Care and Feeding of your RV Refrigerator or Camp Cooler

RV and other portable refrigerators provide us with ways to preserve perishable foods on the road and in camp.  They approximate the features and functions of your home fridge, but their operation and capacity are much different.  Most residential refrigerators use electrically powered compressors for cooling.  Most RV units are gas absorption models that run on propane.  Funny to think that a flame is used to cool things!  If you're interested in just how that works, look it up on the Internet.  Basically, the flame provides the energy to circulate the coolant.  Gas absorption refrigerators need to be kept pretty level for proper operation.  Newer units are less sensitive than older designs, but leveling your RV is still necessary for efficient operation.  Leveling isn't an issue when the unit is in motion so climbing or descending hills won't cause your RV fridge to malfunction. The problem with being off level when stopped is that liquid coolant can pool at low spots in the system and block circulation.  Proper leveling in camp  or movement when you're on the road, avoids this problem.  Some portable refrigerators, including ice-chest sized ones used by truckers and tent campers, us a different technology.  These units can often be used as either warmers or coolers, depending on the switch settings.  They operate on 12-volt DC power using thermo-electric devices that act like heat exchangers to take heat out of or put heat into the food compartment.  Depending on the setting you can keep your pizza warm or your beer cold.

Many of the principles for best performance for RV refrigerators and ice chests are the same. First, whenever you can, cool down the unit before putting anything in it.   For an RV fridge, turn in on a day or two before departure.   For ice chests, put a bag of ice in them a day ahead.   Sacrificing one bag of ice to chill the cooler will improve performance, keeping food cooler longer.  Make sure all the food is cooled before you put it in either an RV fridge or an ice chest.  At home, cool everything in your home fridge.  On the road and in camp, let things at least cool to ambient temperature or put them in a pan of cool water to cool them before putting them away.   Limit opening your fridge or ice chest.  Each time you open it you lose cold air and allow warm moist air in. Keep ice chests in the shade.  Make sure the cooling coils and vents on your RV fridge are clean and clear.  An extra fan can be installed to help move air across the cooling coils.   I like to use a solar-powered fan so it doesn't draw down the batteries.  Check the status of the burner on gas absorption refrigerators periodically to be sure it is not restricted by debris or insect or vermin infestations and that the flame is properly adjusted.  Don't over pack your RV fridge.  The air needs to be able to circulate to maintain proper cooling.   Avoid storing large containers that block air flow. Transfer large volumes of foods into multiple smaller containers for better performance and added convenience.  Air circulation is not as important in ice chests, but allowing room for ice between items is still a good idea.   Put large, flat packages on top so they don't restrict circulation and don't sit in ice melt and get soggy.

Most modern RV refrigerators are have electronic controls,  and all you have to do is select the right power source (gas, 120 volt AC, 12 volt DC).  In automatic mode, most refrigerators will operate on 120 volts whenever it is available and switch to gas when the shore power is unplugged or the generator shut down.  The 12 volt setting usually has to be manually selected.  Older models may need to be lit with a match or at least depress a "Push To Light" button.  Pressing the button allows a small amount of gas to flow to the burner to get it going.  Once it is going, the thermocouple  or sensor will open the gas valve to keep it going.  If you have an older fridge that has to be manually lit, follow the lighting instructions carefully to avoid accidents.  Holding the pilot button down too long before lighting the burner or not waiting long enough between tries a can result in a flash explosion that will easily remove your eyebrows and lashes and might set your hair or your RV on fire!

How cold is my fridge/ice chest?  There are special refrigerator thermometers available to measure the temperature.  A fridge should be kept at about 40°F to preserve perishable foods.  The mixture of ice and water in an ice chest will remain at exactly 32°F until all the ice has melted.   The air above the ice/water mix may be slightly warmer.  Don't drain off the ice melt until you need to lighten the chest to transport it.   Draining off the ice water just wastes some of the cooling resource.  The ice water will be at 32 degrees and can still absorb a lot heat from the things you put in the ice chest.  If you do have to dump the water because it is soaking the contents, dump it over another ice chest (or the same one) to cool the outside and help keep it cooler inside.  Waste not, want not!

Cleaning/defrosting.  Ice chests need only to be emptied and cleaned with a good household cleaner. I like to use a window cleaner with ammonia.   It cleans and disinfects the surface and helps prevent mold or mildew from forming.  Any good disinfecting cleaner will do.   Since most ice chests have white interiors, using a cleaner with some bleach in it can eliminate stains and help keep it looking new, but don't go overboard on chemical cleaners.  They can damage the plastic surface.  For really stubborn stains, try spraying them with WD-40 or use a "Magic Eraser" on them.  Leaving the lid or door slightly open during storage will deter growth of mold and mildew.  RV fridges require the same kind of cleaning periodically, but you will also need to defrost the freezer compartment.  Some modern fridges include a "frost free" options that reduces or eliminates frost build up, but you may choose to turn the feature off to conserve energy.   If you do get frost builidup during a trip you may need to defrost the fridge to maintain efficiency.  The end of each trip is a natural time to clean your fridge.   The best way to do this is to turn off the unit, open the doors, and let it defrost naturally. Scraping is a bad idea! It is too easy to damage the shelving and even puncture the cooling lines.  I've seen people use a heat gun or hair dryer to speed defrosting but I don't recommend it.  The heat can melt or warp plastic and even warp metal components.   If, in desperation, you do resort to using a heat source and damage the plastic, seal it with silicone caulk.   A safer technique to speed defrosting is to place bowl of warm -- not hot -- water in the compartment.  Avoid or reduce frost build up in the first place by limiting opening the freezer and wipe any moisture off any items before you put them in the freezer.   I pre-freeze my ice cube trays in my home fridge before each trip.  That reduces initial load on the RV fridge and the frozen trays won't spill.

