Draining the Water and Drying the Water Lines
- Allow all water to drain from the fresh water holding tank. To drain the water from your RV, you'll need to open what's called the "petcock." Do not be tempted to drain the water heater yet -- that has to be done after you add antifreeze.
- Drain the black and gray holding tanks. You should also flush both tanks at this time.
- If your RV does not come equipped with a built-in system, you should clean the tanks out with a wand or a product designed to clean both of the tanks.
- Take all the tanks' contents to your local dump station.
- Flush your toilets a few times to make sure all the water's gone!
- Technically, it's attached to the "Water Intake Fitting."
- Pressure should be 30 pounds per square inch (maximum of 50 psi).
Adding Antifreeze to the Plumbing System
- Choose your method of adding antifreeze. There are three ways to do this:
- From the inside using a water pump conversion kit.
- From the outside with a hand pump.
- With or without a bypass.
- We'll be addressing the water pump with a bypass method. The science behind the pumps is the same. However, without a bypass, you just have to add much, much more antifreeze. Regardless of whether or not you have a bypass, do not drain your water heater before adding the antifreeze.
- Turn off the water heater.
- Disconnect the water supply (the above step).
- If installing for the first time, disconnect the hot and cold lines going in and out of the water heater.
- Connect the bypass, following the instructions on the package.
- Close off the same hot and cold lines and open the bypass.
- Approximately 2 to 3 gallons (7.6 to 11.4 liters) of antifreeze should be enough to fill the RV’s entire plumbing system, provided a bypass is installed. If you don't have one, you need as much antifreeze as the water heater can hold, usually 6 to 10 gallons.
- The general order is kitchen sink, bathroom sink, shower, toilet, and outdoor shower. Run each of these until you see a strong shade of pink in each.
- You may need to flush the toilet several times until the RV antifreeze comes out at a steady rate.
Completing the Final Details
- Remove all food, laundry, and valuable items. Kind of a big duh, huh? The last thing you want is an exploded two-liter of orange soda all over your fridge. Not to mention mice and ants.
- And as for valuable items, why would you leave them in an RV for six months? And the laundry, well, it's just best to leave everything clean so when you come back in the spring, there's a lot less work to do.
- Check the entire RV for places that bugs or animals may be able to get into. Just because you're not using it doesn't mean they should get to!
- You may want to put rags on top of the sharp corners of your RV so that breathable material doesn't rip. For good measure!
- Be sure to open the pressure relief valve when draining the water heater. Allowing the water to drain while it is under pressure, or hot, can lead to injuries.
- Never use automotive antifreeze in the lines of an RV, as this can cause damage to the plumbing system.
Things You'll Need
- Pump (water or hand)
- Bypass kit (optional)
- Antifreeze (minimum 3 gallons)
- Tank-cleaning wand
- Tarp of breathable material
- Air compressor
- Adapter ("blowout plug")
Sources and Citations