RVs have many systems and appliances that mimic their residential counterparts to some extent. They are a large part of the conveniences and comforts that make RVing attractive to so many of us. However, there are some differences between RV and residential systems you should be aware of. Knowing and respecting the differences can avoid frustration, poor experiences, and premature equipment failure.
RV Water systems are usually designed to approximate the comforts of home as closely as possible,but they have their limitations. The most basic system found in old time truck campers and small travel trailers had a single, manually operated faucet to deliver water to the sink from a jug or storage tank in the cabinet underneath. Waste water from the sink drained directly out through a pipe through the side of the camper and had to be collected in a bucket and carried away to be dumped. More advanced RVs have pressurized or electrically powered water systems and hot water heaters that literally provide hot and cold running water at multiple fixtures throughout the unit at the twist of a faucet, pretty much like at home. Waste is usually collected in holding tanks so you don't have to think very much about it -- until it is time to dump the tanks. With judicious use of water, these systems will provide performance near that which we expect at home. You probably won't have the pressure or flow you have at home, but it is usually adequate. However, we do need to consider that our water supplies are limited when dry camping and ration water usage to make sure we have enough to last the entire trip. Don't waste water by letting it run when you're not actually using it. Wet your hands, then turn off the water while you scrub. Then turn it back on to rinse. Same with the shower. Letting it run while you're lathering up just turns precious fresh water into sewage for no reason. Maintaining your fresh water system mostly consists of filling it before each trip. If it begins to develop a bad taste or bad odor it may need to be flushed and sanitized. There are additives you can put into your fresh water tank to help keep it fresh, but unless you fill it with contaminated water at some point, just rinsing it out and refilling it should usually be all that is necessary. Most city water supplies are already chlorinated so when you fill your fresh water tank from home or another city water source, it already contains some protection against bacteria. If you fill it from a private well with no chlorination you might want to add a little household bleach to sanitize it, but don't add too much! It shouldn't have a bleach odor at any of the fixtures. If it does, you've used too much. Drain and refill the tank. You don't need a lot of bleach to do the job. For example, the residue left in an empty gallon bleach container after it has been completely emptied is enough to protect all the water it can hold. That amounts to just a few drops per gallon. A few tablespoons of bleach, perhaps half a cup at most, should be enough for most RV fresh water tanks. If you can taste or smell chlorine at any faucet or in your drinking water, you've used too much bleach. You should only smell bleach at the faucets when you are sanitizing the system, not after you've flushed it and refilled it for use.
Most modern RVs have fresh water systems powered by a 12-volt water pump. The pump includes a pressure switch that automatically turns it off when there is no demand. Sometimes the frequent cycling of the pump can be annoying. An accumulator tank can reduce how often the pump has to run. This can extend pump life as well as reduce the annoying noise. Not all pumps are compatible with accumulator tanks so check whether your's is before adding one. The water pump will also have an on/off switch. If you don't get water from your RV faucets, make sure the water pump is turned on. If the switch is on, check the fuse. Also make sure there is water in the tank. If the pump runs continuously but you don't get any water the tank is probably empty. If you get water at some fixtures but not others, the problem may be a clogged fixture. Many faucets have an external screen and flow control device mounted in the very end of the fixture. You can usually unscrew the end of the faucet and clean these to restore flow. If that doesn't work, check for kinked, flattened, or broken pipes or tubing. RV water pumps come in a variety of sizes and styles. If you add or replace your pump, make sure you get one that is rated for your application. Some pumps are designed to supply a single fixture. Larger RVs will have multi-fixture rated pumps designed to supply water to more than one fixture at once. I've tried several different styles of RV water pumps, ranging from single-fixture self-contained pumps to large pumps with external motors and belts. I have gotten the most satisfactory performance from multi-fixture Flojet diaphragm style pumps. Typical RV water pumps deliver about 3 gallons per minute, enough for most activities but sometimes a little anemic for showers. Some systems include an accumulation tank to reduce cycling the pump every time you open a faucet. Some pumps are not designed for use with an accumulation tank, so check the specs on yours before arbitrarily adding one. If you are using campground hook ups, make sure the faucet is turned on and the hose connecting your RV to the faucet isn't kinked or flattened. I've seen RVers park with a tire on their own water hose and then wonder why they aren't getting any water. Speaking of water hoses, use only those designated for use with potable water or drinking water and make sure they don't create a trip hazard between you RV and the faucet. Roll out enough hose so it will lay flat between the faucet and the RV. Roll up excess hose and store it under the RV. This helps keep it out of the sun to prevent heating up the cold water as well as keeping it out of the way. Some enterprising RVers even put their hose inside a soft-side cooler pouch to further protect it from unwanted heat.
