"Putting a Damper on Cold Air"

Installation Instructions for HMI HOYME Motorized

COMBUSTION AIR CONTROL DAMPER – VERTICAL MOUNT – 24 Vac

Series HOM Interlocks With Safety Control Systems – Gas, Oil, Boilers & Furnaces

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This motorized Combustion Air Control Damper, Series HOM, fastens to the terminating end of a fresh air inlet duct leading into the heating appliance area and is designed to stop the inflow of cold air when not required. It is interlocked to the appliance safety control system so that the damper proves to be open before the appliance fires and closes when the fire stops. Power (24Vac) is supplied to the Damper from the appliance transformer and/or an auxiliary transformer connected to the appliance power source. The damper with one circuit may be connected to one appliance only (SF1). A Damper with two separate circuits (SF2) may be connected to two separate appliances. Provision is also made to allow the HOYME Replacement/ Ventilation Air Control Damper, Series HAC, to be connected in ‘TANDEM’ to supply VENTILATION air simultaneously  with COMBUSTION AIR.

For COMMERCIAL installations, RELAY ADAPTORS have been designed to interface the  damper to a 250mVdc – 100Vdc, 120Vac Safety Control System. Where the demand for combustion air exceeds the area of one damper, several Dampers in MODULES may be field assembled and interconnected in tandem to one appliance.

Each damper comes with an override manual ‘TEST/RUN SWITCH’.  This switch is to be in the ‘UP’ (run) position for normal operation of the damper. For details on the use of the Test/Run switch, see ‘Troubleshooting Procedure’. 

Air intake duct installation shall be in accordance with: In Canada - can/CSA b149 & b139; In the USA – ANSI/NFPA 54, 2006, ANSI Z223.1 and/or local codes including local codes relating to ventilation air duct installation. A qualified contractor shall be consulted regarding air supply requirements for other appliances and for the building at large and regarding sealing of the building envelope. Notwithstanding the presence of this Damper, provision shall also be made for air supply to the appliance area as per codes cited above. If sizing codes are not available in certain locals, use: 1.0 sq. in. of duct cross-section per 7000 BTUH of total input rating of all appliances in that area.

The DAMPER is designed to be tight sealing, self cleaning with nylon bearings to provide many years of trouble free service. Lubrication is not necessary. Damper and appliance shall be inspected and serviced annually. If Damper fails to close when required, check for ‘UP’ position of the Test/Run switch. Do not obstruct the air intake duct. Have it serviced immediately by qualified service personnel. Type SF2 shall be installed on or nearest the largest appliance and in the proximity of the  second.

 INSTALLER must be a trained, qualified person. Name and address of installer and date of installation shall be recorded on label located on central body. Labels and damper position shall be readily visible when in the installed position.

-Before interconnecting this Damper to a safety control circuit, the heating appliance must be checked for proper operation, according it its manufacturer’s specifications and according to applicable codes.

-When connecting to other than 24Vac, use HOYME Relay Adaptors for 250Vdc – 100Vdc or 120Vac  safety control systems.

-When needed, an approved 24Vac transformer of ample capacity shall be added with the primary leads connected to the line voltage supply of the appliance.

-If existing safety circuit is not fused, (as in older model furnaces) install an in-line fuse between the thermostat wire and the damper black wire #1.

-Always conduct a thorough check-out after installation is complete.

-Sequence the appliance through at least three normal cycles to confirm proper operation.

-Affix appropriate labels and follow instructions and warnings on each label.

 

Mounting Procedure: See Diagrams Below.

Step 1. Screw mounting bracket to the side of the appliance making sure that no damage is done to any functional component of the appliance. Mount bracket in the vertical position aligning the bottom of the bracket within one foot above the burner level of the appliance and within two feet horizontally from the front.

 

Step 2. Mount Damper to the bracket. Mount damper so that air will discharge towards the front of the appliance, if possible, for supply of combustion air.

 

Step 3. Secure expanded metal cage at bottom to the side of the appliance. See Dia. Step 3.

Installation Package For Combustion Air Control Damper, Series HOM

1  -  Reverse mounting bracket

5  - #8 x 9/16” sheet metal screws

1  - Wire nut (Marrette)   (2 for SF2)

3  -  Labels, self sticking (6 for SF2)

1  -  Installation Instructions.

 

SCHEMATIC WIRING DIAGRAM OF DAMPER SERIES HOM INTERCONNECTED TO 24Vac SAFETY CONTROL SYSTEM USING

APPLIANCE TRANSFORMER.

