I have found a work around ,I run the water pump while showering I think it adds some cooler water from the tank and keeps the pressure up so I can add cold water with the handle without losing pressure and the heater kicking off. Plus seeing how I added the shower miser valve for boon docking,If the heater does kick off I can flip the valve until warm again then flip the valve back to shower,and when I'm done I use the valve to refill the tank.
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