How to Keep an RV Fridge Running While Driving?
We all like our food fresh and our beverages cold, especially when we are on the road. That’s why an RV fridge is a must-have item if you are planning a long journey. However, keeping your RV fridge running while driving long rides can be challenging for a plethora of reasons.
Whether or not you can leave your RV fridge on while driving depends on numerous factors that range from the model of RV you own or the power source the fridge uses to the type of terrain you’re driving through.
So, in this article, we are going to take a look at some of the ways to keep an RV fridge running while driving.
What is the difference between a household and RV fridges?
Assuming that an RV fridge is just like any other fridge is wrong. Household fridges utilize a vapor-compression refrigeration cooling method that utilizes a refrigerant, a compressor, and coils to keep a fridge cold. The compressor heats up the refrigerant before pushing it through the coils. As the refrigerant gets into contact with cold air, it starts to lose the heat, which reduces its molecular activity.
This causes the gas to turn into liquid. Moreover, the liquefied refrigerant enters the expansion valve where it is being depressurized. As the pressure decreases, the refrigerant becomes increasingly colder while going through the evaporator coils. After the refrigerant completes its journey through the evaporator coils, it turns back into the gaseous form and starts the same cycle again.
The vapor-compression refrigeration cooling method isn’t the most practical option for RV fridges since the compressor motor consumes a lot of energy and it has a lot of parts that can be easily damaged while your vehicle is in motion. That is the reason why the majority of RV fridges rely on the absorption refrigeration cooling method to produce low temperatures.
This cooling method is basically a series of chemical reactions between ammonia, hydrogen gas, and water. The process starts in the generator chamber, where the solution of water and ammonia is heated until the point ammonia turns into a gas. The newly formed gas is then sent through the condenser coils in order to release the heat and turn ammonia back to the liquid state.
The depressurized liquid ammonia then mixes with hydrogen while traveling through the evaporator coils. The mixture absorbs heat, which causes it to turn into a gas that cools the refrigerator, before reaching the absorber that contains water. The chemical reaction between water and ammonia releases the hydrogen gas that travels back to the evaporator coils where it is heated again.
The only major difference between household and RV fridges is the mechanical compressor since RV fridges don’t contain a mechanical compressor that can be easily damaged while driving.
Which power sources do RV fridges use?
We don’t usually associate heat with fridges. However, all types of fridges need heat in order to produce and maintain low temperatures. RV fridges use three different power sources:
- 120 AC
- 12V DC
Most RV fridge models can run on 120 AC and propane, which enables you to use generators or the electric grid at the campgrounds. Switching to propane tank while driving is an option, although if you decide to do so, you must take every precaution to prevent accidental gas leaks.
The so-called three-way RV fridges allow you to choose between 120 AC, propane and 12V DC power sources. RV fridges that can be powered from three different sources are much smaller than two-way RV fridges, and they are a more common option for pop up campers or small trailers.
Despite the fact that 12V DC heat source is by far the safest, it drains the RV’s battery quickly, which is the reason why most RV owners opt for two-way RV fridges that use 120 AC and propane power sources.
None of the sources of power RV fridges use are perfect since 120 AC power source requires you to have a battery that can generate enough power to keep the fridge running at all times.
On the other hand, it is prohibited by law to stop at a gas station while your propane-fueled fridge is on. Some RV fridge models can detect the available sources of power automatically and switch between propane and 120 AC when necessary.
Keeping an RV fridge cold while driving an RV
Your decision to leave the RV fridge on once you hit the road should be based on several factors, such as the duration of the journey or the availability of power sources. Let’s take a look at the different options you have at your disposal that will keep your RV fridge cold even during the long rides.
The dangers of driving with propane-powered RV fridge on
Driving while your propane-powered RV fridge is on, comes with a certain amount of risk. Most manufacturers recommend switching off the fridge while driving because hitting a pothole or making a sharp turn can push the propane tank out its proper position and cause gas leakage. Propane is a flammable gas, so even a tiny spark can trigger an explosion or start a fire.
