Help-Water Tank Won't Drain

Open a faucet to help break the vacuum.

Yes, sounds like your tank has a vacuum right now. Opening a faucet will not help, because the air has to somehow flow from the faucet, back through your water pump and then into the tank. The pump is sealed, air will not flow backwards. Good idea, wrong method.

Disconnect the in-take water line on your water pump. THAT will break the vacuum, and probably break free the vacuum in your pump as well. It's quite obvious the pump is stuck (with pressure on it).

That will help you drain the tank, but something caused the vacuum in the first place. Your vent to the fresh water tank is closed up, stuck, or something stuck in it not allowing it to vent. That's probably the real problem.

Do you have a manual low point drain either along the bottom or bottom side of the tank?

Told you it was something simple. I started up the coach and the vibration must have broken an air lock. I can't see where the outlet is, but it must be on the lower side of the tank. It seems to be very sensitive to having a level coach. The tank has an over flow which should provide venting either for the pump or the drain. Thanks for the help.

Great! Glad it was an easy fix! Now you can relax and enjoy the winter (oh, did I "really" say that?)...ugg.

You likely could have opened the gravity fill to break the vacuum lock

Inspect your vent line, Often these are next to the gravity fill line, make sure there are no kinks or obstructions.