I hope someone has an answer for this. For some reason I can't add water to my freshwater tank. When I tried to put antifreeze in the tank..it comes back out almost as fast as I try to put it in. I tried bypassing the hot water tank with the valve and also had the pressure relief valve open. I thought maybe if I had all the faucets open I would be able to put in antifreeze that way. I started with 6 gallons and lost probably 2 gallons on the ground that forced itself back out of the filler hole. Once I had 4 gallons in..I closed all the faucets except one. Then I turned on the pump. I got some antifreeze in only that one faucet. I did try all the others...no luck. Another thing that happened was antifreeze was coming out where I connect my water hose on for city water. I estimate right now I will lose the toilet and bathroom sink due to freezing..and maybe all the hot water lines. This is a 2004 Prowler.