To make matters worse, you can get a headache, feel dizzy, or even suffer a seizure if you inhale a significant amount of propane. That is why it is so important to keep your RV’s propane system in good condition and check if everything is connected properly.
Even so, you are required by law to switch off the propane while going through tunnels or if you are stopping at the fuel station. Using a propane RV fridge while you’re on the road comes with a high level of responsibility since even a minor accident can have disastrous effects.
So, if you think that the pros outweigh the cons of using a propane-powered fridge while driving, you can always keep your fridge cold. However, if you don’t want the extra responsibility, you should consider other sources of power that will keep your fridge running while you’re driving.
Using a generator to power a fridge while on the road
The majority of built-in or external generators can power a 120 AC fridge, but you’ll have to ensure that your gas tank is full before you start the journey. Most generators that draw fuel from your RV’s fuel supply are going to shut down automatically as soon as the fuel reserve drops below one-quarter of the tank’s full capacity.
This means that you are not going to be able to power your RV fridge until you refuel. In case you have a generator that uses propane instead of gas, you will have to follow the same protocols you have to follow when using propane-fueled RV fridge.
Moreover, bridges and roads can also have propane regulations. So, you must make sure that your propane-powered generator is switched off if you’re driving through an area where the use of propane is prohibited.
In addition, generators produce less power while an RV is in motion in order to limit fuel consumption and prevent accidents from happening. RV fridges need a lot of power to run, and some generators may not be capable of producing a sufficient amount of power to keep a fridge running while you’re driving.
Switch to 12V DC if possible
Three-way fridges have become rare in recent years, mostly because RVs and their fridges have gotten larger. 12V DC can generate only a limited amount of power that is insufficient to keep a modern RV fridge running over a prolonged period of time.
The RV’s engine recharges the batteries while you are driving, so the 12V DC won’t use up the batteries as quickly as it would if you were parked. However, if your fridge is constantly depleting your batteries, their lifespan is going to become much shorter, the same goes for your RV’s alternator.
The capacity of your RV batteries will diminish through time, and if you use them to power an appliance that consumes a lot of power, like a fridge, you will have to change the batteries more often.
Adding a second alternator is going to help you keep your RV’s power system in good shape if you want to use 12V DC to power your fridge on a constant basis. It is also advisable to pay attention to the weather since batteries last shorter on a hot day than they do when it is cold outside. Don’t rely too heavily on your batteries during the summer, because it can potentially damage them.
How to keep an RV fridge cold, even when it is turned off?
The distance you’re hoping to cover in one day should also play a role in your decision to keep your RV fridge running while driving. The fridge’s temperature shouldn’t increase for more than 4 degrees Fahrenheit over a six to eight hour period if it is fully operational.
However, you shouldn’t hit the road unprepared if you are planning on keeping your fridge turned off for the entire road trip. Here are the things you can do to keep your RV fridge cold before you begin traveling.
Turn down the temperature knob
Reduce the fridge’s temperature to the minimum a day or two before you start your journey. RV fridges may not be very efficient at generating low temperatures, but they are quite good at preserving the temperature. So if you turn the temperature knob all the way down, you’ll ensure that the fridge’s temperature is as low as it can be just before you switch it off.
Your food supplies shouldn’t go bad for at least ten hours after you turn off the fridge, which gives you enough time to reach a new destination where you can connect to the power grid and reduce its temperature again.
Pack everything at the same time
As soon as you turn down the temperature knob, you should start packing your food. Keep in mind that the bottom of the fridge remains cool longer than the top because hot air rises. So, place foods that can go bad easily to the fridge’s lower shelves and fruit or any canned products at the top.
Pack everything at the same time to ensure that both food and beverages have enough time to cool properly before you switch off the fridge.
Don’t open the fridge too often while you’re on the road
As we already mentioned, RV fridges are designed to preserve the same temperature for long periods of time. However, the temperature inside the fridge is going to rise quickly if you open the door frequently.
