start-upassistance and training.

5.1 Technical SupportThe SATS Product Support Group (PSG) is dedicatedto the prompt reply and solution to any problemencountered with a unit. Should a problem developthat cannot be resolved using this manual, you maycontact PSG at (240) 529-1399 Monday throughFriday from 8:00 a.m. to 5:00 p.m. EST. If a problemoccurs after business hours, dial the page number(301) 414-4514 and follow the steps below:

1. Wait for the dial tone.

2. Dial your telephone number (including area code).

3. Press the pound (#) key.

4. Wait for a busy signal.

5. Hang up the telephone.

One of our service technicians will return your call.When calling to obtain support, it is vital to have thefollowing information readily available, (information isfound on unit's nameplate):

• Unit Model Number (OHS-XXX-XXX-X)

• SATS Item Number (123456)

• Unit Serial Number (1234567)

• Description of Problem

5.2 Obtaining Warranty PartsWarranty inquires are to be made through the ProductSupport Group (PSG) at (240) 529-1399 Mondaythrough Friday from 8:00 a.m. to 5:00 p.m. EST. Aservice technician at SATS will troubleshoot thesystem over the telephone with a field service techni-cian to determine the defect of the part. If it is deter-mined that the part may be defective a replacementpart will be sent UPS ground. If the customer requeststhat warranty part(s) be sent by any other method thanUPS ground the customer is responsible for theshipping charges. If you do not have established creditwith SATS you must give a freight carrier accountnumber or accept COD (freight only).

A written (or faxed) purchase order is required onwarranty parts and must be received prior to 12:00p.m. for same day shipment. The purchase order mustcontain the following items:

• Purchase Order Number• Date of Order• SATS Stated Part Price (obtained from PSG)• Customer Billing Address• Shipping Address• Customer's Telephone and Fax Numbers• Contact Name• Unit Model No., Serial No. & SATS Item No.

The customer is responsible for the shipping costincurred for shipping the defective part(s) back toSATS. Return of defective part(s) must be within 30days at which time an evaluation of the part(s) isconducted and if the part is found to have a manufac-turing defect a credit will be issued.

When returning defective part(s) complete the ReturnMaterial Authorization Tag and the address labelreceived with the replacement part.

See SATS Standard Warranty located in section oneof this manual.

5.3 Obtaining Spare/Replacement PartsSpare and replacement parts requests are to be madethrough the Product Support Group (PSG) by fax (301)620-1396, telephone (240) 529-1399 or E-mail([email protected]). Quotes are given for specifiedlisted parts for a specific unit.

SATS accepts Visa and MasterCard. SATS mayextend credit to its customers; a credit applicationmust be prepared and approved (this process couldtake one week).

A 25% minimum restocking charge will be applied onreturned stocked parts that were sold as spare/replacement parts. If the returned part is not a stockeditem, a 50% restocking charge may be applied.Additionally a Return Material Authorization Number isrequired when returning parts. To receive credit forreturned repair/replacement parts, the parts must bereturned to SATS within 30 days of the purchase date.Spare part sales over 30 days old will be consideredfinal and the parts will remain the sole property of theordering party.

(©December, 2006)


APPENDIX A - FORMSStulz Air Technology Systems Inc.Frederick, Maryland USA 21704

Telephone: (301) 620-2033 Facsimile: (301) 620-1396

Checklist for Completed Installation

Frederick, Maryland USA 21704

OHS Series Remote Condensing Unit Telephone: (301) 620-2033Facsimile: (301) 620-1396

❏ 1 Proper clearances for service access havebeen maintained around equipment.

❏ 2 Equipment is level and mounting fasteners aretight.

❏ 3 Piping completed to refrigeration equipment.

❏ 4 All field installed piping leak tested.

❏ 5 Refrigerant charge added.

❏ 6 Incoming line voltage matches equipmentnominal nameplated rating ± tolerances.

❏ 7 Main power wiring connections to theequipment, including earth ground, have beenproperly installed.

❏ 8 Customer supplied main power circuit breaker(HACR type) or fuses have proper ratings forequipment installed.

❏ 9 Control wiring connections completed toremote condensing unit.

❏ 10 All wiring connections are tight.

❏ 11 Foreign materials have been removed frominside and around all equipment installed(shipping materials, construction materials,tools, etc.).

❏ 12 Compressor and fan rotate freely withoutunusual noise.

❏ 13 Inspect all piping connections for leaks duringinitial operation.

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(©December, 2006)


Frederick, Maryland USA 21704

OHS Series Remote Condensing Unit Telephone: (301) 620-2033Facsimile: (301) 620-1396

Periodic General Maintenance Checks and Services ChecklistDate: ____________________________ Prepared By: ___________________________

Model Number: ____________________________ Serial Number: __________________________

Item Number: ____________________________

Monthly

❏ Remote Condensing Unit Clean and Clear of Obstructions

Semi-Annually

❏ Check Refrigerant Charge (bubbles in sight-glass) ❏ Tighten Electrical Connections

❏ Check Suction & Discharge Pressure ❏ Ensure Motor Mount is Secured

❏ Ensure Refrigerant Lines are Secured ❏ Clean Unit as Necessary

Annually

❏ Inspect Refrigerant System for Leaks and Corrosion

❏ Conduct a Complete Check of All Services ListedAbove and Clean Unit's Interior

Notes:____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Signature:________________________________

*** If factory assistance is required for any reason, provide the model number, serial number, and SATS itemnumber found on the unit nameplate. This will speed the process and ensure accuracy of information. ***

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(©December, 2006)


Appendix B- Glossary

Definition of Terms and Acronyms

SATS - Stulz Air Technology Systems, Inc.

BMS - Building Management System

BTU/Hr - British Thermal Units Per Hour

CNDCT - Conductor

ESD - Electrostatic Discharge

º F - Degrees Fahrenheit

FLA - Full Load Amps

FOB - Freight on Board

HACR - Heating, Air Conditioning, Refrigeration

HP - Horse Power

Hz - Hertz

KVA - Kilo Volt Amps

kW - Kilowatt

LRA - Locked Rotor Amps

MAX CKTBKR - Maximum Circuit Breaker

MAX FUSE - Maximum Fuse

MCA - Minimum Circuit Ampacity

MSDS - Material Safety Data Sheet

NEC - National Electric Code

NFPA - National Fire Protection Agency

PH - Phase

PSG - Product Support Group

PSI - Pounds Per Square Inch

PSIG - Pounds Per Square Inch Gauge

RLA - Run Load Amps

R-Value - Thermal Resistance

R-22 - Refrigerant (HCFC-22)

R-407C - Blended Refrigerant

SPDT - Single Pole, Double Throw

TXV - Thermal Expansion Valve

V - Volt

VAC - Volt, Alternating Current

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