First, empty and flush out your holding tanks. This process is expected to protect your water lines and appliances from freezing and then bursting during winter months. Drain your fresh water tank and your water heater (leave the drain plug out of your water heater until spring). Your water heater will drain a little faster if you open a couple of hot water taps in your unit! Do NOT open the safety valve on your water heater because it might not seat properly again. This will cost you when you need to replace it in the spring!

By-pass your water heater either by purchasing a water heater by-pass kit which costs about $30.00 or by removing the two water lines on the back of the water heater and joining them together with a temporary by-pass.

Blow your water lines out with air pressure (don't exceed more than 40-50 psi) you would do this with a blow-out plug. Buy a small air compressor or use gas stations air compressor used for filling tires. One person should hold the air hose on the blow-out plug which you have screwed onto your city water connection while one person opens the faucets, hot and cold, plus toilet flush, one at a time, until no water comes out.

Put 2-3 gallons of non toxic antifreeze (pink color NEVER green) through your RV plumbing system. Disconnect the water line from your fresh water tank at the pump side and use a separate suction line sold by some rv parts departments, or a pump winterizing kit consisting of a brass three way valve and suction line which stays attached to your pump permanently. Put the suction hose in the jug of antifreeze making sure it goes all the way to the bottom of the jug, with faucets turned completely off and your water heater by-passed, turn on your water pump. Open the faucet farthest from the pump. Wait until you see the antifreeze come out at a steady flow, turn off that faucet and do the next one, until you have done them all. Make sure to flush the toilet until it comes out steady. If your unit has an outside shower run the anti freeze there too.

Now pour a cup of antifreeze down each sink drain and bathtub shower drain to ensure your p-traps don't freeze. Turn the water pump off. Open all your faucets and toilet valve by sticking something in the hole.