18
DIAGNOSTIC CODES
DISPLAY SHOWS
INDICATES
CORRECTIVE ACTION
UPPER ELEMENT
CONNECT
FAULT
1. Upper element is not
functioning
1. Turn off power at the circuit breaker/fuse box and check for
a loose connection at the element. For access directions
see “Heating Element Replacement” section. If error persists
proceed to the next step.
2. Replace non-functioning element. See “Heating Element
Replacement” section.
LOWER ELEMENT
CONNECT
FAULT
1. Lower element is not
functioning
1. Turn off power at the circuit breaker/fuse box and check for
a loose connection at the element. For access directions
see “Heating Element Replacement” section. If error persists
proceed to the next step.
2. Replace
non-functioning
element. See “Heating Element
Replacement” section.
IMPORTANT:
Using an element greater than 2000 watts in
place of the lower element will damage the water heater and
void the warranty.
HEAT PUMP
CONNECT
FAULT
1. Heat Pump compressor is
not functioning.
1. Contact a qualified person to service the heat pump.
FAN
CONNECT
FAULT
1. Heat Pump fan is not
functioning.
1. Contact a qualified person to service the unit.
AMBIENT TEMP
SENSOR SHORT OR
OPEN
OR AD ERROR
1. Ambient Temperature
Sensor is not functioning.
1. Contact a qualified person to service the unit.
UPPER TEMP
SENSOR SHORT OR
OPEN
OR AD ERROR
1. Upper Temperature Sensor
is not functioning.
1. Contact a qualified person to service the unit.
LOWER TEMP
SENSOR SHORT OR
OPEN
OR AD ERROR
1. Lower Temperature Sensor
is not functioning.
1. Contact a qualified person to service the unit.
DISCHARGE TEMP
SENSOR SHORT OR
OPEN
OR AD ERROR
1. Discharge Temperature
Sensor is not functioning.
1. Contact a qualified person to service the unit.
COIL TEMP
SENSOR FAULT
OR AD ERROR
1. Coil Temperature Sensor is
not functioning.
1. Contact a qualified person to service the unit.
MAIN CIRCUIT BOARD
FAULT
1. Main Circuit Board is not
functioning.
1. Contact a qualified person to service the unit.
HIGH TEMP
LOCKOUT
1. Water temperature in unit
has exceeded 190° F.
1. See “Safety Shut-off” section.
CONDENSATE
DRAIN
ALARM
(If Accessory Condensate
Pump is Installed)
1. Condensate pump failure.
1. Check to see if accessory condensate pump is plugged in and
has power. Also check circuit breaker/fuse box and GFCI (if
used). if error persists proceed to the next step.
2. Check condensate pump outlet tube for blockage. if error persists
proceed to the next step.
3. Check control wire connections to condensate pump. If error
persists proceed to the next step.
4. Replace accessory condensate pump. If error persists contact a
Qualified Person.
LOW WATER
LEVEL ALARM
1. Not enough water in the
tank.
(Tank not full)
1. Fill Completely - Open all hot water taps in home and run until
water (uninterrrupted by air) flows from all open hot water
taps.
COMMUNICATION
ERROR
1. No communication between
mainboard and user
interface board.
1. Contact a qualified person to service the unit.