Water filters will help ensure your water is clean and palatable. You can use an inline filter when filling your fresh water tank or when connected to a campground faucet. Some RVs have permanently installed water filters in the plumbing where water from both the city water inlet and the water pump have to pass through it before going to the fixtures. In line filters are fairly inexpensive and easy to use but don't last very long and might not have the same ability to filter out contaminates (such as heavy metals) as larger filters. The in line filters are usually about 2" in diameter and a little over a foot long, with hose connections on each end. Connect the female fitting to the faucet and the then connect your potable water hose to the male fitting on the other end. Water filters designed for RV use are available at RV supply stores like Camping World, but many people have had good luck (and spent less money) using residential filters from a home center or hardware store. If you have a permanent filter on your RV, be sure to remember to drain it for winterization and to check and replace the cartridges as needed. Some luxury motorhomes have very fancy filters with features like reverse osmosis that ensure REALLY pure water, but they tend to be rather expensive and take up valuable space. You can use residential style filters in-line by adding appropriate hose fittings. Because they are kind of large and bulky you may need to stand them a crate to keep them from falling over. This will allow you to have properly filtered water without the difficulty or expense of permanently installing the filters. Sometimes there simply isn't any room to install permanent filters.
Pressurized water systems were used on many older travel trailers, truck campers, and even some motorhomes. The water tank on these units will be made of stainless steel instead of plastic. You fill them by attaching a garden hose like you would for a city water connection. As they fill the tank, the air in the tank is compressed and the system is pressurized and water will flow from the fixtures until the pressure fails. These systems are equipped with a Schrader valve (like a tire stem) where you can add pressure and some have auxilary air pumps to restore pressure between fill ups. In a pinch, you can attach a manual tire pump or air compressor (or gas station air hose) to the Schrader valve and add pressure. Don't over do it. You only need enough pressure to make the water flow. Over-filling can damage the plumbing.
City water hookups allow you to connect a potable water rated hose to a campground faucet. If the pressure and flow are adequate, you'll have residential quality water service in your RV. Kinks in the hose and debris in the filter-screen or aging and failing plumbing in the campground can seriously reduce performance. Always use a pressure regulator to protect your hose and your RV plumbing from unexpected high pressure surges. Why do you need a "potable water rated" hose? Ordinary garden hoses can leech a plastic taste into your water, especially when it is exposed to the heat of lying in the sun when no water is flowing. Potable water hoses are usually white or light blue to make it easy to distinguish them from the garden hose you might use to flush your holding tanks.
Many RVs use polybutylene (PB) pipe for fresh water lines. This a semi-rigid gray pipe that resembles plastic electrical conduit but is smaller and somewhat more flexible. Generally it gives pretty good service and is even said to resist freezing but occasionally there may still be problems. The most common source of leaks are the joints. The pipe itself may be damaged by nails, screws, abrasion, vibration, or freezing. The original connectors used for PB pipe are no longer manufactured, but certain PEX connectors can be used to replace leaking or damaged joints. One of the easiest to use is the Flair-it brand of compression fittings. Another alternative is a brass fitting called Sharkbytes. Flair-it straight connectors might be used to repair damaged sections of PB pipe. No matter what you use, proper preparation and installation is essential to ensure a leak free repair. Start by carefully cutting away the damaged components. There are specialized cutting tools for PB that are similar to those for PVC pipe. Lacking that you may be able to cut the pipe with a hacksaw. In close quarters one of the cable saws designed for cutting PVC pipe might do the trick. Make your cut as square as you can to ensure a leak-free repair. Any time you're sawing through the pipe you will likely end up with ground up plastic inside and outside the pipe. About the only way to get it out of the inside is to flush it out with water or blow it out with compressed air. Residue on the outside should be wiped away before installing the new fitting. Remove the nut from the fitting and side it onto the pipe, taking care to keep the open end where the threads are toward the place the fitting will be installed. Press the fitting onto the pipe, then slide the nut in place and tighten it. When the repair is complete, pressurize the line and look for any leaks. Sometimes simply tightening the fitting a little more may take care of the problem, but be sure not to over-tighten the nut which may break or otherwise damage the connection. Some folks have had success using modern PEX piping for repairs. For best results, look for special fittings that adapt PEX to PB.
