Operating Guide

TROUBLESHOOTING
20 • Residen al Hybrid Electric Heat Pump Water Heater Use and Care Guide
DISPLAY SHOWS INDICATES CORRECTIVE ACTION
- -- --- (series of dashes) Unit is doing a system
diagnostic.
Normal operation--no action
ICE Heat pump is in defrosting
cycle.
HPO Ambient temperature <45°F
or >120°F, average tank
temperature of 59°F or less.
*
EUC Upper element is not
functioning
Refer to Page 22, Step 2 “Check Upper Heating Element.” and
Page 27 “Replacing the Heating Element”
ELC Lower element is not
functioning
Refer to Page 22, Step 2 “Check Upper Heating Element.” and
Page 27 “Replacing the Heating Element”
SF The air filter is dirty. Refer to “Air Filter Maintenance” page 30.
*
ECF The heat pump compressor is
starting/stopping frequently.
1. If compressor is running and fan is not operating, call
residential technical support.
2. Clean the air filter. See “Air Filter Maintenance” section
on page 30.
3. Check installation location against recommended
confined space requirements (step 2, page 9).
*
E20 or E21 Upper Temperature Sensor is
not functioning.
Power off (Power Cycling the unit, page 25), disconnect and
reconnect J2 and J5 connections from control board, inspect
wire for damage, re-install UIM, reconnect power. If error
persists, replace temperature sensor.
E30 or E31 Lower Temperature Sensor is not
functioning.
E50 or E51 Heat Pump Suction Temperature
Sensor is not functioning.
E10 or E11 Heat Pump Coil Temperature
Sensor is not functioning.
E40 or E41 Heat Pump Discharge
Temperature Sensor is not
functioning.
*
E60 Upper and Lower Temperature
Sensor are not functioning
*
Edr Not enough water in the tank
(tank not full).
Open all hot water taps in home and run until water
(uninterrupted) flows from all open hot water taps.
EPL Power supply voltage is too low. Check for loose electrical connections, refer to “Power
Cycling the Unit”, page 25
*
EDH Compressor Discharge
Temperature is too high.
Call Residential Technical Support
NOTE: The diagnostic codes listed above are the most common. If a diagnostic code not listed above is displayed, contact Residential
Technical Support referencing the number on the front of this manual.
* There may be an audible alarm associated with this error. To cancel the audible alarm, press any bu on on the UIM.
DIAGNOSTIC CODES
WARNING! Electric Shock Hazard; Disconnect power before servicing. Do not remove the plas c guard from over wiring. Do not
touch electrical wiring. Failure to do so can result in death or electrical shock.