THIS PROCEDURE MUST BE PERFORMED BY A QUALIFIED TECHNICIAN.
THIS PROCEDURE MUST BE PERFORMED BY A QUALIFIED TECHNICIAN.
Error 20 occurs when there is a loss of communication from one circuit board to another. This may be caused by a loose connection of one of the interface cables, a defective interface cable, or a non-responsive circuit board. When troubleshooting Error 20, it is best to de-energize the Steffes heating system, disconnect and reconnect interface cables from the circuit boards one at a time, and then energize the heating system again. This will clear the Error 20 message if a loose connection was the cause. If the error message persists, examine the interface ports on each of the circuit boards for damage.