Tankless Water heater turning on

[dewhitsel]

I have a 2024 Cougar 23MLE fifth wheel with a tankless water heater. I have the unit stored for the winter, and I had the water heater power turned off. However, I noticed that the power was somehow turned on, with an E1 code showing, indicating the gas source was missing, since I also had the gas valve closed. I turned the gas on to clear the error, and then turned the power to the water heater off again. The next day I noticed that the external fan on the water heater was running. When I checked the power inside the unit, it was back on and had the E1 code again. Is it normal for the unit to "check" for a propane source regularly, even though it is "off", and to turn itself back on? I recently opened the panel on the water heater and turned it off using the toggle switch on the water heater itself, but I'm still wondering why it kept turning itself back on and running the fan.

 

[NH_Bulldog]

It is going into “winter” mode. Unless you turn it off on the water heater itself, it will still have power and will still run in this safety mode regardless of the remote control panel. It is a design feature that briefly activates the water heater when water temperature in the unit drops to around 35° and shuts off at 48°. It will continue to cycle on/off until ambient temperature stays above the lower set point.

The big question is whether you cleared the system of water with compressed air and/or antifreeze. There is no bypass on these units and the water must be cleared in freezing weather or severe damage will result.