Campervan fridges explained

The fridge is usually the biggest single power draw in a van, which makes it the decision the rest of your electrical system has to be built around. Choose well and it hums away quietly off the battery for years. Choose badly and you are either replacing it or nursing a flat leisure battery.

We fit fridges into vans for a living, so this guide is the advice we give customers, not manufacturer marketing. It walks through the two cooling technologies, the drawer-versus-upright question, sizing, power draw, and the one ventilation mistake we see again and again.

There are two ways a campervan fridge makes cold, and they behave completely differently.

Compressor fridges use the same technology as the fridge in your house: a compressor pumps refrigerant around a sealed circuit. They run on 12V off your leisure battery, they are efficient, and they hold temperature reliably whatever the weather and whether the van is level or parked on a slope.

Absorption fridges (often called 3-way fridges) make cold using heat, from gas, mains electricity or 12V. They have no moving parts, so they are silent. But they have three real weaknesses: they struggle to hold temperature in hot weather, they need to be close to level to work properly, and on 12V they are extremely inefficient.

For a modern van conversion the answer is almost always a compressor fridge. Absorption still has a place in some motorhomes with a permanent gas supply, but for a self-build that parks in varied spots, in British and warmer European summers, a compressor fridge is the correct choice. It is what we fit.

Once you have settled on a compressor fridge, the body format is next.

Upright fridges have a front door, like a small home fridge. They are usually cheaper, simple to source, and give good usable volume. The catch is the door: in a narrow van the door swing eats into the walkway, and you have to plan the cabinet so it does not foul anything.

Drawer fridges pull straight out like a kitchen drawer. They cost more, but in a narrow van the format is genuinely better: nothing swings into the walkway, you see the whole contents from above, and you can put a worktop, hob or sink directly on top. They suit a fitted kitchen pod.

There is no universal answer here. An upright is the value choice and works well in a larger van. A drawer is the space-efficient choice for a tight build with a fitted kitchen.

Fridge capacity is quoted in litres, but watch two things.

First, the quoted figure is sometimes the gross volume, not the usable space. A fridge sold as "50L" may give around 44L usable once you account for the freezer compartment and the internal structure. Check the usable figure.

Second, bigger is not automatically better. A larger fridge costs more and draws more power, and it takes cabinet space and payload you might want elsewhere. Match the size to how you travel: a couple doing weekends needs far less than a family living in the van full-time. For most two-person weekend-and-holiday builds, somewhere in the 40 to 55 litre range is the sweet spot. Long-term or family use pushes you toward 90 litres and up.

This is the part that catches people out. A compressor fridge is the biggest steady load in most builds, so it has to be designed into your electrical system, not added as an afterthought.

Fridges are rated by average current draw over 24 hours, quoted in amp-hours (Ah). A small 12V compressor fridge might average somewhere around 25 Ah per 24 hours; a large 90-litre unit can average closer to 27 Ah per 24 hours, and both figures climb in hot weather, when the fridge is full, and when it is opened often.

The practical rule: take the fridge's quoted 24-hour Ah figure, treat it as a minimum, and size your leisure battery and solar around it with headroom for hot days. The fridge should never be the reason your battery goes flat overnight.

A compressor fridge does not just make cold, it sheds heat, from the condenser at the back. That heat has to go somewhere. If you box the fridge into an airtight cabinet, the heat has nowhere to go, the fridge works harder, draws more power and runs warmer. In a worst case it never reaches temperature on a hot day.

Every compressor fridge has a specified minimum vent area, an inlet low down and an outlet high up, so cool air is drawn in and warm air escapes. The single most common self-build fridge mistake is undersizing or skipping these vents. Follow the manufacturer's spec. It matters more than almost anything else in the install.

• Ventilation: build in the specified inlet and outlet vents. Non-negotiable.
• Power: wire to the leisure circuit on correctly gauged, fused cable. Undersized cable causes voltage drop and poor performance.
• Securing: a fridge is heavy and must be mechanically fixed into the cabinet, not just sat in place. It has to stay put when the van is moving.
• Levelling: less critical for a compressor fridge than an absorption one, but the cabinet should still be square.

We sell two compressor fridges, chosen to cover the two ends of the sensible range:

• Dometic Waeco WCR50 — the value choice. A proper 44L compressor fridge for smaller builds, in an upright format. The sensible way into compressor cooling without gambling on an unbranded marketplace fridge.
• Thetford T1090E — the premium choice. An 84L built-in compressor fridge with a curved back, designed for a fitted kitchen pod in a larger van. Drops into the same install aperture as the older T2095E it replaces.

Both are compressor fridges, because for a modern build that is the right technology.

• Product: Dometic Waeco WCR50 compressor fridge
• Product: Thetford T1090E 84L compressor fridge
• Range: Full compressor fridges range — Dometic NRX, larger Waecos and portable coolboxes
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