Gas refrigerators require a proper flame to operate efficiently.  Yes,gas refrigerators are cooled by fire!  The flame should be blue and steady.  If it is not, it needs to be adjusted or the fuel supply may be faulty.  If the flame is yellow, flickers, or sooty, there is definitely a problem.  The only adjustment available to the owner is the collar that controls the air fuel mixture right on the burner.   It is usually secured by a single small screw that needs to be loosened so the collar can be turned to increase or decrease the air/fuel ratio.  If you can't achieve a proper flame by adjusting the collar, you have plenty of propane in the tank, and the main valve is fully opened, you may have to have a trained technician make repairs.  He/she will be able to check the gas pressure to ensure the regulator is working properly and that the lines and valves are clear and operating correctly.  Gas pressure should normally be 11" water column as measured by a manometer.  Since most of us don't have a manometer in our tool kits, this is best done by a qualified RV or propane appliance technician.

All refrigerators and powered coolers have cooling vents that need to be kept clean and free from any obstacles that might reduce air flow.  Dust and dirt or other debris may accumulate on the cooling coils on a gas refrigerator or the air flow may be blocked by insect or rodent nests or a damaged vent cover.  Check the vent and the coils periodically to make sure they aren't contaminated.  Use compressed air to blow the dust off the coils.  While you're at it, check the burner to make sure insects or rodents haven't take up residence there too.  Take care where you put your portable powered cooler and avoid blocking its vents. You can add 12-volt or solar-powered fans to aid in moving air past the cooling coils to improve the performance and efficiency of your RV refrigerator.  Most RV refrigerators have a roof vent that aids in creating a chimney effect to help exhaust hot air from the coils.   Design limitations sometimes force top and bottom side vents, which are typically not as affective.  Adding an auxiliary cooling fan can often mitigate problems with side-vented refrigerators.  The most convenient solar powered kits have the solar panel built in to a new roof vent cap.  Solar kits are 3-4 times as expensive as 12-volt direct wire fans, but they won't run your battery down.  The only downside to solar fans is they won't get power at night, so if you live where you have very hot nights you may want to consider a direct wire fan instead or in addition to your solar fan.   Check both the amperage draw and the fan output (cubic feet per minute).  You want the highest output you can get and the lowest amperage draw.  If you have the need to replace a vent cover anyway, you might want to consider upgrading to a solar fan kit at that time.  That way you can apply the cost of the replacement vent cover toward the cost of the solar kit making it more affordable.  I've seen people adapted computer cooling fans to cool their RV fridges.  There are quite a large selection of fans at varying amperages and air movements to choose from.  The more powerful the fan, the better it will work, but the more amperage it will draw. 

Operating/usage tips.  First, limit opening your refrigerator or ice chest as much as possible.   Plan your retrieval or storage of items so you can do as much as possible in one opening.  Close the door/lid as quickly as possible.  Let cooked food items cool and wipe of any excess moisture before putting them in the fridge or freezer.  Take care not to over pack your RV fridge.  Internal air circulation is critical to proper operation.  The addition of a "Fridge Mate" battery powered fan that sits on a shelf can aid in circulation. You can usually get Fridge Mates at places like Camping World for around $20.  They run on 2 "D" cell batteries so you'll want to check the batteries regularly.  I have tried door guards but quite frankly didn't find them to improve things as much as simply limiting opening the doors.  These guards are made of flexible clear plastic in strips about 3" wide. You may have seen them on doors to walk-in refrigerators in supermarkets.  The idea is reduce to flow of cold air out and warm air in. Judicious opening of the door is usually sufficient and is more convenient and less costly than using a door guard.   I recently saw a fan kit that attaches to the fins in the refrigerator using Velcro and is wired into the interior light.   It draws a little power from the battery but moves a lot of air directly over the fins and greatly increase cooling efficiency.  As I recall, they are a little pricey, pushing $100, but they are more powerful than battery powered fans and you don't have to keep replacing the batteries.

Make sure any bottles or containers are tightly closed or sealed before you put them in your fridge or ice chest.  Normal vehicle motion will cause things to shift and may spill, wasting provisions and making a nasty mess to clean up when you reach your campsite.  Make sure the door on RV refrigerators is securely latched so contents don't spill out into the aisle on turns.  Take care when opening your fridge or ice chest when you arrive in camp. T hings are likely to have shifted around inside and may spill out when you open the door or lift the lid.  This is usually a more common problem with RV fridges than with ice chests.  Shifted contents inside an ice chest may shift further when the lid is opened, spilling inside the chest instead of out onto the floor.

Odors can be a problem in ice chests and RV refrigerators.  Your first defense is to avoid odors by properly packaging all foods before you put them in.  Over time, some odors are bound to accumulate.  A box of ordinary baking soda will absorb many odors and help keep your fridge smelling fresh.  It can be used in ice chests too, but be careful to keep it up out of the melt water. Proper cleaning of ice chests and refrigerators between uses will also help keep them smelling good. Just about any good household cleaner will do the job.   I prefer using a window cleaner with ammonia to freshen the unit and inhibit mold and mildew.  If you get odors while using your fridge or ice chest, first look for and discard any rotting food. Then clean up any residual ooze it may have left behind.  Use a box of baking soda to absorb errant odors.  Keep any foods with strong odors in tightly sealed containers.   You don't want your chocolate cake to absorb the odor of last night's cauliflower!

Cool it!