Last year saw record numbers of people becoming proud RV owners, with more than 40,000 vehicles shipped in June 2020 alone. If you’re new to the RV lifestyle, you may be wondering where to start with some of the terminology and information on offer. This guide to HVACs is designed to give you the confidence to run and maintain these essentials so that you can brave winter chills and keep your cool in the summer with ease.
What’s an HVAC?
Your RV’s HVAC is the Heating, Ventilation, and Air Conditioning system, similar to what you may have at home. Part of the joy of RV ownership is the freedom it gives you to travel and explore: 90% of RV owners take three or more mini-breaks per year in all sorts of weather conditions, so it’s important to be able to keep the temperature to your liking. This leaves you feeling relaxed and comfortable enough to take in the views and make memories with your family in style.
Keeping Your Cool
Since 2020 saw one of the hottest summers on record, you may be most concerned with the air conditioning in your new RV. The unit for this is likely to be stored in a rooftop box, which maximizes space inside your vehicle. Air conditioning power is measured in BTUs (British Thermal Units). The higher the rating, the more powerful the air conditioning. Put simply, the system picks up hot air in the RV and passes it via refrigerants – chemical coolants – which take the heat from it. The process converts gases to liquids and vice versa, so it’s crucial that you clean the unit regularly to reduce the risk of mold building up inside. While you may find it helpful to fit a hygrometer to measure humidity (another factor for causing mold), your RV will already be fitted with a digital or analog thermometer. Some can be zoned so that the temperature in different parts of the RV can be controlled independently.
Winter adventures
Since many RV owners love to hit the road come rain or shine, spending three or four weeks a year in their vehicle, RVs are also equipped with heating and insulation to cope with colder weather. The warm air will either be produced by a heat pump, which uses electricity, or a furnace, which runs on propane. Your heat pump is likely to be located in the rooftop AC box. If you are camping somewhere with power, it can be a good idea to plug in and use your heat pump to save on propane, but in extreme cold, the furnace tends to be a more effective and efficient way to keep your RV cozy and warm.
Looking after your HVAC
While Coach-Net is always ready to help its members, with a little maintenance you can ensure that your RV is always as ready for adventures as you are. Use a handheld vacuum to clean dust from your HVAC’s vents regularly. For the AC unit, check for signs of fluid leakage, and ensure that you clean the filters regularly too. If your RV has a propane furnace, ensure that you have a carbon monoxide detector fitted in your vehicle and that the batteries are up to date. Finally, on the occasions when you are carrying out rooftop maintenance, keep an eye on the condition of the plastic casing in which the AC unit sits.
Owning an RV opens the door to all sorts of trips, but it can feel a little daunting as you get to grips with how best to take care of it. Systems like your RV’s HVAC are there to make your journeys more comfortable, so it’s important to learn how to control the settings to your preferences, and to maintain the system so it can continue to look after you. Now, you’re free to explore – whatever the weather.
Teresa S. ~ “Your agents are always pleasant and helpful! They always impart a feeling of calm. And your techs have helped us each time we had an issue with our coach. They are very knowledgeable and walked us through our issues. Solved our problem every time!!”
This is also a good time to clean the top of any slide rooms or the awning if there is one available. Check with your awning manufacturer for recommended cleaning products and conditioners.
It’s always a good idea to read the instructions when you purchase a new item. An RV cover is no exception to this rule. Consult the instructions to ensure you put your carport cover together correctly, or to make sure you’re securing your fabric cover the right way.
Regardless if you are washing a trailer, fifth wheel, or motorhome, step one is to assess and make any necessary changes to your cleaning area. Make sure you have adequate drainage. Park on a relatively flat surface since you will be climbing up and down a ladder. Plus, close all vents, windows, and doors tightly to prevent any water from entering the unit.
Just like with the RV’s surface, use a cleaner that is meant to be used with the type of tire rim. Cleaning tires is altogether a different story as some products do more harm than good to the rubber. Using a mild detergent is the safest route. In addition to washing the rims and tires, use this time to thoroughly inspect your tires for wear and tear.