Sanitation systems are the second component that allow us to have residential style fixtures in our RVs. Plumbing is similar to that in our homes, but the waste is captured in holding tanks. Water from sinks and sometimes the bath or shower goes into a gray water tank. Toilet waste goes into a black water tank. Sometimes the shower is also fed into the black water tank. This is done for two reasons: 1) increase the liquid in the black water tank to facilitate decomposition and dumping and 2) reduce filling the gray water tank. Residential systems are typically attached to city sewer lines (or septic tanks in rural areas) and we usually don't have to worry too much about over-filling them. RV holding tanks have very limited capacities and we definitely DO have to worry about over filling. An over filled gray water tank is an annoyance and inconvenience. An over filled black water tank is a serious problem, one that is VERY unpleasant and can create serious health hazards inside and outside your RV. Minimize holding tank usage whenever you can by taking advantage of fixed facilities in campgrounds and by limiting water use while dry camping. Black water tanks need to be regularly dumped and rinsed and treated with appropriate chemicals to keep them healthy. The chemicals help break down solid wastes and control odors. Gray water tanks usually only need to be dumped and thoroughly rinsed. However, over time an accumulation of food particles from washing dishes and from soap residue may cause odors in the gray water tank. If this happens, add some of the same holding tank chemicals you use for the black water tank to the gray water tank or buy special gray water treatment chemicals. It shouldn't take nearly as much as the black water tank to be effective.
Sewer system problems can be annoying and even unhealthy. Make sure your dump valves are completely closed and the cap is securely in place. Some dump valves hang down low behind the rear wheels and are sometimes subject to being damaged going in and out of driveways or by other obstacles you may encounter on rough or unpaved roads. Be aware of where your dump valves are and take care to avoid obstacles that might damage them. If you get some seepage through the dump valves you will need to replace the seals or the entire valves. You may notice drips from the capped dump port or you might not notice the problem until you remove the cap to dump the tanks. If the valves have been leaking, removing the cap can deliver a very unpleasant surprise, especially if it is the black water thank that was leaking! Always remove the cap slowly and carefully. Be sure the port is over the dump station sump or place a bucket or plastic dishpan under the port when removing the cap. Catching any spillage will avoid a messy clean up that you'll face if the crap flows onto the ground. Occasionally you may experience a minor drip from a loose connection on one of the sewer pipes. Sometimes the connections are secured by hose clamps and simply tightening the hose clamp may solve the problem. If there are no clamps or if tightening the clamps doesn't solve the problem you may need to have the problem diagnosed and repaired by a qualified RV technician. Any repairs beyond tightening clamps can only be done when the tanks are empty, so it is necessary to find a way to dump the tanks before attempting repairs. Faulty dump valves can usually be rebuilt or replaced by any fairly competent home mechanic. Replacing the seals solves most problems unless the valve body itself is cracked or the handle is broken. Broken components will require complete replacement of the valves. To replace the seals, remove and disassemble the valves. Remove the old seals and carefully clean the grooves in the valve before installing the new seals. Warming the new seals in hot water prior to installation may make it easier to fit and form them into place. Take care when reassembling the valves to avoid pinching or otherwise damaging the new seals. More common than leaks are odor problems. Proper dumping and rinsing of holding tanks and use of appropriate chemicals will prevent most problems. If you smell sewer odors when driving with the windows open, try closing the windows. Sometimes air passing over the windows will create a partial vaccum inside the RV, drawing odors up through the toilet or the plumbing. Make sure you have a water seal in the toilet (keep the deep well of the toilet about half full). Another common source of odors from the gray water tank is a relief valve. If the odors are strongest inside a bathroom or kitchen cabinet, the relief valve is probably the source. It is supposed to be a one-way valve to allow air into the drains to avoid sucking all the water out of the P-traps. If the valve gets stuck open it can allow odors to waft back up into the unit. A stuck valve can sometimes be cleared by lightly tapping the valve body, but take care not to hit it too hard. It is made of plastic and if you crack it you'll have more than unpleasant odors to deal with. If light tapping doesn't solve the problem you may have to replace the valve. If you are familiar with PVC plumbing you should be able to cut out the old valve and plumb in a new one. If you aren't comfortable with how to do this, have it done by a qualified RV technician.
