Installation instructions – Printer friendly (pdf)
ADP-0242-05A – Information Page
Installation Instructions for HMI HOYME Adaptor ADP-0242- 05A
24Vac Controlled Voltage – Switches 24Vac / 120Vac
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- 4” x 5” x 2 1/2” (101 x 127 x 64 mm)
- This Adaptor has two 24Vac Relays. The contact points of one relay can be used to control a 120Vac circuit of up to 5 amp draw such as running a 120Vac exhaust fan. These instructions, however, involve 100% 24Vac switching
- The 24Vac relay points or manual contact points from the switch of an Exhaust Fan will simultaneously turn on the Exhaust Fan, the furnace circulating fan, and open a fresh air inlet damper. The open damper will assist the flow of fresh air into the system while the exhaust fan is on. This adaptor, having a second relay, also allows the thermostat to open the damper during the heating cycle of the furnace (See wire diagrams below)
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Installation of this Damper shall be in accordance with the requirements of the authorities having jurisdiction
Refer also to HMI HOYME Installation Instructions for:
- Series HOM Combustion Air Control Damper
- Series HAC Replacement/Ventilation Air Control Damper
- Adaptor ADP- 0241- 05A
Suggestion: If controlled line voltage is available from the exhaust fan switch to the Adaptor area, use Adaptor ADP-1102-TWP and follow its installation instructions
Fitness of this Adaptor/Damper combination to satisfy air supply requirements for fuel fired appliances during operation of the Inter-connected exhaust fan(s) shall be investigated by the enforcing authorities
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
Product ID
- One Relay, 24Vac. Coil-0.05A, 120Vac DPDT Points 5 Amps
- One Relay, 24Vac. Coil-0.05A, 120Vac SPDT Points 5 Amps
- Adaptor line voltage leads, connected to the appliance shall be suitably cabled, fastened and enclosed in suitable raceways
- Refer to local and applicable codes
- If an Auxiliary Transformer is required, use an approved 24Vac Transformer of adequate capacity
- Supply for the transformer primary shall be taken from the line voltage supply of the appliance. Refer to applicable codes
- Always conduct a thorough check-out after installation is complete
- Affix appropriate labels and follow instructions and warnings on each label
Installation Instructions
- Install Motorized Air Control Damper as per instructions supplied with it. Satisfactory operation of the damper is recommended before interconnecting Adaptor
- Turn off electrical power supply to each appliance
- Connect Adaptor line voltage leads (used here for 24Vac circuit only) as per wiring diagram
- Connect appropriate Adaptor terminals to the proper PO/PC damper, to the proper heating appliance terminals and to the auxiliary fan control switch.(See damper wiring diagram for proper circuit)
- Turn on electrical power to 24Vac appliance transformer. If damper is a Power Open type, it will remain closed at this time. If damper is a Power Close type, it will close at this time
- Turn on selected switches at least 3 times to verify the intended operation of selected circuits
Schematic Wiring Diagram for – ADP- 0242- 05A
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Note: This marking is also on the cover of the Adaptor unit as well as on a label to be placed next to the wiring diagram of the appliance
Schematic Wiring Diagram – ADP-0242-05A
Activated by an Exhaust Fan Auxiliary Relay Switch 24Vac or manual switch to simultaneously turn on an exhaust fan, a furnace circulating fan and open a Fresh Air damper. The second Relay actuates the fresh air damper during the heating cycle of the furnace
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Suggestion: Use Fresh Air Damper – HAC-0X10-OPO/PC
- X = Diameter of damper
- PO= Power Open
- PC=Power Close.
For more information, please contact HMI HOYME Manufacturing Inc. @ 1-800-661-7382
Installation instructions – Printer friendly (pdf)
ADP-0242-05A – Information Page