6 Steps to Winterize Your RV's Plumbing System

An RV with snow around it.
  • 2-4 hours
  • Beginner
  • 75-150
What You'll Need
Non-toxic antifreeze
By-pass kit (water heater)
Cleaning tool
Converter kit (water pump)
Basic tools

It's never too early to start making your checklist in preparation of winterizing your RV. You don't want to wait until the last minute, and you don't want to be rushed and forget a step or two. The goal is to protect the RV from winter's harsh elements throughout the season. Check your list carefully to make sure you have the proper plan of action for your RV to be ready to roll in the spring.

The Owner's Manual is Your Friend

Before starting the winterizing process, be sure to read the owner's manual as it will have information and instructions pertinent to your RV model. Once you've read through the manual, follow your checklist, and incorporate any of the following steps that apply.

Step 1 - Drain Tanks

An RV in the winter.

There are three tanks that need to be drained — the fresh water tank, the black water holding tank, and the gray water holding tank. Begin the process by draining the fresh water tank first. You must check whether the RV has inline water filters. If they are in place, they must be removed prior to starting the draining process. One the fresh water tank is drained, proceed to the black and gray water holding tanks. A cleaning tool will come in handy for RVs not equipped with a tank flushing system. There are over-the-counter products that can take care of cleaning the tanks. Once the tanks are flushed and cleaned, apply WD-40 to the termination valves.

Step 2 - Drain the Water Heater

The water heater must also be drained. This requires caution as you do not want to drain the water heater when it is under pressure and hot. If the water heater is in a state where it can be drained, use a hand tool to remove the drain plug. You will then adjust the pressure relief valve to an open position.

Step 3 - Clear the Lines

Two RVs in the winter.

This next step is to ensure all water is removed from the lines. Do this by turning on all hot and cold water faucets in the kitchen, bathroom, shower, as well as the toilet valve. To drain water from low lying lines, engage the water pump. The pressure from the pump will help clear the lines. Once all the lines are drained, disengage the water pump, turn off the faucets, and replace drain plugs.

Step 4 - Manage Water Heater

It's important that the water heater is bypassed before antifreeze is introduced to the lines. If your RV is equipped with a bypass kit, follow the instructions for using it. If the RV is not equipped, purchase a permanent or temporary bypass converter kit, and install it. Once activated or installed, the converter prevents the water heater from overfilling with antifreeze through the water lines.

Step 5 - Add Antifreeze

RVs in the winter.

Once all lines are drained and the bypass kit is engaged for the water heater, it's time to install the converter kit, also referred to as a winterizing kit. Place the tubing from the kit into one of the non-toxic antifreeze containers. Turn on the water pump to pressurize the lines. Now you’ll begin the process of introducing the antifreeze into the lines replacing empty containers as needed.

Work from the closest to the furthest faucets. Begin with the kitchen faucets then move to the bathroom faucets and flush the toilet until antifreeze is visible. Finally, take care of the outdoor shower. When all areas have been checked for antifreeze, shut off the water pump, and turn on one of the faucets so that pressure in the lines is released. As an added measure, pour about a cup of non-toxic antifreeze down the kitchen and bathroom sink drains and the bathroom shower drain. Pour about two cups of antifreeze into the toilet then flush, which adds antifreeze to the holding tank.

Step 6 - Do a Final Check

Once you've ensured antifreeze is in all the lines, do a final check to be sure all faucets are in the closed position. For instructions on winterizing a washing machine or your refrigerator's ice maker, consult the owner's manual.

Following a few basic steps can help protect your RV from unnecessary damage during the winter season. While there may be similarities among RV models, there are also differences which is why it is recommended that you follow the instructions in your owner's manual. This checklist is a great start to ensuring your RV will be ready for another travel adventure once spring has sprung.

Dispose of non-toxic antifreeze properly. While non-toxic antifreeze is less hazardous than standard antifreeze, check with local recycling locations for information on where it can be discarded safely.