Originally Posted by LML
Is this an item you have to get from RV store or are they standard item you can get from Home Depot?
Good morning LML,
Should be able to find it at Home Depot. Itís installed where hot water comes out of your water heater. To winterize youíd manually close the in-flow valve and drain the hot water heater. The check valve is supposed to stop the anti-freeze from back flowing into the water heater. If your installation has the space to do so, replace the check valve with a manual valve just like the other manual valve. Itís a tight space to work in and youíll need your big wrenches.
In my limited experience the check valves have very poor quality and fail way too often. YMMV.