Comfort

F-38

DHUL Listed FintubularAir Duct Heater

• Up to 533 kW

• Up to 35 kW/Ft2 Power Densities

• Up to 600 Volt

• 6 x 8" to 40 x 120" Duct Sizes

Type DH duct heaters are pre-engineered,factory assembled units consisting of astandard frame section, metal sheath heatingelements and a prewired terminal box. Theyare available in a wide range of standard framesizes, with various heating capacities andheating stages operating on AC voltage ratingsof 120 to 600V.

The standard duct heater is designed to beinserted in a rectangular opening cut in theside of a horizontal or vertical duct. For largerducts or where it may be more desirable toattach the duct directly to the heater, a framemay be added to the heater.

Applications

• Primary or Secondary Heating

• Reheating or Preheating

• Comfort Heating in Industrial Buildings,Schools, Hospitals, Department Stores,Warehouses and Office Complexes

• Comfort Heating on Shipboard

Construction

Heavy Gauge Frame of aluminized, painted orstainless steel.

Terminal Box E1 General Purpose or DripProof.

Fintube® Elements — Famous, fast heatresponding, individually replaceable Fintubularelements provide a long life dependable heatsource. Heavy mass of elements reduces cycletime and thermal stress. Aluminum painted,MONEL® or Stainless Steel sheath and finmaterials are available.

Integral or Remote Control panel of identicalheight as duct to ease field installation.

DHRI — Insert Type RemoteControls

DHII — Insert Type IntegralControls

DHRF — Flange Type RemoteControls

DHIF — Flange Type IntegralControls

Insert Type — Dimensions (Inches) Flange Type — Dimensions (Inches)

Features

Insert Heaters — Type DHRI and DHII haveframe dimensions sized so that the entireframe slides through a rectangular opening inthe side of the duct.

Flange Heaters — Type DHRF and DHIF haveface dimensions that exactly match inside ductdimensions. Heater flanges attach to matchingexternal duct flanges in the field.

Pressure Drop — Lower than tubular ductheaters since fewer, higher watt densityelements are required.

For Horizontal or Vertical upflow applications.

Uniform Heat Transfer to airstream sincesheath and fins eliminate localized overheatingon elements.

Listed for zero clearance to combustiblematerials.

Overtemperature Protection provided withboth manual and automatic resets.

Factory Prewired 48 Amp maximum circuitsto meet NEC requirements.

Control Options — The fan circuit must beinterlocked with the control circuit of theheater. The options are air flow switch, faninterlock relay or fan interlock relay with fandelay. Optional disconnecting means includethe choice of non-fused disconnect, fuseddisconnect or terminal block for remotedisconnect by others.

Easy Wiring access through conduit openingin terminal box.

W

H

W

H

2 Typ.

Comfort

FORC

ED A

IR

F-39

Model UL Listed Fintube® Air Duct Heaters

DHRI Duct heater, remote controls, insert type DHII Duct heater, integral controls, insert typeDHRF Duct heater, remote controls, flange type DHIF Duct heater, integral controls, flange type

Code Terminal Box Construction & Terminal Box and Frame Material

GPA General purpose terminal enclosure and all aluminized steel construction DPA Drip proof terminal enclosure and aluminized steel constructionGPP General purpose terminal enclosure and all painted steel construction DPP Drip proof terminal enclosure and painted steel constructionGPS General purpose terminal enclosure and all Stainless Steel construction DPS Drip proof terminal enclosure and Stainless Steel construction

Code Height of Duct (In.)

00H 06 - 40

Code Width of Duct (In.)

000W 08 - 120

Code Depth of Heater Frame (In.)

00.00 06.5 min. - 36.00 max.

Code Heater Voltage

000V Up to 600V

Code Number of Circuits

0

Code Phase

1P Single3P Three

Code kW/Ft2 (max.)

000.0kW 35 kW/Ft2 max.

Code Mounting Position of Heater

1MP Mounting position 1 4MP Mounting position 42MP Mounting position 2 5MP Mounting position 53MP Mounting position 3 6MP Mounting position 6

Code Sheath, Fin and Finish of Heating Element

PS Painted steel fin and sheath (Std.) MO MONEL® fin and sheathSS Stainless Steel fin and sheath

Code Method of Attaching Heating Element to Heater Frame

WA Mounting washer staked to element sheath (Std.)GW Mounting washer staked to element sheath with gasketBF Brass fitting with gasketSS Stainless Steel fitting with gasket

Code Heating Element Termination

M Threaded terminals with mica insulationR Threaded terminals with ceramic insulation (480V max.)H Hermetic seals (480V max.)

