Bryant P/N TSTATBBP220-LA instruction manual Thermostat Troubleshooting, Problem Solution

TROUBLESHOOTING

Table 4 Ð Thermostat Troubleshooting

PROBLEM	SOLUTION
Display on thermostat not illuminated.	Check for 24 vac at the R terminal connection. Terminal R must
	be connected for proper thermostat operation.
``Service Filter'' is displayed on thermostat.	After the con®gured number of blower operating hours, the Service
	Filter message will be displayed. This reminds the owner to re-
	place the ®lter. Reset the Service Filter feature to reset the blower
	operation timer to 0 hours.
Cooling will not energize.	Select COOL mode. Decrease cooling set point to 10 degrees
	below room temperature. Check for 24 vac at Y1 terminal. If present,
	thermostat is operating correctly and problem is with wiring or equip-
	ment. If 24 vac is not present, replace the thermostat. Check for
	Compressor Cycle per Hour Limit. Cooling may be locked out.
Heating will not energize.	Select HEAT mode. Increase heating set point to 10 degrees above
	room temperature. Check for 24 vac at W1/O/B terminal. If present,
	thermostat is operating correctly and problem is with wiring or equip-
	ment. If 24 vac is not present, replace the thermostat.
When using 4 wires (R,G,W,Y), the cooling equip-	There is not enough power available. Connect a 270 ohm, 10 watt
ment tries repeatedly to turn on, but cannot. At	power resistor at the air-conditioning equipment between terminals
times the display dims or disappears.	W and C (non-heat pump applications only).
When using 4 wires (R,G,W,Y), the heating equip-	There is not enough power available. Connect a 270 ohm, 10 watt
ment tries repeatedly to turn on, but cannot. At	power resistor at the air-conditioning equipment between terminals
times the display dims or disappears.	Y and C (non-heat pump applications only).
When controlling a heat pump, heat comes on	Con®gure thermostat for heat pump operation (Table 2, Step 3).
during cooling cycle.
When calling for cooling, both heating and cool-	The thermostat is con®gured for a heat pump. Con®gure the
ing are energized.	thermostat for non-heat pump operation (Table 2, Step 3).
When controlling a commercial heat pump unit,	Commercial heat pumps require that Heat Pump Option on
unit runs in reverse or heating is always on.	thermostat is turned OFF.

Copyright 1998 Bryant Heating & Cooling Systems CATALOG NO. 809-683