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Rinnai Burner Shut Off When the Cover is On
Rinnai RU98i REU-KB3237FFUD-US, installed Aug 2014
Here is strange situation my plumber is trying to solve. When the cover is installed on the unit, with hot water demand, the burners run for a short period of time, then cut off, then sometimes come back on, then off. Sometimes code 12 is displayed. A code 10 was displaced once. If then cover is not installed, the unit runs just fine with both low and high demand hot water. Vent piping checked OK. This situation occurs even if the vent pipe is removed. Gas pressures checked OK. Regulator vent plug OK but was replaced. Even with the vent plug not installed the same thing occurs. The flame rods and igniter were cleaned.
It might be coincidence or not, but if the unit is running and then you go to install the cover, sometimes jiggling the cover or installing the screws seem to trip the burner. Rinnai rep does not believe this is an electrical short issue but I have might doubts.
Anyone have any thoughts?