Tankless water heater repair with the fault code already in hand

Tankless units report faults as codes, and the code is the starting point, not the diagnosis. A code 11 on a Rinnai tells you the burner did not light; it does not tell you whether the cause is a closed valve, low gas pressure, air in a new line, a fouled flame rod, a failed igniter or a board fault. CANRO's technicians test gas supply pressure, ignition and flame signal, the condensate trap and vent, the inlet filter and flow sensor before replacing parts.

Repeated lockouts and temperature swings are often maintenance issues in disguise: a scaled heat exchanger, a blocked inlet screen or a full condensate trap. Where that is the case, the repair becomes a descaling visit and the manufacturer's service reminder is set so it does not recur.