A longtime camper, Dan has experience with tents, pop-up trailers, camp trailers, and motorhomes.
Winterizing An RV
Winterizing an RV is not particularly difficult, but there are many facets to consider and many people don't cover all the bases they really should; they don't really know how to winterize an RV. Obviously, the water system needs winterizing to prevent freezing and bursting water pipes, but parts of the chassis need attention, the interior should be considered, and the propane system and refrigerator require care.
Any RV owner can do the work; it is mostly a matter of knowing what to do and which areas should be getting a little TLC. This article is broken into sections to make it a little easier to use as a checklist; if a particular section does not apply to your RV, just skip over it and go on to the next.
Winterizing an RV Water System
There are two approaches to RV winterizing when it comes to the water system; using a special RV antifreeze and emptying the system of water. In practice, a combination of both methods is probably the best.
RV antifreeze is a special antifreeze solution that is at least semi-edible. This does not mean, of course, that you can drink it, but the small amounts inevitably left in the system won't hurt you either. To use the antifreeze method, the fresh water tank is filled with enough antifreeze solution (normally ½ antifreeze and ½ water) for the onboard pump to pick up and distribute to all areas of the water system. With the antifreeze in the fresh water tank, run the pump with the furthest water valve held open until the characteristic pink color comes from the faucet. Make sure that both hot and cold water faucets are opened one at a time so that both lines are filled with solution.
With the farthest water outlet producing antifreeze solution, shut it off and proceed to the next furthest, again running both hot and cold. Continue the process until each outlet has produced antifreeze solution. Take care that all outlets are covered; easily forgotten are outside spigots, icemakers, hot water dispensers, water filters and the like. All it takes is one forgotten water source and water lines may burst. Don't forget toilets, hand sprayers, tubs and showers. When finished it is a good idea to drain the hot water tank completely by opening the petcock on the heater with a hot water faucet turned on but the water pump turned off.
With large motorhomes or trailers, this can be difficult in that the water lines and tank can be quite large and require large amounts of antifreeze. A better solution is often to blow the lines empty of water. Fittings are available (pictured below) that attach to the fitting on the RV where the pressurized water from the campground normally goes and that will accept an airline fitting used to fill tires. An air compressor of some kind will be necessary; this is a good time to splurge on buying an air compressor for use around the home.
With the fitting installed and the air compressor attached (make sure the air pressure is no higher than 40 psi) open the petcock on the hot water tank and drain it. When nothing but air is coming out, close the petcock and proceed to each other water outlet one at a time. Make sure to empty both hot and cold lines in each case. When finished once again blow out the water heater to double-check that water has not drained into it during the process.
Finish the Water System
Whichever method is used, there may well be areas that need additional care. Pictured is a stand-alone ice maker; without actually making ice during the process the water lines will not drain. The answer is to disconnect the water input and allow the water in the lines to drain out. Some RV's have a "drinking water" spigot with a water filter that should be removed and allowed to drain all the water out. A good idea is to disconnect the water line coming into the water pump and allow that water to completely drain as well.
If the blow out method has been used, each drain must still be filled with a small amount of antifreeze solution; if it is not the P-trap under the sinks and/or tub may well contain water that will freeze and break the trap. A mixture of ½ water and ½ antifreeze is best as pure antifreeze will freeze at a much higher temperature than the mixture.
The RV Chassis
Preparing the RV chassis for extended storage requires consideration of several different areas:
- Batteries. The best battery storage is to charge them completely and remove them from the RV. They should be stored in a warm, dry area on wooden blocks. Never leave a battery for extended periods on a concrete floor. If the batteries are to be removed, take extreme caution when disconnecting them and always remove the ground (-) cable first. The arc from an unintentionally grounded positive cable connected to several batteries can be enormous. Batteries may also be left on a trickle charge all winter, but make sure the charging system is designed for this and check the water level in the batteries periodically. Motorhomes of any type may have several batteries; the RV pictured above has 3 coach batteries and 2 engine batteries. If batteries are to be left in the RV without a trickle charge the positive (+) cable should be disconnected; most RVs have some parasitic power usage that will drain the batteries otherwise and allow them to freeze and crack.
