Aprilaire Model 8570 Troubleshooting Cooling Operation, Thermostat does not call for cooling

7. CHECK COOLING OPERATION

Notes:

1.To avoid the minimum off times during system checkout, always start the check out procedure in the OFF mode.

2.Do not operate air conditioning at low outdoor temperatures. Refer to equipment manufacturer’s recommendations for safe operating temperatures.

• Set the thermostat to the OFF mode.

TROUBLESHOOTING – COOLING OPERATION

•Set the thermostat to the COOL mode:

–The O terminal will energize when in the Cool mode.

•Lower the cool setting to 5° below the room temperature to initiate a 1st stage cool call. The mode display will change from “COOL MODE” to “COOLING”, which will flash when the thermostat is calling for cooling:

–Y1 and G terminals will energize.

•Wait 4-minutes for 2nd Stage:

–Y1, Y2 and G terminals will energize.

•Set the thermostat to the OFF mode.

Symptom	Cause
Thermostat does not call for cooling	Minimum-off times. Change the mode to OFF first, then change the mode
	to COOL and make a call for cooling.
Cooling does not come on at all	RC terminal not connected – see wiring diagrams.
	Cooling equipment power not on.
Heat comes on instead of cooling	Reversing valve wiring.
	Miswiring – check wire colors at thermostat and HVAC equipment.

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