Full hookups in an RV park can be confusing to some people. New users often think they can simply hook up the sewer hoses and use the facilities as if they were at home. It doesn't work that way, especially in the black water system for the toilet. If the dump valves are left open, liquid drains away and solid wastes in either the gray or black water systems, can get left behind, creating deposits that affect performance and create foul odors. When using hookups, fill your tanks about 1/2 to 3/4 full before opening the valves and dumping them. That usually provides enough pressure and flow to flush out solid wastes as well as giving holding tank chemicals time to break them down. It is especially important to keep the black water valve closed until the tank is about half full. Otherwise the crap may pile up on the bottom of the tank and eventually clog the toilet! Some people leave the gray water valve open, but it makes more sense to me to also leave it closed until to time to dump so it can flush the hose after dumping the black water tank.
You RV toilet looks a lot like the one at home, but there are significant differences. First, instead of a tank that stores 3-5 gallons of water for flushing, it flushes with water sprayed directly into the bowl from the fresh water supply. This saves a lot of water, but it sometimes means you need to take a little extra time to clean the bowl. Keep a toilet brush handy or even a stick you can use to wipe; use toilet paper on the stick to wipe down the surfaces. This simple task will help keep your toilet cleaner and odor free. An RV toilet is usually flushed by a foot pedal instead of a lever. The foot lever opens the door in the bottom of the toilet and activates the water flow. Press it all the way down to allow waste to drop into the holding tanks. You have to learn to balance conserving water with using enough so that solids don't build up under the toilet. I suggest that, as a minimum, fill the hole in the bottom of the toilet before flushing any solids. If you find you're getting build up below the toilet, use more water. Holding it down part way will allow water to continue to flow after the door is closed so you can clean the bowl and leave a few inches of water in the well at the bottom to ensure a seal against holding tank odors. Cleaning the toilet can be done much as you would at home, but most RV toilets are made of plastic instead of china so avoid caustic cleaners and harsh cleansers. Soft-scrub cleansers, like BonAmi and Barkeepers Friend, are OK for stubborn stains, but don't rub too much. If you do you'll damage the surface and the stains will get worse over time. You might also try cleaning discolored toilets and toilet seats with a paste made from vinegar and soda. The seal on the door in the bottom needs to be cleaned periodically too. Shut off the water supply (turn off the pump or shut off the faucet for the city water connection). Press the flushing pedal all the way down and carefully clean the seal. Some new toilets come with a specially designed brush. If you don't have one, an old toothbrush or grout brush can be used. I have seen people clean the groove in the seal using a bent coat hanger. If you have to resort to this method, make sure there are no sharp edges on the wire and be VERY careful not to damage the seal. Clean the edges of the sliding door as well and make sure there is no debris in the seal or on the door before you close/release the pedal. You may need a helper to turn on the water for you for rinsing before you release the pedal. If you don't have a helper, prepare ahead by bringing a bottle or pitcher of water to use for rinsing. The plastic lid on RV toilets are subject to fading and discoloration. Fellow RVers have offered a number of tips for keeping them looking good. Routine cleaning with a Mr. Clean Magic Eraser is said to be a good preventative measure. For those that are too faded to be cleaned, you might restore the finish by painting the lid with vinyl plastic paint, available in hardware stores and home centers. Be sure to remove and previous waxes or other coatings and prepare the surface according the instructions on the can. Cracked or broken lids and seats should be replaced although small fractures might sometimes be successfully repaired using plastic-solvent type glue, a process known as chemical welding.
