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OPERATION&MAINTENANCEMANUAL
HVACSYSTEM(AIRSIDE)VRVAIRCONDITIONINGSYSTEM
6. MAINTENANCE
I M P O R T A N T : The material contained in this Section is designed as a general overview ofmaintenance requirements and may not contain answers for specific maintenance questions.
Consult the manufacturers instruction manuals, in BOOK-4 section 13 of this O&M forspecific maintenance information.
6.1 GENERAL
6.1.1 Maintenance Precautions
Personal Protective Equipment (PPE) Required!
Installing/servicing this unit could result in exposure to electrical, mechanical and chemicalhazards.
Before installing/servicing this unit, technicians MUST put on all Personal ProtectiveEquipment (PPE) recommended for the work being undertaken. ALWAYS refer to
appropriate MSDS and OSHA guidelines for proper PPE.
When working with or around hazardous chemicals, ALWAYS refer to appropriate MSDS and
OSHA guidelines for information on allowable personal exposure levels, proper respiratoryprotection and handling recommendations.
If there is a risk of arc or flash, technicians MUST put on all Personal Protective Equipment(PPE) in accordance with NFPA70E or other country-specific requirements for arc/flashprotection PRIOR to servicing the unit.
Failure to follow recommendations could result in death or serious injury.
WARNING Hazardous Voltage!
Disconnect all electric power, including remote disconnects before servicing. Follow
proper lockout/tagout procedures to ensure the power can not be inadvertently
energized. Failure to disconnect power before servicing could result in death or
serious injury.
WARNING Contains Refrigerant!AVOID prolonged breathing of the vapor. Prolonged inhalation of refrigerant is
extremely dangerous; death can occur without warning
CAUTION
ALWAYS wear protective goggles when working with refrigerant. If liquid
refrigerant gets in your eye, permanent blindness may result
DO NOT allow refrigerant to come in contact with your skin. Refrigerant has a
very low boiling point, which will cause frostbite
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OPERATION&MAINTENANCEMANUAL
HVACSYSTEM(AIRSIDE)VRVAIRCONDITIONINGSYSTEM
6.1.2 Maintenance Planning
Since maintenance work is generally done in the least time possible, maintenance activitiesshould be planned. In addition to ensuring that the necessary materials, tools, parts are
assembled and prepared for use in advance of the work, the maintenance activity plan
should also cover all aspects of the activity which may include the following.
Scheduling with operations
1. Site access
2. Calibrated test equipment for each test required
3. Necessary lighting, electrical power, and service air to perform the work
4.
Cleaning aids consisting of clean, white, lint-free cloths; solvents; vacuum cleaner;
and dry compressed air
5. Personnel safety equipment required for the specific maintenance activities beingperformed
6.1.3 Maintenance program
A total maintenance program for Hangar facility must contain elements of both preventiveand predictive maintenance. Preventive maintenance is the systematic care and servicing of
equipment and facilities to prolong their useful life. Predictive maintenance consists of theperformance of periodic equipment inspections to identify and monitor symptoms (such as
increasing wear, abnormal vibrations, or increasing power usage) which indicate that
mechanical failure of a piece of equipment may be approaching. The goal of predictivemaintenance is to develop an awareness of developing problems so that needed repairs can
be made on a planned rather than on an emergency basis and unscheduled system downtime resulting from unpredicted equipment failure is avoided. Effective execution of a total
site maintenance program requires the implementation of the following elements.
1. Training and instruction of maintenance personnel, operators, and users of the
particular equipment systems in proper operation, maintenance, and safetyprocedures.
2. Systematic, periodic inspection and servicing of plant systems and equipment by
skilled maintenance personnel.
3. Assignment of specific maintenance responsibilities to skilled maintenance personnel
and to operators of equipment.4. Continuing supervision of the site maintenance program.
5. Periodic utility systems maintenance inspections to ensure the maintenance program
is being implemented.
