On the covered Noritz tankless water heater, 11, EC11 means an ignition failure: the unit recognizes a demand for hot water but cannot ignite, or it ignites and fails to detect the flame with the flame rod. Noritz says it usually means no spark or insufficient gas. First, look through the small sight glass while a tap is open to see whether the burner is failing to ignite or failing to detect flame.
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0 of 2 completedWhat to do first
ReversibleLook through the small sight glass while a tap is open to see whether the burner is failing to ignite or failing to detect flame.
Correct only the documented fault domain
ReversibleNoritz says the ignition rod most often has build-up preventing a spark; it can be pulled out and cleaned with the rough side of a sponge, or replaced if it is badly corroded or pitted. Other causes are failed high-voltage cords, a failed igniter and, least likely, the circuit board. If you have spark, the cause is lack of gas from the meter, regulator, line, shut-off valves or an earthquake shut-off valve, which Noritz says to leave to a professional. If the unit lights briefly but still shows 11, clean the flame rod, check the blue wire on it, and check the green ground wires.
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What does 11, EC11 mean on a Noritz tankless water heater?+
An ignition failure: the unit recognizes a demand for hot water but cannot ignite, or it ignites and fails to detect the flame with the flame rod. Noritz says it usually means no spark or insufficient gas.