Most RV water heaters function very much like residential heaters but are much smaller. Homes typically have one or more 50 gallon water heaters. Most RVs have single units with a capacity of 6 to 10 gallons. There are also "on demand" heaters that can provide continuous hot water, but they are not typical. Ordinary tank style heaters can be replaced with tankless, on demand heaters, but they are relatively expensive --at least 2 or 3 times the cost of a standard replacement heater. Most all RV water heaters run on propane. Some have auxiliary electric heating elements to help reduce propane consumption when connected to shore power or running the generator. Some have instant water heaters that quickly heat water on demand instead of keeping a tank of water heated. Instant water heaters may run on propane or electricity. Two advantages of instant water heaters are 1) they only consume energy when there is a demand for hot water and 2) they can deliver a continuous supply of hot water as long as there is water and energy to run them. Some RVs use hot water from the engine to pre-heat the water in the hot water heater. Its a really useful feature, but not often found. The primary maintenance for tank style water heaters is to make sure the burner is clean and properly adjusted. The flame should be large and blue. If it sputters or is yellow, the burner needs to be cleaned and/or adjusted. Most RV water heaters have a sacrificial rod mounted on the inside of the drain plug. This rod is designed to absorb the chemical action that would corrode the tank. It should be checked periodically and replaced when 75% of the material is gone. The biggest difference between RV and home water heaters is capacity so you'll need to ration or limit hot water usage. Do NOT waste water, especially hot water, rinsing dishes. Wipe them off with paper towels or used paper napkins or old newspaper before washing. Don't waste water by letting it just run while washing your hands, brushing your teeth, or showering. Turn it on only when needed to get wet or to rinse off soap. Don't let it run while you are shampooing or scrubbing. One trick is to save water in a plastic dishpan while running the shower to get it warm and use that for other tasks, such as rinsing dishes. Some innovative motorhome manufacturers connect the heater hoses from the engine to pre-warm the hot water tank during travel. Kind of a clever idea. You pretty much always have hot water on the road and when you arrive at camp -- and at no additional energy cost! If you live where you get freezing weather, a water heater bypass system will simplify winterization and save 6-10 gallons of antifreeze. Just remember to turn the valves back to normal before you try to use the water heater again next spring. You could damage the water heater if you turn it on when it is empty.
RV stoves may or may not include an oven. They work very much like residential gas stoves only smaller. They may have from 1 to 4 burners. Some have electronic ignition systems but many have to be lit with a match or lighter. Light your match or lighter first and then hold it near the burner while turning on the gas. Turning on the gas first may release excess gas into the living space, resulting in an explosion when you attempt to light the stove. Some RV cook tops keep a pilot light going after you shut off the burner so you can restart the burner without needing a match or lighter. If yours has pilot lights, make sure the pilot lights are out before filling the gas or propane tank. RV ovens are smaller than the ones at home and usually lack the timers often found on residential ovens. Keep the size in mind when purchasing your Thanksgiving turkey to make sure it will fit! Maintenance mostly consists of cleaning the stove top, burners, and oven. The oven can be cleaned with ordinary household oven cleaner. Use an all-purpose household cleaner on the stove top. If you have stubborn deposits, be careful not to damage the surface by rubbing too hard with steel wool or plastic scrubbers. "0000" steel wool works pretty well on stainless steel if used carefully but can easily damage painted or porcelain surfaces. Better to apply a strong cleaner and let it soak for a while. Make sure all the openings around the burner are kept clean. Clogged openings will significantly reduce burner function and efficiency. Not only will this increase cooking times and gas consumption, it may create unhealthy fumes. By the way, you may have heard you can clean and polish stainless steel appliances with vegetable oil. Don't do it! It may leave nice shine when you put it on but it soon becomes a rancid residue that will be difficult to remove. If someone in your household has already done this, it will take a strong kitchen degreaser and a lot of elbow grease to get back down to the native shine. I picked up some all purpose wipes at my local dollar store that also worked pretty well, but it still takes a lot of elbow grease to get that crap off.
Microwave/convection ovens are quite popular in modern RVs. In most cases they are essentially the same as residential units, but may be smaller than the one you're used to at home. They require 120-volt AC power so you need to be connected to shore power or have your generator running or have an inverter and a massive battery bank to use them. Maintenance consists mostly of keeping them clean, same as at home. They will NOT function well on low voltage, which is often a common problem in older campgrounds or if the on board generator isn't adjusted properly. They may not function properly on cheap inverters that use "modified sine wave" power. Units designed for RV use will generally last longer than residential units installed in RVs. They are usually designed to withstand vibration and power fluctuations common in RVs better than residential models. Some microwaves come with special RV installation kits that make them more suitable. The installation kits usually include baffles to help vent heat properly and a facia that both holds the oven in place and give it a nice, finished appearance.
