RV Winter Storage: Out of Sight, Out of Mind?

For most RVers, winter means putting our RVs into storage for several months, and in the upper Midwest, sometimes up to 6 months! Hopefully most of us take the typical precautions for winterizing such as adding antifreeze to the fresh water system, emptying out the water heater, and preparing for rodents! However, most RVers walk away from their stored rigs and think they can easily come back in the spring to bring them out of hibernation. Unfortunately, there are a few RV winter storage items that should be conducted throughout the maintenance process.

Batteries

RV Winter Storage

12-Volt Deep Cycle House Batteries

12-Volt deep cycle batteries are designed to provide continuous power for interior lights, roof vents, and other appliance for an extended period of time. They will be discharged from a fully charged 12.6-Volts to 10.5-Volts and recharged repeatedly which is called a “cycle”. These are different than automotive batteries which maintain a constant charge and are designed to provide a large amount of current for a short amount of time, or “Cold Cranking Amps” to start a vehicle.

Once the car is running, the alternator provides the power for the vehicle and the automotive battery just maintains its charge. Automotive batteries are not designed to be drained more than 20% of charge, otherwise they will weaken and become defective. Deep cycle batteries typically have thicker plates and higher quality materials used such as paste, separators, and grids. The house battery or batteries are designed only for energy storage. There are four different types of 12-volt deep cycle batteries:

Lead Acid/Flooded –These batteries are constructed with a hard plastic shell, lead plates, and an electrolyte fluid containing sulfuric acid and water covering the plates which is referred to as “flooded”.

As the energy is used, or the battery is discharged, lead sulfate crystals form on the lead plates. This condition is termed Sulfation and will limit the storage capacity of the plates. The lead acid battery needs a multi-stage or desulfation charge once a month that will break up the lead sulfate crystals on the plates, and then adds an equalizing and float charge. To get this type of multi-stage charge, you need a converter or battery charger that has this capability. Most converters are simply a charger that senses when the battery drops to 10.5-Volts and provides a 13.6-Volt charge until the battery reaches 12.6-Volts. This does not condition the batteries and they will become sulfated.

Most large (2000w+) inverters have this function, as well as larger solar panels with a controller. If your rig does not have this function, you will need to get a different charger, or install a Battery Minder which applies a high impact wave initially to break up the lead sulfate crystals and condition the battery. If you do not have power available to your rig in storage, you can get a Battery Minder with a solar panel, or remove the batteries and apply a multi-stage charger in your garage. If you do not have electricity and do have a multi-stage charger, you will need to go to your rig once a month and start the generator or bring a portable generator to condition the batteries which might take several hours!

One more issue with lead acid batteries. During the initial high voltage charge, the acid will actually boil and gas will emit from the vent holes which will deplete the acid in the battery. You will need to check and add distilled water once a month so the fluid level does not get below the lead plates.

Gel Batteries – The gel battery utilizes the same core construction with a gelling agent (usually fumed silica) added to the acid. This battery is totally sealed so it requires no fluid level maintenance, however it still can become sulfated and requires conditioning although much less than lead acid batteries. Therefore the Gel Battery does require the same multi-stage charging conditions as stated in the Lead Acid description above for units that are plugged into a 120-volt source, or not.

Absorbed Glass Mat (AGM) – AGM batteries are also sealed so there is no fluid maintenance and they are less prone to sulfation similar to the Gel, however not completely! AGM batteries were developed in the 1980’s with a very fine fiberglass mat to absorb the sulfuric acid for the military and UPS to provide a spill proof and lighter battery that requires less maintenance and can be shipped without a hazardous material label. They can be layered with plates similar to the lead acid battery or can be “spun” in a circular manner. An AGM battery can sit in storage without a charge longer as they have less self-discharge in colder temperatures and only need a desulfation charge every six months.