Motor 0.33 Amps. Relay coil 0.05 Amps – does not usually require adjustment of thermostat heat anticipator.

 

Note: This marking is also on label to be affixed adjacent to appliance wiring diagram.

*Inline fuse required if circuit is not previously protected.

- Fuse shall be rated at not more that 200% of the current

 drawn by the circuit.

- Internal connection, factory installed for Type SF2. -- -- --

- Regular circuits    -------------.

- Jumper connection, factory removed for Type SF2. ===

- Damper Field circuits    -- -- -- -- --.

- Typical location for 24Vac Limit Control when used in appliance circuit /_\ .

- Additional wire shall be of the same size and type as originally used.

- Optional switch may be field installed to over-ride Damper.

- Optional series ‘HAC’ Power Close Fresh Air Damper may be connected to terminals 4 and 5. Check transformer capacity.

- Optional Switch and terminals 4 and 5 may be used only in accordance with the Requirements of the Authorities having jurisdiction.

HOOK-UP PROCEDURE

USING APPLIANCE TRANSFORMER–24VAC

Note:  The TEST/RUN Switch on the side of the control body shall be in the ‘UP’ position for normal operation.

Note: Damper is power closed when appliance is not firing, and drops open by gravity when appliance fires or when the TEST/RUN switch  is in the ‘DOWN’ position.  

1. Turn stat to lowest setting.

2. Turn off electrical power supply.

3. Connect Damper BLUE (5) wire, together with stat wire, to R on appliance terminal strip. (TH-TR)  e.g. Transformer 24VAC-Live.

4. Connect Damper BROWN (3) to C (or T) on appliance terminal strip. (TR) e.g. Transformer 24VAC-Common Ground.

5. Test by turning on power supply. Damper will close. Turn off power supply.

6. From W on appliance terminal strip, (TH) remove stat wire and connect to Damper BLACK (1) wire (Sensor). NOTE: * In-line fuse to be connected here if circuit is not previously protected  (Applies to older type appliance).

7. Connect Damper RED (2) wire back to W on appliance terminal strip (TH) (Signal).

8.  Turn stat to call for heat. Damper will open and appliance will operate normally.

 

When using Type SF2, Damper terminals 6, 7 and 8 (White) are to be connected to second appliance respectively and in similar manner as terminals 1, 2 and 3 above.

 

N.B. DO NOT GROUND GREEN WIRE.  CHECK

 

WIRING DIAGRAMS FOR GREEN WIRE USE.

 

Instructions 3 and 5 do not apply when connecting to second appliance. Check label on inside cover of control body for final number and color identification.

 

         -- -- -- -- --     Damper Wires Field Installed

 

SCHEMATIC WIRING DIAGRAM OF DAMPER SERIES HOM INTERCONNECTED TO 24Vac SAFETY CONTROL SYSTEM USING

AUXILIARY TRANSFORMER.

Motor 0.33 Amps. Relay Coil 0.05 Amps-does not usually require adjustment of thermostat heat anticipator.

    Note: This marking is also on label to be affixed adjacent to appliance wiring diagram.

 

*Inline fuse required if circuit is not previously protected.

- Fuse shall be rated at not more than 200% of the current drawn by  the circuit.

- Internal connection, factory installed for Type SF2. -- -- --

- Regular circuits      -----------.

- Jumper connection, factory removed for Type SF2. = = =

- Damper Field circuits   -- -- -- --.

- Additional wire shall be of the same size and type as originally  used.

- Optional switch may be field installed for remote control to over-ride  Damper.

- Optional series ‘HAC’ Power Close Fresh Air Damper may be connected to terminals 4 and 5. Check transformer capacity.

- Optional Switch and terminals 4 and 5 may be used only in Accordance with the Requirements of the Authorities having Jurisdiction.

- Installation of the auxiliary 24Vac transformer leads must  be connected to the line voltage of the appliance.

 - Follow applicable codes.

 

 HOOK-UP PROCEDURE USING

AUXILIARY TRANSFORMER – 24Vac

Note: This installation procedure may be used where appliance transformer is not easily accessible and therefore requires an auxiliary 24VAC transformer to power close the Combustion Air Control Damper. Identification of the ‘TH’ or ‘T’ stat orientation is not necessary. This installation is especially applicable to OIL  or ANY 24 Vac appliance safety control system.

Note: TEST/RUN Switch on the side of the control body shall be in the ‘UP’ position for normal operation. 

NOTE: Refer to Instruction #9 for PROPER PHASING of AUXILIARY Transformer.

