Diagnostics
CNT-SVX06B-EN 63
High/Low Pressure Cutout
Circuits 1 and 2
Abnormal refrigerant pres-
sures
Fan off
Compressor 1 off
Compressor 2 off
Damper closed
Smart reset/
Manual
Zone Temp Failure Invalid or missing value for
zone temperature
Fan off
2
Valves closed
Electric heat off
Compressors off
Damper closed
Automatic
Leaving Water Temp Failure Invalid or missing value for
zone temperature
Fan unaffected
2
Compressor 1 off
Compressor 2
2
Damper
2
Manual
Discharge Air Temp Failure Invalid or missing value for
zone temperature
Fan unaffected
Valves unaffected
Electric heat unaffected
Compressors unaffected
Damper unaffected
Automatic
Setpoint Failure Invalid or missing value for
zone set point
Fan unaffected
Valves unaffected
Electric heat unaffected
Compressors unaffected
Dampers unaffected
Automatic
Fan Mode Failure Invalid or missing value for
fan mode switch resistance
Fan unaffected
Valves unaffected
Electric heat unaffected
Compressors unaffected
Damper unaffected
Automatic
Invalid Unit Configuration Software configuration is
done improperly
Fan off
Valves closed
Electric heat off
Compressors off
Damper closed
Manual
Normal—Power Up On start-up Fan unaffected
Valves unaffected
Electric heat unaffected
Compressors unaffected
Damper unaffected
Automatic
Table 18. Diagnostics for heat pump configurations (Continued)
Diagnostic Probable cause Consequences
Diagnostic
type
1
1 For more information on types of diagnostics and how they are cleared from the controller, see “Clearing diagnostics”
on page 66.
2 High/low pressure cutout and low temperature detection diagnostics for water-source heat pump configurations isolate
each circuit and independently disable compressor operation. For single compressor units, these diagnostics cause the
compressor to shut down, the unit fan to be controlled off, and the outdoor air damper to be closed (when present).