Lithium Ion – Since the late 1800’s lead had been the primary component used for battery plates in lead acid, gel, and AGM batteries. Lithium was introduced as a storage component in electronics for cell phones, laptops and other devices but had some issues with combustion situations in the early phases. The new chemically engineered Lithium Ion batteries introduced to the RV market have been proven winners and provide extended battery power and limited maintenance. However they come at a higher price point.

Generator

RV Winter Storage

If you have an on-board generator, it should be “exercised” every month which consists of running the generator under a 20 amp or more load for at least 30 minutes. This lubricates the seals and reduces varnish build up in the gasoline versions. This is a maintenance task that few RV owners do, therefore there are several cases of generators not performing well or not starting at all due to varnish build up.

RV Cover

A cover is a great idea if your rig is stored outside as it helps reduce harmful UV rays, keeps the tires from weather checking, and keeps sealants from drying up. However, heavy winds and other environmental factors can wreak havoc with covers, and they should be inspected on a monthly basis to make sure they are not torn or coming off. A torn cover can flap in the wind and cause severe damage to the side or top of an RV as well as letting rain or snow to get under the tarp.

RV Winter Storage

Other Inspection Tips

It’s also a good idea to visually inspect the unit for water leaks, rodents, odors or anything else that may be unusual to prevent it from getting worse. Last winter a local owner had a squirrel chew through the cover vent and made a nest inside the roof air conditioner. During the winter it completely chewed up the foam insulation inside the roof air, and in the spring he fired up the AC and it blew white foam “snow” all over the inside! Inspecting the rig for leaks and damage often may allow you to catch it early enough to fix or repair before it becomes major!

Discussion
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12 Responses to “RV Winter Storage: Out of Sight, Out of Mind?”
  1. Clyde Waite

    RV Make: Fleetwood, RV Model: Flair, RV Year: 2017

    How can I increase the force of air from my air conditioner??it does not provide adequate air conditioning in hot climates.

    Reply
  2. Tom Billigmeier

    RV Make: Coachmen, RV Model: Santara, RV Year: 1995

    I store my rig in a barn at our county fairgrounds, but I am unable to get access to it while in storage for the 6 month period. Should I remove the house batteries before storage and keep them on a trickle charge during thos time? I also keep the gas in the tank at minimum 1/2 full and run the generator and engine with Sea Foam in the gas while driving to storage to hopefully reduce varnish build up in the generator carb. Not sure what else I can do when unable to run the generator monthly, as you suggest.

    Reply
    • Customer Service

      Hi Tom,

      First of all I do recommend removing the batteries when in storage. Using a good battery charger like a tender or maintainer does help prolong the life of the battery and keeps the plates in good condition. As for the gas, Sea Foam can help a lot to clean out any build up that is present but to prevent it I like using Star Tron. It is an enzyme fuel treatment to help prevent the damaging effects of ethanol. I use it in all of my carb run things at home, generator, snow blower, motorcycle and lawn mower. It can be used in all gas engines and helps keep the gas in good condition. If you add this to your fuel on the regular and then run the generator while it is in the fuel, you don’t have to worry about starting it once a month during storage. It is still a good idea if able to, but having this fuel treatment does help prevent issues when not running for a while. I will post a link below with more information on the treatment.
      http://www.starbrite.com/startron

      I hope this helps!

      Dan
      RV Repair Club Video Membership

      Reply
  3. Randy Farrell

    RV Make: Cruiser RV, RV Model: Shadow Cruiser, RV Year: 2015

    As far as covering your tires during storage, I haven’t had much problem with checking but I have had other tire issues. Is it better to run on 10 ply tires than it is to use 6 or 8 ply tires. I’ve had many issues with flats in the past 2 years. Any suggestion on which Brand is the best?