Code Fan Interlock Method

AS Air flow switchFI Fan interlock relayFD Fan interlock relay with fan delay

Code Control Circuit Power Supply

T Control circuit by integral transformer(24 or 120V sec. only)

R Remote control circuit by customer(24, 120, 208, 240 or 277V)

Code Control Circuit Voltage

000 24, 120, 208, 240 or 277V

Code Disconnecting Means

ND Nonfused disconnect switch(200A max.)

FD Fused disconnect switch(48A max.)

TB Terminal block (200A max.),disconnect switch by others

DHRI - GPA - 10H X 020W X 06.50D - 480V03P 010.0kW - 1MP - PSWAM - AST120ND Typical Model Number

OrderingInformation

To Order —Complete theModel Numberusing the Matrixprovided.

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DHUL Listed Fintubular Air Duct Heater (cont’d.)

Comfort

F-40

DHUL Listed FintubularAir Duct Heater (cont’d.)Fan Interlock Selection — UL Standard 1096requires an acceptable means of interlockingthe heater with the fan as an integral part ofthe heater, factory installed. One of thefollowing must be used.

Differential Switch — The pressure switchmethod of proving air flow is the most reliable.Minimum requirements are met when thepressure in the sensing tube, combinedvelocity and static, is greater than the switchsetting.

Fan Interlock Relay — A normally open relay(contactor) is wired in series with the ductheater control circuit. The coil of this relay iswired to a terminal block for field connectionto the fan motor starter circuit.

Fan Interlock Relay with Fan Delay Control— Delays the fan or blower motor until afterthe Fintubes have reached a selected tempera-ture, eliminating the initial delivery ofunwarmed air.

Horizontal Duct — Side terminal boxentry for type DHRI & DHRF heaters. Airflow as shown. Install with this arrow up.

Mounting Position 1

Horizontal Duct — Side terminal boxentry for type DHRI & DHRF heaters. Airflow as shown. Install with this arrow up.

Mounting Position 2

Vertical Duct — Side terminal boxentry for type DHRI & DHRF heaters. Airflow as shown. Install with this arrow up.

Mounting Position 3

Horizontal Duct — Side terminal boxentry for type DHII & DHIF heaters. Airflow as shown. Install with this arrow up.

Mounting Position 4

Horizontal Duct — Side terminal boxentry for type DHII & DHIF heaters. Airflow as shown. Install with this arrow up.

Mounting Position 5

Vertical Duct — Side terminal boxentry for type DHII & DHIF heaters. Airflow as shown. Install with this arrow up.

Mounting Position 6

Normally, the number of stages availabledepends upon the number of Fintubes perheater. The number of Fintubes per heater isdetermined by the H dimension of the heater.

Control Circuit Supply — Optional. Built-infactory wired control transformers arefrequently required if a field source of controlvoltage is unavailable for meeting controlcircuit requirements.

A complete selection of transformers withprimary voltages of 120, 208, 240, 277, 380,480 and 600V are available. Secondaryvoltages of 24 and 120 Vac are available.Unless specified, the transformer primaryvoltage will be the same as the heater linevoltage.

Power Disconnect Switch — Optional. Tomeet the UL and NEC requirement for adisconnect switch at or in sight of the heater,its controls and fuses; a built-in disconnect isavailable for power loads greater than 200Amps. When this option is not selected, powerterminal blocks will be provided (200 Ampsmax per block).

Standard No. Fintube®

Elements SuppliedDuct Depth (In.)

Duct Height(In.) 6.5" 12" 17-1/2"

6 2 3 - 4 5 - 68 3 4 - 6 7 - 910 3 - 4 5 - 8 9 - 1212 6 7 - 12 13 - 1814 6 - 7 8 - 14 15 - 2116 6 - 8 9 - 16 17 - 2418 9 10 - 18 19 - 2720 9 - 10 11 - 20 21 - 3022 9 - 11 12 - 22 23 - 3324 12 13 - 24 25 - 3626 12 - 14 15 - 28 29 - 4228 15 16 - 30 31 - 4530 15 - 16 17 - 32 33 - 4832 15 - 17 18 - 34 35 - 5134 15 - 17 18 - 34 35 - 5136 18 19 - 36 37 - 5438 18 - 19 20 - 38 39 - 5740 18 - 20 21 - 40 41 - 60

Heating Control Stages — In order to achievemodulating control of the heater, it is possibleto specify multiple heating steps or stages.