- Tires. Tires need protection from sunlight - most RV tires fail from dry rot and cracking, not from actually wearing out. Covers are available for many tire sizes, but a simple piece of plywood fitted inside the tire well will work as well. If possible, park the RV on wooden blocks or in some way raise the tires completely off the ground
- Turn off the propane system. Even a small pilot light left on will eventually empty the propane tank and go out, with a resulting propane leak. Make sure that all propane appliances are turned off as well as the main valve.
- Empty holding tanks completely, particularly gray and black water tanks. If possible, empty the fresh water tank as well, or add antifreeze until the contents of the tank are about half and half antifreeze and water.
- This is a good time to do any scheduled (or unscheduled) oil changes on both RV engines and generators. Check any air filters and replace them as necessary. Verify that the engine coolant is a good antifreeze mix.
- Check the exterior of the RV for any cracked caulking that might need to be replaced or other exterior damage that could conceivably let rain or snow into the RV.
- Gasoline tanks, including possible generator gas tanks, need to have protectant added to prevent the gas from going bad. Run all engines after adding the protectant to get it throughout the gasoline system. Diesel tanks do not need any help here for the few months of winter.
- If possible, cover all vents. Bees and other insects will nest in such things as awnings, exterior refrigerator cavities and bathroom, refrigerator or furnace vents. If they are not well screened, a covering is a must.
Winterizing the RV Interior
Again, there are several considerations here.
- Make sure there is no access to the interior for rodents or insects. Seal all openings and double-check that all windows are closed. It is all too easy to leave a bathroom vent or driver's wing window open all winter.
- Open refrigerators and freezers. There is often a built-in latch for keeping them open for extended periods but if not block them open. Mold and mildew can ruin a $1,000 refrigerator. Clean the interior of any refrigerator, freezer or icebox with a damp cloth.
- Pull all window shades to keep sunlight from entering. A good suggestion is to use a windshield cover if applicable. UV rays will eventually degrade upholstery if not blocked.
- Remove all food from the RV - freezing will often degrade even canned food and any bagged or boxed materials will attract animals looking for a handout.
- Empty all water containers such as ice cube trays and let dry.
- Remove all personal care items, particularly liquids. Bedding, clothing and such things as hair brushes can safely be left in the RV being winterized if the RV is impervious to rodents, insects, etc.
Double Check Everything
A last walk around to check the exterior of the RV completes the winterizing of your RV. Make doubly sure that doors and windows are closed and locked. Check that the outside storage compartments are shut and locked. Are cords, awnings or accessories left out? Are tires aired up and not flat? If a security system is present is it turned on and running (only if the battery charging system is operating - otherwise it will drain the batteries)? If there is any chance at all that awnings were put away wet or even damp, open them up and allow them to dry thoroughly. Don't forget any window awnings or the smaller ones over slide-outs.
All of this may take several hours, mostly in the water system, but it is certainly time well spent. Failure to know how to properly winterize your RV can result in massive damage and it is a chance to give it a good inspection for damage or other problems. With a little experience, you are more likely to spot problems than an RV shop anyway; it is your rig and you know it better than anyone! If actual RV repairs are needed, the RV can be taken to the shop then. Nearly all "camping homes" need to be winterized; even a tent can probably stand a good airing out before its long winter rest. Learn to do your own and put the savings into a new portable gas grill to take on your next camping trip come spring!
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.
Questions & Answers
Question: Does the inside propane tank have to be full when winterizing my class A rig?
Answer: No. It doesn't make any difference how much is in it - just make sure it is turned off in case there is a leak anywhere. And make sure any pilot lights are off - one year I left my oven pilot on and it drained the tank over the winter, then when there wasn't enough propane to run even that small flame the flame went out and began to set the propane detector off. As we hardly ever use the oven it was hard to find the "leak".
© 2010 Dan Harmon