That’s why you need to plan ahead and keep all the food you need for the first few hours of the trip outside of the fridge, so you don’t have to open its door and increase its temperature in the process. Keeping the fridge’s door shut as much as you can also is advisable if you decide to drive while the fridge is on because it reduces the power consumption.
Ensure you have plenty of ice
Adding ice cubes and ice bags to the fridge’s freezer is going to help you maintain low temperatures for a longer period of time. The ice will melt eventually, so you need to make sure you have enough water containers in order to prevent the water from dripping all over your food supplies.
You should also keep in mind that it will take a while for the water to freeze after you switch the fridge back on at your next stop and plan accordingly to avoid any delays on your journey.
Stack your fridge with frozen foods
Fill any empty spaces between supplies you pack to the fridge with cold beverages to keep them cold for a longer period of time. Frozen foods can also help maintain low temperatures over an eight or ten-hour period, so consider stocking your freezer with foods that can be frozen easily.
Pack your fridge just below its maximum capacity and fill any gaps with frozen foods or cold drinks to maximize the amount of time the fridge can remain cold while you are on the road.
Maintenance tips that will help you keep your RV fridge cool while driving
Reducing the fridge’s temperature to the minimum before switching it off is just one way of keeping your fridge cold while driving. Proper maintenance can also help keep your fridge cool while it is turned off. Here are a few tips that can potentially increase the amount of time a fridge can stay cold.
Keep your RV fridge leveled at all times
Unlike household fridges, RV fridges don’t have mechanical pumps that ensure the refrigerant flows through the cooling system seamlessly. They rely on the force of gravity instead, which is the reason why you have to make sure your RV fridge is aligned with the ground at all times.
Even the slightest misalignment can slow down the flow of chemicals through the cooling system and cause the fridge to stop functioning properly.
If you’re driving with your fridge on, consider switching it off if you are climbing up a steep hillside or a mountain pass. Don’t park your RV on uneven terrain if possible, and add a bubble level onto the fridge in order to know if it is positioned correctly at all times.
Consider installing an RV fridge fan
Most RV fridges don’t have built-in fans, which mean that temperatures can differ from shelf to shelf. Installing a fridge fan can stop hot and cold spots from forming, and it can help you distribute cold air throughout the fridge more evenly.
The so-called ‘muffin’ fans are affordable, largely available, and virtually anyone can install them. They are commonly mounted at the back of a fridge, next to the evaporator coils, where they can help circulate the air more efficiently.
Installing two fridge fans is going to boost the airflow to the maximum, while significantly reducing power consumption. Fridge fans either use D batteries or 12V DC lines that power the fridge’s light as a power source, and they won’t increase the amount of fuel you’re spending to run your fridge while driving.
Frequently Asked Questions
Is driving while propane powered RV fridge is on a terrible idea?
Yes, it is because you can never really be sure if a sudden turn is going to jostle the propane tank and cause a gas leak. Even though it is not illegal to drive while your propane-fueled fridge is on, you must switch off your RV’s propane system when stopping at gas stations or while driving through tunnels.
How long can an RV fridge maintain a low temperature after I switch it off?
The temperature in your fridge will gradually decrease over a six to eight hour period. In ideal conditions, the fridge’s temperature will only increase for four degrees every six hours. However, installing a fridge fan and keeping the fridge’s door shut as much as you can help you maintain low temperatures for up to ten hours.
What is the safest way to power an RV fridge while driving?
The safest way to keep your fridge on while driving is to switch it to 12V DC power source. If you own a two-way RV fridge, then you should use a generator that can produce enough power to keep the fridge running.
Do I need to clean the outside of my RV fridge regularly?
The fridge’s vent has to be clean at all times because if there is anything blocking it, your fridge may stop w orking properly.
There are a lot of different ways to keep an RV fridge cold while driving. Choosing to leave your fridge on for the entire journey is going to put a lot of strain on your RV’s power system while leaving the propane-powered fridge on while driving can potentially be dangerous.
In case you are just planning a short journey, reducing a fridge’s temperature to the minimum before switching it off may be your safest option. Which method of keeping your fridge running while driving do you prefer? Leave a comment below and let us know.