12V DC or 3-Way?
Here’s another question we get asked often. Abosrption (3-Way) or DC (12/24V)?
Even though there are 3 ways to power a fridge (LPG, 240V AC, 12/24/V DC), there are only 2 main types of low-power cooling systems, Absorption and Compressor.
These 2 types of cooling systems are very different, and this makes them suitable to different situations. Here we’ll briefly explain each type of cooling system and which situations they are best suited to, so you can make a more informed decision.
A Short-Cut To The Answer!
If you just want a short-cut to our advice, here it is. If you'd like to know more, then continue to read on past this paragraph.
Absorption Fridges perform their best when they are primarily operated on 240V or LPG in a stable and level situation, like in a houseboat, cabin or at your base camp. The benefit of an LPG fridge is you only need to invest in a bottle of gas and you are up and running for weeks or months at a time - so the up-front costs are minimal.
Compressor Fridges are the best all-rounders as they are suited to all environments. They will perform better in extremely hot and humid conditions or when a stable and level surface is not available, like in a 4WD, truck, caravan or boat. To run your compressor fridge, you will need a stable 12 V or 24 V power supply, mostly likely from a car battery or bank of batteries.
A compressor fridge uses electricity to run a low-power compressor, which in turn pumps the refrigerant through the cooling system.
Our DC fridges use Secop Danfoss compressors, which will run on 12 V or 24 V and are happy operating in a moving vehicle or on angles up to 30º. In general terms, a compressor fridge will also perform better in extremely hot and humid conditions.
This combination makes compressor fridges the first choice for 4WD's, trucks, boats, RV's, buses and caravans. The 12 V power is generally provided by a car battery or bank of batteries which can be charged in a variety of different ways. These include; your car or boat engine, solar panels, a petrol/diesel generator or a 240V smart charger if you are in a caravan park or moored at a marina.
An absorption fridge uses heat to move the refrigerant through the cooling system.
LPG is the most efficient way to run an absorption fridge, as the LPG can instantly produce a very hot flame.
240 V power will also cool an absorption fridge well, although the heating element needs to produce the same amount of heat as a gas flame, so it is not as efficient as on LPG.
12 V operation in an absorption fridge is often considered a holding mode only. The temperature of the fridge will remain steady, but the fridge will not have the power to cool down quickly. This occurs because the small 12 Volt heating element cannot produce the same amount of heat as a gas flame, so it uses alot of electricity trying to keep up. The XD70 is the only 3-way chest fridge we sell. Most of our customers use it for long stints in the one place - like setting up camp for a couple of weeks at a time or for a more permanent off-grid situation.
A stable, level surface is required to operate an absorption fridge in the most effective way. So a moving car, caravan, motorhome or boat is not an ideal situation. For all mobile refrigeration needs, we strongly recommend considering a DC compressor fridge.
2-Way and 3-Way are terms referring to absorption fridges which can operate on 2 or 3 different power supplies. This is usually a combination of LPG and 240 volt (2-way) or LPG, 12 volt and 240 volt (3-way).
DC compressor fridges are generally the best for portable and mobile situations or when a stable surface in not available. The up-front costs are higher; batteries and either solar panels, a generator, or a smart charger. But after that you are up and running for years.
Absorption fridges are used mostly on LPG or 240 V and in a stable situation. They have a very low up-front cost (just a bottle of gas) and you do not need any AC or DC power for them to operate. Many of our customers will cool their XD70 3-Way fridge down on 240 V before they leave home, choose not to run it in the car, and then set it up on a bottle of gas when they get to their destination.
We hope this article helps you understand the main differences between absorption and compressor cooling systems, and which type of fridge is best suited to your needs.
If you have any other queries or would like some more information about our fridges, please feel free contact us anytime.