troubleshooting
CT ExprEss sTEp by sTEp opEraTion MANUAL • 51
This section is provided for the assistance of qualified technicians only and is not intended for use by
untrained or unauthorized service personnel. If your Alto-Shaam® unit is not operating properly, check the
following before calling your Authorized Alto-Shaam Service Agent:
☛ Check that unit is receiving power. Circuit breaker turned on?
Do not attempt to repair or service the oven beyond this point. Contact Alto-Shaam for the nearest
authorized service agent. Repairs made by any other service agents without prior authorization by
Alto-Shaam will void the warranty on the unit.
When the oven malfunctions, an error code will appear in the display.
PRESS THE START ICON TO ACKNOWLEDGE THE ERROR.
The icons that begin to flash represent operational modes that are still usable.
When the oven fault is corrected, the Combitherm will return to normal operation.
Error
Code
Error Call Out in Display Description of Error Possible Cause
E01 Low Water boiler Low water level in boiler — Water supply is shut off.
— Low water pressure.
— Generator drain cap/hose missing or leaking.
— Generator drain pump is defective.
— Generator drain pump elbow leaking.
— Fill solenoid not energized.
— Fill solenoid faulty.
— Wiring or connection error at the solenoid or the
relay board.
— Water level probe connection/wiring error at probe
or relay board.
— Water level probe requires descaling and/or
replacement.
E02 Control Temperature High relay board surface
temperature too high
— Cooling fan(s) not being energized.
— Cooling fan(s) faulty.
— Wiring/connection error at cooling fan(s).
— Faulty relay board.
E03 Convection Fan Motor Error Convection fan motor failure — Motor VFD not energized.
— no input signal to VFD from relay board.
— Motor VFD faulty, not outputting to motor after input
signal received.
— Motor fan wheel blocked/obstructed.
— Connection/wiring error at VFD, motor, hall effect
sensor, relay board.
— Faulty motor.
E04 Lower Convection Fan Motor
Error
Lower convection fan motor
failure on 20•20 unit
— Motor VFD not energized.
— no input signal to VFD from relay board.
— Motor VFD faulty, not outputting to motor after input
signal received.
— Motor fan wheel blocked/obstructed.
— Connection/wiring error at VFD, motor, hall effect
sensor, relay board.
— Faulty motor.
E05 VFD Comm Failure VFD communications have
stopped
— Loss of power to VFD.
— VFD malfunction.
— Can cable disconnected.
— Can address not correct on VFD.
ERROR CODES(Continued on next page)