Only a regular and organized scheme of maintenance work, planed, to cover all details ofthe installation within given maintenance periods, can ensure continued satisfactory
operation with a minimum liability to interruption to supply due to equipment faults. Aplanned maintenance scheme should include a system of logging, wherein records are kept
on inspection, maintenance and repair of all items of plant and equipment.
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OPERATION&MAINTENANCEMANUAL
HVACSYSTEM(AIRSIDE)VRVAIRCONDITIONINGSYSTEM
Careful attention must be given to securing the safety of personnel and equipment whilemaintenance or repair is in progress. A code of safety rules based on system permit to
work is recommended.
Where maintenance work in progress is in progress, a DANGER notice must always be
attached to any Live apparatus calling attention to the danger of approach, A CAUTIONnotice must always be attached to plant or its associated control equipment which may
occasioned by interference. Before any work is commenced on any items of equipment, thesupply and ancillary circuits must be isolated and locked off if possible.
Warnings!
In the event of a refrigerant leak, thoroughly ventilate the room. If refrigerant leaks and
comes in contact with an open flame, toxic gases will be generated.
After installation & maintenance work has been completed, check for refrigerant leaks.
Caution:
Do not touch the refrigerant pipes with bare hands during operation. The refrigerant
pipes are hot or cold depending on the condition of the flowing refrigerant. If you touchthe pipes, burns or frostbite may result.
After stopping operation, be sure to wait at least five minutes before turning off the
main power switch. Otherwise, water leakage or breakdown may result.
Do not use refrigerant other than R410A refrigerant. If another refrigerant is used, the
chlorine will cause the oil to deteriorate.
Use the following tools specifically designed for use with R410A refrigerant.
Gauge manifold
Flare tool
Charge hose
Size adjustment gauge
Gas leak detector
Vacuum pump adapter
Torque wrench
Electronic refrigerant charging scale
Be sure to use the correct tools. If dust, debris, or moisture enters the refrigerant lines,
refrigeration oil deterioration may result.
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OPERATION&MAINTENANCEMANUAL
HVACSYSTEM(AIRSIDE)VRVAIRCONDITIONINGSYSTEM
6.2 GENERAL MAINTENANCE
Inspection Action Frequency
Hangars and
Support
Inspect hangers and supports:
Check for corrosion, wear, and failed parts.
Make certain that all supports are in line withthe piping and tracking true,
Make certain that each hanger is carrying itsshare of the load; and that there are no signs
of imminent failure of any stressed member.
Yearly
Check the refrigerant piping for leaks and propersupport. Repair defective connections. 3 monthly
Check piping insulation to make sure the insulation
is still wrapped around piping. Repair or replace ifneeded.
3 monthly
Check piping for dents and frosting. Replace piping
section if dents are found.3 monthly
RefrigerantPiping
Check piping for unnecessary vibration, noise, and
wear. Repair and eliminate vibration and wear.3 monthly
Inspect outer surface for damage. Repair orreplace as necessary
Yearly
Insulation
Check integrity of vapors seals Yearly
Indoor Unit
Remove and clean air filter Monthly
Clean surfaces of casing 3 monthly
Brush or vacuum clean evaporator coil surfaces 3 monthly
Check for correct operation of control 3 monthly
Check fan is free to rotate 3 monthly
Check for unusual noise of vibration 3 monthly
Clean out drip tray and ensure condensate drain isfree from obstruction
3 monthly
Check unit for sign of leakage 3 monthly
Indoor UnitGeneral
Inspection
Check and maintain component items refer to
individual components maintenance scheduleVarious
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OPERATION&MAINTENANCEMANUAL
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General Maintenance Continued
Inspection Action Frequency
Outdoor Unit
Inspect units for signs of leakage or corrosion
Clean of any deposits and treat any bare metal
accordingly
3 monthly
Clean condenser coil surfaces 3 monthly
Check fans are free to rotate and impellers aresecure onto shaft
3 monthly
Check operation of control 3 monthly
Check refrigerant charge 3 monthly
Check operation of crank case heater 3 monthly
Check crankcase oil level, top up as required 3 monthly
Check for unusual noise or vibration 3 monthly
Outdoor UnitGeneral
Inspection
Check and maintain component items refer toindividual components maintenance schedule
Various
6.3 COMPRESSOR
Inspection Action Frequency
Check compressor for sign of leakage Weekly
Check oil level Weekly
Check oil is contaminated with refrigerant Weekly
Check for unusual noise or vibration Weekly
Inspect compressor for sign of corrosion Yearly
Check security of electrical connection Yearly
Compressor
Check and maintain component item (Electric
Motor) refer to individual componentmaintenance schedule.
