How Do RV & Camper Fridges Work? (Explained For Beginners)

When I was first researching campers, I wanted to know why refrigerators cost so much more money than a refrigerator for your home.

I found out that it was because a camper fridge works differently than a regular fridge.

How does a camper fridge work?

A camper fridge often uses a combination of propane or electricity so that it can run in a variety of different situations.  A typical camper or motorhome fridge will not use a compressor as a standard home fridge does.

A camper fridge is usually much more expensive than a fridge you’d buy for your home.

For new camper owner’s this can be especially confusing because camper refrigerators are not very large.

The basics of how a camper fridge work

Ironically, a camper fridge works by using a power source to heat up the fridge.  Within the fridge, you find a combination of water, ammonia, and hydrogen gas.

The combination of these chemical compounds causes evaporation, which then, in turn, cools the refrigerator.

Most camper refrigerators can run off either propane or electricity. 

This is great because it gives the camper’s owner the opportunity to use their fridge while they are traveling or while they are parked somewhere without access to electricity.  Once the RV is taken to a place with electricity, the camper can then turn off their propane and run the fridge off of shore power.

In most cases, this is done automatically.

The camper’s fridge will run off of electricity while it is plugged in and will automatically switch over to propane after the electricity has been disconnected.

Some camper refrigerators do not run off of propane but use electric only.

However, these fridges are usually set to run off 12-volt batteries and can consume quite a lot of power.

When you operate it on 12V it draws a lot of energy (remember it has to heat a heating element – a giant resistor). With a single 100Ah battery, it will drain it to 50% in about 4 hours.

It certainly draws less VOLTAGE at 12v, but to compensate for lower voltage, it has to pull a lot more current (amps).

These camper refrigerators are great for people using solar power to run their fridge.

If you ever look at DIY van builds, you’ll notice that a lot of them use Dometic 12 volt fridges in their tiny kitchens.  This eliminates the need for them to carry propane with them and allows them to run their fridge off a house battery that is charged when the vehicle is running or from a small solar setup attached to the roof of their van.

Camper Fridge Options

• Propane/Electric Combination
• 12-volt/Electric Combination
• Mini-Fridge

When looking for a camper fridge, you’ll have three options to choose from.

All of these options have plusses and minuses, so it’s up to you to decide what fridge works best for your particular lifestyle.  One thought to keep in mind is that refrigerators tend to break down quickly when not in use.

If you only go camping with your camper a few times a year, you may want to skip buying a camper refrigerator altogether.

Propane/Electric Combination Refrigerators

The first option is a traditional camper fridge.  This fridge runs off of propane and electricity.  The great aspect of this fridge is that its ability to use multiple fuel sources makes it very versatile.

However, this fridge can be expensive to buy or repair.  Also, it must remain level while it is running.

If the fridge is left in an unlevel position for too long, it will get too hot and it will destroy itself.

The self-destruction of an older propane fridge can actually be dangerous.  Old propane/electric combination refrigerators can cause fires if left in an unlevel position while running.

Here are some examples of propane and electric refrigerators:

1) Norcold 2-Way Refrigerator without Ice Maker 5.5 – This fridge has a 5.5 cubic feet capacity and opens just like a smaller version of a home fridge.  It automatically changes between gas and electric and automatically ignites the propane flame when needed.  It usually sells between $900.00 – $1,000.00

2) Dometic New Generation RM3762 – 2 Way Refrigerator with Double Doors – This fridge has a large 7 cubic foot capacity.  It has several shelves in the refrigerator and two in the freezer.  The New Generation even has the ability to hold a one-gallon jug inside of it as well as half gallon jugs on the door.  This fridge sells for around $1,500.00.

12-Volt Refrigerators

A 12-volt/electric combination fridge runs off of 12-volt DC power and 120-volt AC power.  This means that the fridge can be run from a 12-volt battery as well as from a typical house outlet.

You’ll find that this fridge can cost even more than a propane/electric combination fridge, but it tends to be more durable.

