I am Going on vacation for two months during the winter and plan on shutting off the water to the house. I have a Rheem tankless water heater mounted on the wall in the solar. I need to know what should be done when I shut the water off. Can I leave it as is? Do I need to kill the Power and leave it as is? Just want to do what is right. There will be heat in the house while we are gone

If there is a heat in the house while you gone - then I would not worry about tankless. Otherwise, I would recommend to shut off the tankless at the isolation valves and open both H/C drain valves to drain it

Hope that helps

Milo

Hi Coubie

Shut off the water at the main shut off as planned and then shut the power off to the tankless heater at the breaker at the electrical panel or at the service switch located close to the unit if present. Draining the tankless heater is up to you (certainly can't hurt), but should not really be required here. When you return, flush the water system by running water at all fixtures for a few minutes each, flush all toilets and then you can turn the power back on and should have hot water readily available after that!

Mark