Various
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OPERATION&MAINTENANCEMANUAL
HVACSYSTEM(AIRSIDE)VRVAIRCONDITIONINGSYSTEM
6.4 FILTER
Caution:
Do not dry the filters in direct sunlight or by using a heat source, such as an electric
heater: this may warp them.
Do not wash the filters in hot water (above 50C), as this may warp them.
Make sure that the air filters are always installed. Operating the unit without air filters
can cause malfunction.
Caution:
In removing the filter, precautions must be taken to protect eyes from dust. When the filter is removed, do not touch the metallic parts inside the indoor unit,
otherwise injury may result.
Inspection Action Frequency
Take the manometer reading, If the reading shows
the filter cells are at their maximum pressuredrops, they should be washed. After washing
check the condition of filter medium, if damagedreplace.
MonthlyFilter
Wipe any accumulated dirt from the retaining
channels and frames
Monthly
Note : On replacing access doors check that the integral seals give a good air seal, if
not, replace seals
Please refer to manufacturer literature on sections 13.4, 13.5, 13.6, 13.7 of this
manual for filter removal & cleaning proof particular models
6.5 COOLING COIL
Inspection Action Frequency
Check pipe work connection for leak 3 Monthly
Check coil matrix is clean, unobstructed and airflow is evenly distributed over coils
3 Monthly
Check condensate drain pans and connection areclear. Check drain pipe is properly attached
3 MonthlyCooling Coil
Clean Coil Matrix, Use soft brush and mild
detergent solution, If heavily contaminated withgrease use steam lance, Take care not to damage
or distort fins
6 monthly
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HVACSYSTEM(AIRSIDE)VRVAIRCONDITIONINGSYSTEM
6.6 FAN
Inspection Action Frequency
Check fan is running smoothly without excessive
noise or vibrationDaily
Check flexible connection are secure and airtight Weekly
Check that fan guards is clean and unobstructed Weekly
Check anti-vibration mountings / hangars are
secure, free to move and in good conditionMonthly
Check impeller and shaft for freedom of movementand balance 6 monthly
Clean and check casing internally and externally,
repair any corrosion or damage to finish found.
Check all bolted joints are secure
Yearly
Fan
Check and maintain component items (electricmotor) refer to individual components
maintenance schedule
Various
6.7 ELECTRIC MOTOR
Important:Always ensure that electrical supply to the motor is positively isolated
before carrying out any operation
Inspection Action Frequency
Generally check motor to ensure casing ventilation
louvers are unobstructed, alignment is correct,holding down bolts and pulley/couplings are
secure, and motor without excessive vibration,
temperature and noise.
Monthly
Totally enclosed motors only-Check that casingdrain holes are unobstructed or if plugged, remove
plugs to drain off any accumulated condensation.
Monthly
Check motor terminals are secure, cables show nosigns of overheating, terminal box is internally dryand clean, and cover is refitted securely
6 monthly
Check that insulation resistance across winding isat an acceptable value
6 monthly
Check centrifugal switch for wear and action 6 monthly
Check drawn full load current does not exceed
value stated on the name plate6 monthly
Electric Motor
Dismantle and overhaul motor in accordance with
manufacturer recommendations3 yearly
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