RV refrigerators are usually gas absorption models. They operate differently from home models that typically use electrically powered compressors to power the cooling units. You may find it curious that your RV refrigerator is actually cooled by a flame! Unlike a compressor driven system, it has no moving parts. If you really want to know how that works, look up "absorption refrigeration" on Google or Yahoo. Some large luxury motorhomes these days use a regular residential refrigerator. That means you have to be connected to park power or running your generator to use them, unless you they run off of an inverter backed up by a HUGE battery bank. Your RV fridge should function pretty much like the one at home to make ice, keep frozen foods frozen, and keep perishable foods at a safe temperature. To take best advantage of your RV fridge and avoid things inside it getting too warm, limit opening the door(s) as much as possible. There are cooling fans that can be added to increase the efficiency of the outside coils and fans to help circulate air inside the unit. I like using a solar-powered outside fan since it doesn't draw any battery power. You can buy replacement roof vents for most refrigerators that include a solar powered exhaust fan. There are also battery-powered fans (brand name Fridge-Mate) to circulate the air inside the fridge. These are available both as self-contained units powered by a couple of "D" batteries and as hard-wired units that connect to your RV's 12-volt power supply. Don't over-pack your fridge. If things are too tightly packed, the air cannot circulate and you will have hot and cold spots -- some items in the fridge may freeze while others spoil. Just like your hot water heater, the burner assembly needs to be kept clean and properly adjusted. The burner assembly is accessed through an exterior panel behind the refrigerator. Most modern RV refrigerators have electronic ignitions controlled by a computer board. Older models may have a pilot light that must be manually ignited. Always follow the manufacturer's instructions when lighting pilot lights. Failing to do so can result in fire and/or explosion. My father-in-law lost his eyebrows and his enthusiasm for camping when he tried re-lighting a pilot light too quickly. If you find your fridge isn't keeping things cold enough check the temperature setting knob and turn it to a colder setting. If there is a lot of frost buildup you'll need to defrost the unit to improve efficiency. Minimize opening the door and let hot foods cool before you put them inside. Poor performance and excessive frost build up may indicate a bad door seal. Close a one dollar bill or similar paper in the door at various places all around. If it falls out or comes out without any resistance, the seal may be faulty. You should be able to feel a little resistance when you try to pull it out if the seal is closing correctly. Replacement seals are available for most RV refrigerators.
Defrosting your RV refrigerator. Most RV refrigerators are not frost free and will need defrosting periodically, especially at the end of a trip when you store your RV again. How quickly frost develops depends on several factors, including humidity, how much high moisture food you put in it, and how often the door is opened and for how long. Avoid opening the door or keeping it open when you can. That will reduce frost in the freezer and preserve the temperature in the refrigerator cabinet for better performance too. If the frost in the freezer compartment gets to be 1/4" deep or thicker, you need to defrost it to ensure proper performance. NEVER use sharp tools to scrape away the frost. You can puncture the cooling lines. If you smell ammonia, you have a leak in the cooling system. That will probably require having the entire cooling system replaced. Don't use a hair dryer or heat gun to melt the frost in your freezer compartment. It can melt plastic and even warp metal parts. Allow it to defrost gradually. Check for frost often and won't wait until it gets much beyond 1/4" before defrosting. The task will be faster and easier and your fridge will work better. Keep an eye on the "run off" as the frost melts. It should be caught in a tray beneath the freezer compartment. If it overflows, you're going to have a mess! If you need to accelerate melting, place a pan of warm water in the freezer compartment.
RV Furnaces operate pretty much the same as your home furnace but they are limited by availability of both propane and 12-volt electric power. Most modern RV furnaces have electronic ignition systems so all you have to do is turn on the switch and set the thermostat. Some older units have pilot lights you have to light manually. Be sure to read and follow the manufacturer's instructions carefully when lighting pilot lights. My father-in-law burned off his eye brows when trying to light the furnace in an older motorhome when he became impatient and tried re-lighting too soon instead of waiting the recommended 5 minutes between attempts. Fortunately his eyebrows and his ego were the only casualties of his experience. Others have not been so lucky and have lost their RVs and even their lives. Some older units may be "convection" furnaces that don't have 12-volt fans. They don't distribute the heat as effectively but they don't run your batteries down either. RV furnaces require little routine maintenance. Make sure all the vents are kept clear -- outside vents supply air to the burner and allow the hot byproducts of combustion to escape. Inside vents deliver warm air throughout the RV.
