120Vac vent switch, combustion air, and replacement air 

HMI Hoyme Manufacturing Inc. Special Note: Circuits are colored for clarification only and are not necessarily those found in actual installations. Wires of the Combustion Air Damper, however, are colored as shown. 



Diagram #5: Forced Air Furnace having a combustion air and a replacement air supply duct together with an exhaust fan controlled by a designated ventilation switch.
 
ADDED: 1. Combustion Air Damper (HOM-0x11-SF1)   2. Replacement Air Damper (HAC-0x10-OPC) 3.Ventilation Switch to supply 120Vac to furnace area. 4. Relay Adaptor (ADP-1101-05A) to function as a control centre.
 
OPERATION: 1. Combustion Air Damper and Replacement Air Damper open during furnace firing.  2. Ventilation Switch turns on Exhaust Fan, opens Replacement Air Damper and turns on Furnace Fan simultaneously without interfering with the Air Conditioner. 3. Optional switch (i.e. toggle switch, timer, de-humidistat) provides full control of Replacement Air damper to open separately provided the damper is the Power Close  (PC) type.
 
0828                                                                                                     Printed in Canada

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