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Tankless water heater water intermitently turns cold
I have Renai R85 tankless water heater. The issue of hot water suddenly becoming cold for a minute or two before becoming hot again occurs only in the Kitchen faucet. This does not occur anywhere else like in bathrooms etc.
I have flushed the unit and increased water temp to 130 which helped a little but the issue has not completely resolved. There are no error codes. I noticed while hot water was on the burner in the unit stopped momentarily (and water started to get cold in kitchen). It began to fire again a minute or so later. I am not sure some sensor needs to be replaced or something else might be worng. Any suggestions? Much appreciated