Opting to wash your RV regularly keeps your home-on-wheels looking its best. It can also help prevent unnecessary water damage or other disasters since you are inspecting the condition of the RV multiple times a year. The dirty truth about keeping your RV clean is simple. Be good to your rig, and you will reap many more miles and adventures than you could possibly handle!
An RV furnace requires almost no maintenance. If necessary, clean or vacuum out the ducts if they get dusty or dirty. Regularly inspect the furnace intake on the outside of the RV for debris, insects, or other restrictions. Restrictions in the air intake can cause incomplete combustion. The by-products of incomplete combustion are Carbon Monoxide (CO) and soot. CO is an odorless, colorless, toxic gas. Incomplete combustion can be indicated by the presence of soot on the furnace exhaust on the outside of the RV. However, this is not a given and is another reason to have your system annually inspected.
This diagram shows the typical setup for most roof air conditioners. The motor spins the fan, or “squirrel cage” which draws air from the interior of the coach up through the air return vent. The air is pulled through the evaporator coil while the compressor pumps a refrigerant through the lines zig-zagging through the evaporator. A chemical reaction occurs which flashes and draws heat from the air as well as moisture. The heat is absorbed by the coolant which flows back to the condenser which draws air from the outside to dissipate the heat. The moisture pools in the evaporator pan shown below and run out the two weep holes on either side.
When our owner told me it was not cooling, I asked him what was the ambient temperature inside the rig, and what was the temperature blowing out of the AC vents? His reply; “ I don’t know, it was warm inside the rig because the AC wasn’t working, just blowing warm air?” One thing we always stress at the RV Repair Club, when trying to troubleshoot always take specific measurements and not rely on generalities. Temperatures, voltage, airflow, all that information helps identify issues and helps technicians understand what is happening without being there.
If the outside temperature was over 90 degrees, the inside temperature could be even higher if the unit is sitting in the sun baking. And sure enough, his rig was at the State Park Campground sitting out in full sun for most of the day because he needed a line of sight for his satellite receiver! Ouch. Most roof air conditioners can only “condition” the air down 16 degrees during a full cycle which could take over an hour. So if you start with an ambient temperature inside of over 100 degrees it will take most of the day to get down to a comfortable interior temperature if everything is working properly! Find a shaded area, this can reduce outside temperatures by over 20 degrees! If you need to get a satellite signal, consider a portable dish that you can put anywhere.
What does the refrigerator have to do with the air conditioning? The more your refrigerator runs, the more heat it generates in the cabinet and inside the rig. Check and clean the roof vent so hot air is able to rise and vent rather than sit and swelter inside the back cabinet. Make sure the refrigerator is cooling at the highest efficiency so it’s not running all the time.
Slide rooms require very little maintenance, however, if there is debris such as sticks or acorns on the top of the slide and they are retracted, the rubber seal will be compromised and moisture penetration could occur. When bringing your rig out in the spring, run the slide rooms out and inspect the roof material, rubber seals, look for any leaks. Make sure all rubber seals are installed properly and making contact. This is also a good time to condition the rubber gaskets with an approved treatment such as these ProtectAll products
Deep cycle house batteries need to be properly stored with either a charge from a multi-stage charger during storage, or have the batteries removed and properly charged in a garage or shed. In the spring, it’s time to check lead-acid batteries for proper fluid level and either reinstall them or clean all the posts and connections and apply a protective spray. Make sure all battery cables and wires are in good condition and not chewed or compromised by rodents.
Since the water used in your freshwater tanks typically would be hard water from a campground source, it is a good idea to sanitize the system using ¼ cup bleach in a gallon of water for every 15 gallons of freshwater capacity. Fill the tank and run all faucets for approximately 10 minutes. If you do not like the smell of bleach, Thetford makes a freshwater tank sanitizer as well.
Typically RV owners do not remove the LP tanks or cylinders during storage, however, it’s a good time to check all connections for leaks. Make sure you open the valve slowly to allow LP to flow at a reasonable rate and not activate the excess flow valve. After opening the valve, test your LP leak detector to make sure it is operating properly. You can use a liquid test solution to test all connections at the appliance, or HomeFlex makes an electronic tester that is available at most home improvement stores.
