Originally Posted by 97Powerstroke
When it gets warmer I will put the valves in bypass and filled the lines with water. I will verify the water heater doesn't fill up with water. It's not that I don't believe you guys but I always like to see for myself!
Good chance to inspect/renew the tank annode. With the cold inlet closed, no water should come from the heater with the bypass left open. This will allow water from a hose to fill the cold system and cross over to the hot side. The heater check valve should keep the tank from filling (out the annode plug).