Any blocked vent can have a negative effect on both furnace efficiency, performance, and safety. If you wake up in the middle of the night and your furnace fan is running constantly but blowing cold air, you may have run out of propane or, interestingly enough, your batteries may be low. When the batteries get low, the electronic controls don't work right and the fan will continue to run after the burner has shut off and further deplete your batteries. If this happens on a regular basis you need to upgrade your battery bank, reduce your furnace use, or add some auxiliary heat.
RV Air conditioning systems may include both dash and roof A/C units. Dash air in a motorhome (or tow vehicle) is the same as that in your car and runs off the vehicle engine. Dash air in a motorhome provides comfort for the driver and copilot while on the road but is not enough to cool the entire coach. Roof A/C units run off 120-volt electric power, from campgrounds or your on board generator. Traditionally these blow cold air directly into the coach interior through adjustable vents on the inside face plate of the unit. More recently, ducted versions have come into usage that direct the cold air more efficiently to various parts of the RV. No matter which style you have, you will want to minimize the load to conserve energy and maximize comfort. Keep doors and windows closed. Keep drapes, curtains, or shades closed. Use reflective foam insulation to cover windows and windshields to keep out heat and sunlight. A/C maintenance mainly consists of cleaning the inside filters (most units have an easily accessible foam pad behind the vents) and keeping the outside condenser fins (looks like a silver radiator) clean and straight. Bent or dirty fins can restrict airflow and decrease efficiency and performance. Some older units have motor bearings that need to be oiled but most modern systems have sealed bearings. You can run your generator and use your roof A/C while traveling to maintain comfort on the road.
An alternative to air conditioning sometimes found in RVs is an evaporative cooler. They are lighter than 120-volt A/C units and run solely on 12-volt power -- plus water. Be aware they don't work well in high humidity or when the outside temperature is below about 85°F. The water reservoir in some models is subject to spilling over during sharp turns and dousing the occupants. If that happens about all out can do is turn off the water supply and drain the reservoir so it is empty while traveling -- and forgo the cooling.
12-volt electrical systems power most of the lights and appliances inside your RV. Your furnace fan and water pump both run on 12-volt electric power. This power comes from three sources: your RV automotive alternator, 12-volt batteries, or via the converter from 120-volt power via your shore cable or your RV generator. One other option is solar panels. Motorhomes are usually set up with two battery systems: one for starting the vehicle engine and a second bank of one or more batteries to power the coach. Both sets of batteries are charged by the vehicle alternator when the engine is running. The house batteries in a travel trailer
may be charged by the vehicle alternator if the trailer connection is wired for it. If you have a trailer and/or tow vehicle without this feature, it can be added at a modest cost. Anytime you have two battery systems there should be a battery isolator to allow the vehicle alternator to charge both systems but to prevent the coach from drawing down the starting battery. I have seen motorhomes with three or more batteries: a vehicle starting battery (or battery bank), a generator starting battery, and a coach battery bank, but most have just two: vehicle and coach. A nice feature is an "Emergency Start" switch that temporarily connects both systems together. This can be used to start the generator if the coach batteries are too discharged to do it or to start the engine if the starting battery is weak. When you have multiple battery banks you should have a battery isolator to keep the battery banks from scavenging power from each other but still allowing all batteries to be charged by the vehicle alternator. The battery isolator allows current to flow from the alternator to all the batteries, but keeps the load for each battery bank separate so you don't run down your starting battery using 12-volt lights and appliances in your coach. Maintenance of your 12-volt system will focus on keeping the batteries and connections in good condition and fully charged. See my previous post on
Battery Maintenance for particulars. There will usually be one or more 12 volt outlets where you can plug in fans, phone chargers, and other accessories. If you don't have any, or they are not conveniently located, you can usually add them as needed.
