Boiler Fault Code 73:0

Also written as 730 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026

Fault code 73:0 appears across 1 boiler brand and 5 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler's hot water pump is scheduled to be running, but it may not be operating correctly or is being flagged for an advisory check. (As reported on Viessmann Vitodens 300-W)