How to Bypass a Hot Water Tank to Winterize a Cabin

Turn off the breaker that controls power to the hot water tank to prevent any electrical accidents while you bypass the tank.

Fill the antifreeze tank with a nontoxic antifreeze if your water tank has such an option. Many water tanks in cabins and RVs include it to make winterizing a more efficient process. All you'll need is 2 or 3 gallons. This saves you the trouble of having to fill the water tank itself with antifreeze.

Open the relief valve on the tank and drain both the water tank and the heater by hooking a hose up to the valve and filling a bucket with the water that pours from the relief valve. Close the valve and dump out the bucket, as needed, until the water tank is empty.

Turn off the water pump. Switch the winterize valve to the "winterize" position and the bypass valve to the "bypass" position.

Turn the pump back on and turn on the hot water faucet in the cabin that is farthest away from the tank. Run it until antifreeze starts to come out of the faucet. Turn off the faucet once about a cup of antifreeze has gone down the drain. Do this for all the other faucets in the cabin as well as any showers, bathtubs and toilets.

Turn off the pump again, then turn on a hot and a cold faucet to let out any remaining pressure in the system. Close them once you don't hear any more hissing. The tank is now bypassed and the cabin's plumbing is winterized.