    Reply
    • Customer Service

      Hi Randy,

      Ply ratings are just based on how much load the tire can handle. Today’s ply ratings are different then they used to be, an 8 ply tire now may only have a few layers compared to old tires that actually used 8. This is because of advancements in technology. They still use the ply rating to compare the strength of older tires. The ply rating coincides with the load rating. Load range C is 6 Ply, range D is 8 ply and range E is 10 ply. You want to get tires that are rated to equal or greater than what your trailer is made to handle. Upgrading to a larger ply/load rating doesn’t necessarily increase the durability of the tire, just the load it can handle. If you are experiencing a lot of flats, I would have the wheels inspected. There could be small leaks from debris on the wheels causing them to go flat. As for the durability of tires, I know Goodyear Endurance tires have been a popular choice lately and they have a good reputation. I personally have Carlisle tires on my RV and have never had a problem. There are some reliable brands out there so checking reviews and seeing what other people have experienced is the best way of finding something good.

      I hope this was helpful!

      Dan
      RV Repair Club Video Membership

      Reply
  4. jpusser

    RV Make: Newmar, RV Model: Canyon Star, RV Year: 2017

    On my Motorhome I have a battery disconnect switch for the house batteries above the entry door. Does that completely disconnect EVERYTHING from the house batteries so there is no draw from the battery whatsoever? Also, should I install a cheap battery disconnect switch on the chassis battery to keep things from drawing down the battery when in storage? I think the chassis battery holds the memory on the radio and perhaps some other items in the Motorhome. I know there have been many discussions on batteries but I am looking for advice on my specific topic mentioned above. Thank you.

    Reply
    • Customer Service

      Hello,

      The disconnect switch for the house batteries should disconnect them completely from the system. When activated, there should be now draw on the house batteries. The chassis battery can loose a little voltage over time when not in use since it has a constant connection but it won’t loose as much as the house batteries would when connected. If you have it in storage for months at a time it is not a bad idea to put a disconnect switch on it to help preserve the voltage. Taking it off and putting a battery tender on it is best to do, for both sets of batteries, but isolating them from the system does help prevent voltage loss. You will loose the memory for the radio for sure when disconnecting the chassis battery but there shouldn’t be much else.

      I hope this helps!

      Thanks,

      Becky
      RV Repair Club Video Membership

      Reply
  5. dottie1

    RV Make: winnebago, RV Model: Journey, RV Year: 2001, Brand: Onan

    Onan generator not getting power

    Reply
  6. John Sioris

    RV Make: Fleetwood, RV Model: Pace arrow 37A, RV Year: 2003, Brand: Fleetwood pace arrow, Model Number: 37 a

    House batteries are not charging when driving. Main battery charges, but not the back. What can be the cause.

    Reply
    • Customer Service

      Hi John,

      It could be something like the connections or in line fuse being bad but most likely it is the battery isolation switch. A lot of RV’s are equipped with an isolation switch. This switch is activated when the ignition starts and connects the chassis battery to the house batteries so they also get a charge from the alternator. It will be in the engine compartment and you can test this by checking the voltage on the side terminals when the engine is running and making sure the voltage is going through. If it is not, check all connections and make sure they are good and if so it may need replaced. Some RV’s have a selector switch which is different. This will be turned on to charge the batteries, some will turn on automatically when the engine starts but can be selected when parked to run slides or have the chassis battery charged when plugged in. I would check your owners manual and see what type of setup you have and then you would be able to see where to start troubleshooting.

      I hope this helps!

      Dan
      RV Repair Club Video Membership

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  7. ed litteral

    RV Make: Fleetwood, RV Model: storm 35 sk, RV Year: 2016

    when I park my rv at home I usually connect the 110v to the camper ( for the residential refer and lights) should I use the battery disconnect switch to keep from overcharging the home batteries?

    Reply
    • Customer Service

      Hello Ed,

      Most of the converters now have a built in charge system that have multiple stages. Once the battery is charged it will go into a “float charge” stage. At this stage it maintains the battery at a full charge and prevents it from overcharging. So leaving the battery disconnect switch on is actually good for the batteries.

      I hope this was helpful!

      Dan
      RV Repair Club Video Membership

      Reply