Timer, 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 #9: Forced Air Furnace having a combustion air supply duct and a replacement air supply duct together with an exhaust fan controlled by a designated ventilation switch and/or an optional bathroom timer and an interval timer.
3. Ventilation Switch and/or an optional bathroom timer to supply Controlled and a Regular 3-Wire 120Vac power supply to the furnace area.
4. Relay Adaptor with Interval Timer (TMADP-1102-TPX) to function as a control centre.
1. Combustion Air Damper and Replacement air damper open during furnace firing.
2. Ventilation Switch and/or bathroom timer turns on Ventilation Fan, opens Replacement Air Damper and turns on Furnace Fan simultaneously.
3. Interval Timer can be set for minimum or multiple consecutive settings of 15 minutes to turn on the Ventilation Fan open the Replacement Air Damper and turn on the Furnace Fan simultaneously.
4. Optional Switch allows full control of a PC Replacement Air Damper.
N.B. Replacement Air Damper is not affected by the ‘Manual’ setting of the furnace fan.
1222-ld - Printed in Canada
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