Lower control board for all Deluxe Blend Air II systems. Found inside control box on front of furnace. Wires sold separately.
Replaces 7681-3091/A, 7681-3091, 7681-309, 7681-317 & 7681-317P.
Technician's Tip: The complete Coleman Blend Air system is now obsolete but parts are still available for repair. The system uses an upper board (7681-318P/A) and lower board (7681-317P/A) connected by a harness (7681-327P). The purpose of the Blend Air system is to ventilate the attic and bring fresh air to the furnace. If your system is not working properly, the lower board will beep. Below are some troubleshooting pointers about your Blend Air II system.
1. The motor on the roof runs 4 hours on and 4 hours off. For the motor to shut off, the upper board on the roof must receive a signal from the lower board. If the motor never shuts off, either the cable between the two boards is defective, the cable ends are corroded, or the lower board is defective.
2. If the motor on the roof (1468-2199) fails to run when a signal is being sent by the lower board (causing the board to alarm), the issue is either a bad motor, a bad upper board or the upper assembly is not receiving 120V power.
3. When the furnace calls for heat or air, the lower board opens a damper (7681-5091/A) at the top of the furnace to let fresh air in. If the damper does not open, check for 24V to the damper. If the voltage is low, replace the lower board. If voltage is 24V or higher, replace the damper motor (7681-3231.)