Timer, Vent Switch, Replacement Air, Power Open, and an Exhaust Fan with 3-way Ventilation Switch:
#9C1. Same as #9B1 But has a Designated Ventilation Switch which functions fully and also an additional 3-Way Switch to control Ventilation Fan only.
HMI Hoyme Manufacturing Inc. Special Note: Circuits are colored for clarification only and are not necessarily those found in actual installations. Combustion Air Damper Wires, however, are colored as shown.
Diagram #9C1: Forced Air Furnace having a Replacement Air Supply Duct and an Exhaust Fan controlled by a designated Ventilation Switch, a 3-way Ventilation Switch and an Interval Timer Adaptor.
- Replacement Air Damper, Power Open, (HAC-0x10-OPO)
- Ventilation Switch supplies a Controlled and a Regular 120Vac (3-Wire) power supply to the Furnace area
- A 3-way Ventilation Switch to control Ventilation Fan only
- An Interval Timer Adaptor (TMADP-1102-TPX) which functions as a complete control center
OPERATION:
- Furnace fires with Thermostat signal
- Ventilation switch turns on Ventilation Fan, opens Replacement Air Damper and turns on Furnace Fan simultaneously
- Three-way Ventilation Switch turns on the Ventilation Fan only. (Not recommended unless living in coastal climates warmer than -10ºC and/or ample replacement air is supplied)
- Optional switch (i.e. toggle switch, timer, de-humidistat) connected between #1 and #2 of the Adaptor allows full control of the PO Replacement Air Damper to open as required
N.B. Replacement Air Damper is not affected by the ‘Manual’ setting of the Furnace Fan.