ACONT900AC43UA
Pub. No. 11-HD04D1-2
69-2080—05
22
Fan runs all of the time.
1. Fan mode is set to ON -
continuous.
2. Fan scheduled to run
continuously.
3. Indoor equipment may need
service.
1. Set fan mode to AUTO or CIRC.
2. Reprogram fan schedule, if desired.
3. Check Indoor equipment.
Fan is set to “On” but not running. 1. American Standard Heating &
Air Conditioning Proprietary
Humidity Control.
Verify that the Dehumidification setpoint
is below the actual indoor humidity. See
“American Standard Heating & Air
Conditioning Proprietary Humidity
Control” on page 19 for additional
information.
Cooling cycles too fast or too slow
(narrow or wide temperature
swing).
The location of the control and/or
the size of the cooling system
may be influencing the cycle rate.
Verify/adjust cycle rates - ISU 0220,
0230.
Heating cycle too fast or too slow
(narrow or wide temperature
swing).
The location of the control and/or
the size of the heating system
may be influencing the cycle rate.
Verify/adjust cycle rates - ISU 0240,
0250, 0260.
Only Furnace heat; no heat pump
heating in Dual Fuel mode.
1. Outdoor temperature sensor is
missing or no longer reporting.
2. Outdoor temperature is below
the Compressor Lockout
Temperature setting.
1. Check/ repair outdoor sensor field
wiring.
2. Lower the Compressor Lockout
Temperature setting, if desired.
Cannot change system mode to
Heat or Cool mode.
1. Comfort Control not configured
properly.
1. Check/verify System Selection - ISU
0172.
No equipment is running and can
not change the mode from “OFF”.
Equipment was not connected
during Auto-Discovery mode.
1. Check/verify wiring connection and
cycle power to components.
2. Cycle Power - System will Re-initiate
Auto-Discover.
Table 7. Troubleshooting Information
Symptom
Possible Cause
Action