Here are some examples of 12-volt/electric fridges:

1) The Dometic CoolFreeze CFX Portable Compressor Dual Zone Cooler and Freezer, 85L – This fridge is shaped like a cooler and opens from the top.  It can run off of 12 volt DC power, 24-volt DC power, and 120 volt AC power. It can hold up to 117 12-oz cans.  The CoolFreeze sells for over $1,300.00.

2) The Whynter 65 Quart Portable Fridge – This fridge also opens from the top and it can be run from a 110 volt AC outlet or from a 12-volt DC power source.  It has a 65-quart capacity and can hold up to 107 cans.  It sells for less than $600.00.

Mini Fridges

Some people opt to simply install a mini-fridge in their camper.

This is a much less expensive solution, but it can come with problems.  The reason for this is that these fridges have compressors and they are not built to withstand the constant movement of a camper.

Additionally, a mini-fridge will only run off of 120-volt AC power, so it’s not a great solution for those looking to go to places that do not have electric hookups.

One other problem with using a mini fridge as a camper fridge is that it has to remain level even when it is not running. 

This is because the coolant can pool up in one spot in the compressor.  Leveling the fridge out prevents this from happening.

Here are some examples of mini-fridges:

1) The Frigidaire – 3.3 Cu. Ft. Mini Fridge – This fridge is stainless steel and has a 3.3 cubic foot capacity.  It also has a small freezer at the top that can be used to make ice.  This fridge sells for around $100.00.

2) The Insignia 2.6 Cu. Ft. Mini Fridge – This fridge comes in black and it has a capacity of  2.6 cubic feet.  It also includes a small freezer at the top that can be used to make ice.  You can buy this fridge for less than $80.00.

Refrigerator Alternatives

There are only two real refrigerator alternatives:

1. The first one is a 12 volt DC cooler.
2. The only other fridge alternative is a standard cooler.

The 12 volt DC cooler

A 12-volt cooler is also known as a thermoelectric cooler.  This type of cooler runs off of 12-volt power, but cannot bring temperatures down as reliably as a true 12-volt refrigerator.

They can only bring the temperature down about 40 degrees less than the outside environment.

A typical temperature for a refrigerator is less than 40 degrees.  This means that a 12-volt cooler should only be used in temperatures below 80 degrees.

The up-side to this type of fridge is that it does not cost much to buy or operate.  It also has the ability to heat the interior up to 140 degrees Fahrenheit.  This is great for warming up leftovers, but not enough heat to properly cook food.

Electric Cooler Examples

1) The Knox Electric Cooler and Warmer – 48 Quart Capacity – This cooler can hold up to 60 cans and can run off of both 110 volt AC power as well as 12 volt DC power.  It has wheels built into it as well as a handle to pull it.  This cooler sells for less than $150.00.

2) The Cooluli Mini Fridge Cooler and Warmer – This is a small 4-liter cooler that can only hold 6 cans.  It can, however, run off of 12 volt DC power as well as 110 volt AC power.  It sells for less than $50.00

The standard cooler.

These can range dramatically in price based off of the time they are said to hold ice.  Unfortunately, none of them will hold ice for more than a week and they are all likely to make your food wet.

Also, there is an additional maintenance cost as you’ll need to buy ice to fill them with each time you use them.

Cooler Examples

1) The Yeti Tundra 45 Cooler – This cooler holds 26 cans and is said to be able to hold ice for up to a week in hot weather.  The price of this cooler is around $300.00.

2) The Coleman 70 Quart Extreme 5 – Day Heavy Duty Cooler – This cooler can hold up to 100 cans and is rated to keep ice for up to five days at temperatures up to 90 degrees Fahrenheit.  You can buy this cooler for less than $50.00

In Summary

Camper refrigerators work differently than standard home refrigerators.  They use a combination of chemicals rather than a compressor.

Most of them will run off of multiple power sources.  You’ll find ones that run off of propane and electric as well as ones that run off of both DC and AC power.

Using a mini-fridge from home is a bad idea because these fridges are not meant for travel and can break down quickly when left in an unlevel location.

There are a couple of refrigerator alternatives that may work for some campers, but they do not provide the same amount of cooling power as a standard fridge would.