RV 101: De-Winterizing Your RV

RV Water System

There are two important tasks we want to accomplish when we de-winterize the RV water system:

1. Remove the RV antifreeze from the plumbing system.
2. Sanitize the RV water system so it is safe to use.

Let’s get started:

Flush the RV Water System:

If you used non-toxic RV antifreeze to protect the water system from freezing you need to run fresh potable water through the entire plumbing system until all traces of the RV antifreeze are removed. To do this connect a potable water drinking hose to the city water connector on the RV and run fresh water through the entire plumbing system, to include sinks, shower, outside shower, toilet, and washing machine if applicable. After all traces of the RV antifreeze are removed you can reinstall any water filter cartridges that were removed for winter storage. The RV antifreeze that was in the plumbing system is now in the gray and black water holding tanks and can be emptied when you have access to a suitable waste disposal site. After the plumbing system is flushed you can take the water heater out of the by-pass mode, if applicable. If the water heater wasn’t bypassed, the water heater tank is full of antifreeze and needs to be drained and collected in buckets or other suitable containers.

Note: If non-toxic RV antifreeze was added directly to the fresh water holding tank when the unit was winterized, the first step is to drain any remnants of antifreeze from the tank.  Try to drain the antifreeze into a bucket or container so it doesn’t drain directly on the ground. Next, add potable water to the fresh water holding tank, turn the 12-volt water pump on and open all of the water faucets. When you see clear water running throughout the system turn the water pump off and close the faucets.

Sanitize the RV Water System: 

Make sure all of the drains are closed and any drain plugs are reinstalled. Take a quarter-cup of household bleach for every fifteen gallons of water your fresh water tank holds. Mix the bleach with water into a one-gallon container and pour the solution into the fresh water holding tank.

Note: If your RV does not have a fresh water fill location you can pour the water/bleach solution directly into one end of a potable RV drinking hose that is connected to the RV prior to connecting the opposite end of the hose to a potable water supply.

Fill the fresh water holding tank completely full of potable water. Turn the water pump on and run water through all hot and cold faucets until you smell the bleach at each tap. Close the faucets and let the solution sit in the fresh water holding tank and water lines for at least twelve hours. Drain all of the water and re-fill the fresh water tank with potable water. Turn the water pump on and open all faucets, running the water until you no longer smell any bleach. It may be necessary to repeat this process to eliminate all signs of bleach.

Now we can focus our attention on other items on the RV that can be affected by cold weather storage.

RV Batteries:

Battery condition is dependent on how well the batteries were cared for during winter storage. When batteries are in storage they lose a percentage of current through internal leakage. A battery can discharge up to 10% a month when it is in storage. Note: If you removed the batteries for storage reinstall them, making sure they are connected properly. If you checked and recharged the batteries while in storage they should be ready to go. If not, the first step is to fully charge the batteries. Water should only be added to lead-acid batteries after fully charging the battery unless the water level is already below the plates. The plates need to be covered at all times. After the battery is fully charged check and add distilled water as required.

Caution: If you are not comfortable working on or around batteries have battery maintenance done by an authorized RV repair facility.

RV Appliances:

Open the LP gas valve at the cylinders or tank and check the operation of all LP gas fired appliances. Make sure the water heater tank is full of water prior to testing the operation of the water heater. If an LP gas appliance is not operating properly have it inspected by an authorized RV service facility.

Note: The LP gas system should have a drop pressure and operating pressure test performed annually. These tests should be performed by an authorized RV repair facility.

After checking the LP gas appliances for proper operation plug the RV power cord in and test all 120-volt appliances and accessories for proper operation. Make sure you have an adequate electrical source (30-50 amps depending on your RV’s electrical system) prior to testing items like the microwave and roof air conditioner(s).

RV Tires:

Just like the battery loses a percentage of its charge while in storage, tires lose a percentage of air pressure while in storage. Your RV tires can lose two or more psi a month sitting in storage. Check the tire pressure using a quality tire inflation gauge and adjust the inflation pressure to the manufacturer’s recommended inflation pressure based on the load.

Tip: Tire manufacturers publish load and inflation tables to assist in proper inflation pressure.

Engine & Generator

If you have a motorized RV check all vehicle fluid levels. Consult your vehicle owner’s manual for proper fluid levels. If a fluid level is low try to determine why and correct the problem. Start the engine and check for proper readings on all gauges.

If you have an onboard generator check the oil level and service the generator according to specified intervals found in the generator owner’s manual. Inspect the generator exhaust system for any damage prior to starting the generator.

Caution: Never run a generator with a damaged exhaust system. Carbon Monoxide is colorless, odorless and deadly. If you didn’t use a fuel stabilizer in the fuel system and the generator won’t start, or it continues to surge after starting, have it checked out and repaired by an authorized RV service facility.

RV Safety Items:

Re-install any dry-cell batteries or fuses that were removed from safety devices for storage. If batteries were not removed it’s a good idea to replace the batteries now. Test the operation of the carbon monoxide detector, LP gas leak detector and smoke alarm. Inspect all fire extinguishers to make sure they are serviceable and fully charged. Recharge or replace fire extinguishers as required.

This is a good start to de-winterizing your RV, but there are other checks that should be made in conjunction with de-winterizing your RV, like inspecting seams and sealants and cleaning the interior and exterior of the RV. You can add items to this list to suit your particular needs and prepare your RV for another fun-filled camping season.

Happy Camping,
Mark J. Polk
RV Education 101