1. Turn stat to lowest setting.

2. Turn off electrical power supply and install auxiliary transformer.

3. Remove one stat wire from appliance stat terminal and by using a wire nut, join four wires: Stat wire, Damper BLUE (5) wire, 24Vac auxiliary wire and a stub wire. Connect stub wire back to appliance stat terminal.

4. Connect Damper BROWN (3) wire to remaining 24Vac auxiliary transformer wire.

5. Test by turning on power supply. Damper will close. Turn off power supply.

6. From remaining appliance stat terminal, remove stat wire and connect to Damper BLACK (1) wire with wire nut supplied. (Sensor) NOTE: * In-line fuse to be connected here if circuit is not previously protected.

7. Connect Damper RED (2) wire back to appliance stat terminal. (Signal)

8. Turn on power supply and Damper should close. If Damper does not close, interchange auxiliary transformer wires, turn on power and Damper will close.

9. Check for PROPER PHASE of AUXILIARY TRANSFORMER by momentarily jumping Damper BLACK (1) wire to Damper RED (2) wire. If Damper opens, an out-of-phase trans-former is indicated. Correct by inter changing auxiliary 24Vac transformer wires and retest. 

10. Turn stat to call for heat. Damper will open and heating appliance will operate normally.

 

N.B.:GREEN wire is not to be grounded. Check wiring diagram for use with a Series HAC damper.

Note: When using Type SF2, Damper terminals 6, 7 and 8 (White) are to be connected to second appliance respectively and in similar manner as terminals 1, 2 and 3 above. Instructions 5 and first part of instruction 3 do not apply when connecting to the second appliance.

 

TROUBLESHOOTING ‘HOM’ COMBUSTION AIR CONTROL DAMPERS c/w TEST/RUN SWITCH

 

General: The damper uses power to close when the appliance is not firing and does not use power when the appliance is firing. This prevents overloading the transformer.

 Two wires from the motor are connected to the appliance transformer and two wires from the relay are connected in series with one stat wire.

 Condition: Damper does not close after appliance completes its firing cycle.

Cause: Indicates 1) Test/Run switch is not in the ‘up’ position or 2) a faulty relay or 3) no power supply or 4) faulty motor.

 Procedure: 1) Check Test/Run switch to be in the ‘up’ position. If no response, 2) remove control body cover and use a jumper between terminals 3 & 4. If damper closes – faulty relay. If no response, 3) check power supply to terminals 3 & 5 or 4) connect power supply to terminals 4 & 5. No response indicates a faulty motor. 

 Condition: Damper does not open when stat asks for heat.

 Cause: This indicates 1) signal is not getting through from the stat to the relay or 2) damper is stuck closed or 3) mechanical friction in motor gears.

 Procedure: 1) Check in-line fuse, if used, between stat wire and damper black wire #1. If this is not the cause, remove control body cover and with jumper, join terminals 1 & 5. If damper opens, a faulty stat is suspected. Turn Test/Run switch to the ‘down’ position and if appliance does not fire, a faulty stat is confirmed. 2) If the damper has not been activated for a period of time, (e.g. summer months) the damper might stick closed due to residue. Clean the damper blade with soap and water. 3) Motor gears wear with age causing increased friction which prevents the damper from opening freely. Replace motor.

Condition: Damper opens on stat signal but appliance does not fire.

Cause: This indicates: 1) appliance faulty or 2) improper linkage to the end switch or 3) a faulty end switch.

 Procedure: 1) The combustion Air Damper is interlocked with the heating appliance control system.  This feature is by-passed by using the TEST/RUN switch in the down position. This re-connects the stat wire direct to ‘W’ (TH) on the appliance. If heating appliance does not fire with this switch in the down position, a faulty heating system is suspected. If appliance responds, 2) Check end switch linkage by listening for a ‘click’ as the damper blade opens to approximately 30 degrees. To correct, bend switch lever arm to suit. 3) If linkage is correct, a faulty end switch is suspected.

 

DAMPER CONTROL with TEST/RUN Switch: This feature makes is possible to control the damper in the open position should extra ventilation be desired for a longer period of time. The damper, however, shall  open and remain open while the TEST/RUN switch is in the down position.   

 

*IN-LINE FUSE HOLDER AND FUSE:

Part number #3152-001 includes 3 amp fuse. Not supplied with damper. May be ordered direct from the factory.

For more information, please contact

HMI HOYME Manufacturing Inc.

@ 1-800-661-7382, or www.hoyme.com

 

 

 

 

 

 

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