120-volt electric systems power a variety of things in our RVs. 120-volt power comes from your shore power cord when hookups are available or from your on board generator when boondocking or on the road. Roof A/C systems are the primary system that runs directly on 120-volt power. 120-volt power also feeds the converter that converts it to 12-volt power to run lights, etc. Most converters also have a battery charger circuit that helps recharge RV batteries, but these chargers are not usually very powerful or efficient. It is often better to buy an automatic automotive style charger and set it up to charge your batteries whenever you have 120-volt power available. Some advanced converters and inverters have good multi-stage chargers that do a much better job of re-charging and maintaining batteries. A third source of limited 120-volt power is the inverter. This a device that converts 12-volt DC power into 120-volt AC power. There are small, portable inverters that plug into a 12-volt, cigarette lighter type receptacle, and if they are of an appropriate capacity and the vehicle wiring is adequate can power radios, computers, etc. Larger units, up to say, 2000 watts, are permanently mounted in some RVs and can power larger 120-volt equipment and appliances. Just remember they are drawing down your batteries, so unless you have a HUGE house battery bank, you can run your batteries down rather quickly using inverter power. I would definitely NOT recommend using inverter power to run 120-volt lights. It would be very inefficient. It is handy to run a can opener, blender, or hand mixer for a short time, when you don't want to or can't run your generator. TVs and other entertainment systems usually draw too much power for it to be practical to run them off an inverter for extended periods unless your battery bank was specifically designed to meet that kind of power demand but they can be handy for short periods of use. If your motorhome or trailer is not equipped with an on-board generator there are portable generators you can purchase, if you have room to transport them. One possible advantage to a portable unit over an on-board generator may be the ability to move the generator some distance from the coach to reduce noise and exhaust pollution inside. Just make sure you aren't intruding into someone else's space!
Some large luxury RVs have even more residential style appointments, such as dishwasher, trash compactors. ice makers, washer/dryer setups, and refrigerators. Usually the only special considerations are limited size and the need to keep an eye on consumption of resources (water and power). There is a growing trend to using residential style electric refrigerators in large luxury RVs. These units are usually equipped with a large battery bank and a high watt inverter. You may have trouble finding a place for enough batteries to retrofit an older RV for this option.
Entertainment systems could be as simple as an AM radio or as sophisticated as a complete home entertainment system. I upgraded the AM/FM radio in my truck camper to an AM/FM Stereo/Cassette player with built in equalizer. My Class A motorhome has two TVS, with external over-the-air and satellite antennas and a combo VCR/DVD player. It also has a port to attach cable TV if it is available in a commercial campground. Many high end motorhomes and trailers have home theater systems that rival anything you'd find in an upscale residence. Your main consideration in using entertainment systems will probably power consumption. Satellite systems can be added to just about any RV. The easiest and least expensive systems are portable systems that you set up outside when you arrive at your camp site. Next are roof mounted antennas that you align once the RV is stationary. For the ultimate in convenience and access, there are roof-mounted systems that automatically track the signal and can be used while traveling. Of course, these fancy automated systems are quite a bit more expensive than the other options. With any satellite antenna you'll need a receiver and a subscription to a satellite service like Dish Network or Direct TV. It may be possible to temporarily move your home receiver to your RV, but it is a lot more convenient if you have a dedicated receiver in your RV. You can usually get special "pay-as-you-go" accounts to use with your RV so you're not paying for your subscription all the time, even when you RV is sitting unused at home.
Backup cameras are found on some RVs, usually on large luxury motorhomes. Modern systems may even include side mounted cameras that are automatically activated when the turn signals are used. Backup cameras are essential on large diesel pushers that have no rear window but are great asset when backing just about any RV. There are backup obstacle detection systems that use a technology similar to radar or sonar to detect obstacles and sound a warning. Given the limited view behind most RVs, any kind of camera or warning system would be advantageous. Modern technology even offers wireless cameras that don't require running a wire from the camera to the monitor, making installation very easy. If you don't have one, it is a good idea to have a person act as a ground guide when you're backing up to prevent accidents.
Camping with full hookups will affect how you use your on board systems. Having shore power eliminates the need to run your generator and lets you use your lights and appliances without fear of running down your batteries. Being connected to city water means you don't have to run your 12-volt pump and that your water supply is more or less endless. Being connected to a sewer at an RV site makes sanitation easier, but you can't just hook up the hoses and forget about it. The black water tank should be allowed to fill about half way and then dumped. It isn't a bad idea to do the same with the gray water tank but it isn't as critical. If you leave the valves open, any liquids will drain away and leave solids to dry out and stick in your holding tank. So, even with full hookups, you will need to monitor holding tank usage.
Go ahead! Rough it easy!
