10/10/2026
We have had a number of customers in the store for RV winterization supplies, and they have had a few questions about how to winterize their RV water system. Getting the water out of your RV system can save a lot of grief and repairs in the spring if it is not stored in a heated space. This is a basic explanation of a couple techniques that have worked for me.
The Blow-Out Method:
1. Drain the main water tank.
2. Drain the hot water tank.
3. Open any "low point" drains that your RV is equipped with and drain until no water comes out.
4. Run your water pump until it loses its prime.
5. Close the bypass valves on your hot water tank.
6. Connect an air line to your "city water" inlet with no more than 20-30 psi of pressure.
7. Open your faucet valves and let air purge the water from the line until all you hear is air flow. Then close the faucet valves
8. Step on your toilet flush valve until all you hear is air coming through the valve into the toilet.
9. Remove the air line from your city water connection. Open a faucet valve to make sure there is no pressure remaining in your water system.
10. Pour enough RV antifreeze into your sink traps to displace any water.
The RV anti-freeze method:
1. Drain the main water tank.
2. Drain the hot water tank and close the bypass valves.
3. There are two possibilities for your coach to put antifreeze into the water system. First, you can use a hand pump connected to your city water connection (not the gravity fill) OR your coach might be plumbed at the water pump with a suction line specifically for pulling antifreeze into your system.
4. Using either your hand pump or the water pump as described above, charge your water system with the RV antifreeze straight from the bottle. Do not dilute it.
5. Open each faucet on your coach until water is purged and pure antifreeze is coming out. For sinks, run enough antifreeze into the sink to displace water fill the traps with RV antifreeze. Then close all faucet valves.
6. Keeping the water system charged with antifreeze, flush the toilet until pure antifreeze is coming onto the toilet bowl.
Those are the basics for your water system. Don't forget to drain your black and gray water tanks. It is also a good idea, if electricity is available, to make sure batteries are topped up with distilled water, close the battery disconnect switch, and connect a battery trickle charger direct to the batteries. Not all chargers are created equal; make sure it is designed for trickle charging of deep-cycle batteries. "Battery Tender" is a common brand specifically for this purpose.
Good luck and don't hesitate to give us a call or a text if you have a question. We currently have RV anti-freeze and a few of the anti-freeze pumps, as well as the blow out fittings in stock in the store.
Dan 509-690-2580
