The A31/A32 alarm only applies to DC powered supply fans. If this alarm is displayed when the power supply for the fan is AC, change the fan setting SF1 in D menu from 0 to 1 or from AUT/DC to AC. If using the PGD, change option Ch1 in the Manufacturer Menu to AC. See the unit nameplate to determine supply fan power input.
An open signal between terminals 2 and 12 will trigger this alarm.
Single Phase AC Loss Troubleshooting
| Possible Cause | Component to Check | Recommended Action |
| AC Loss | AC Breaker on units | Turn on breaker and make sure prime power is present to the unit |
| Power loss relay failure | Power relay (KA1) | If relay does not close when power is applied to the coil, replace the relay. |
| Loose/incorrect alarm wire | Alarm wiring | Verify/tighten alarm wiring according to the Single Phase AC Loss Wiring diagram. |
Single Phase AC Loss Wiring
Three Phase AC Loss Troubleshooting
| Possible Cause | Component to Check | Recommended Action |
| AC Loss | AC Breaker on units | Turn on breaker and make sure prime power is present to the unit |
| Alarm present in Power/Phase Monitor | Power/Phase Monitor (FV). Only the leftmost Normal LED should be lit. | •>U/<U LED indicates the voltage is outside the acceptable range (187-252V) •Phs. Seq. LED indicates the phase sequence must be corrected •Asm LED indicates the phases need to be balanced |
| Loose/incorrect alarm wire | Alarm wiring | Verify/tighten alarm wiring according to the Three Phase AC Loss Wiring diagram. |
