A 12 V compressor fridge is the best fit for a campervan: it keeps cooling hard even in hot weather, runs from the leisure battery and switches itself off before draining it. Choose one first on capacity and power draw, then make sure there is enough airflow around the compressor, because a poorly ventilated fridge uses more power and cools less well.
1. Go for a compressor fridge over a thermoelectric cool box as soon as your trips last longer than a weekend.
2. Read the power figure on the spec sheet together with its test conditions, ambient temperature included.
3. Leave at least 50 mm of air around the unit, as Dometic requires.
Compressor, absorption or thermoelectric
Dometic makes all three types and compares them on its electric coolers page. In its words, compressor coolers are very powerful and deliver excellent cooling even in extremely high ambient temperatures, and can freeze regardless of the ambient temperature. Thermoelectric coolers are lightweight and can also heat, but only cool to 20 °C below the surrounding air, so food has to go in already chilled. Absorption fridges run on gas, independently of electricity, with cooling that depends on the ambient temperature.
In a van at 35 °C in summer, that means a thermoelectric cool box will not get below 15 °C. A fridge cools without relying on the gap with the surrounding air.
Reading compressor fridge power figures
Power draw is the most important figure and the hardest to compare, because each maker measures it differently. Dometic quotes 0.98 Ah per hour at 12 V for its CFX3 35, measured at 32 °C ambient with 4 °C inside. Truma tests its Cooler range at 25 °C ambient and 4 °C inside. The CFX3 manual gives annual consumption in kWh instead.
Here is a worked example based on the Dometic figure, to redo with your own model’s sheet. The result reflects hot conditions: in cooler weather the compressor cycles less often.
| Step | Calculation | Result |
|---|---|---|
| Hourly draw (CFX3 35, 32 °C) | 0.98 Ah/h | 0.98 Ah |
| Over 24 hours | 0.98 × 24 | 23.52 Ah |
| In watt hours at 12 V | 23.52 Ah × 12 V | about 282 Wh |
That figure goes straight into your power budget: our guide to sizing a van battery bank shows how to add it to the rest of your appliances.
Compressor fridge size and layout
Vans use two layouts. A chest fridge opens from the top and sits on the floor or in a box. An upright fridge opens at the front and is built into the kitchen unit. The Dometic CRX 50, a built-in upright, offers 45 litres in total including a 4.4-litre freezer, with a rated current of 5 A at 12 V and a weight of 17 kg according to its manual. UK retailer Van Junkies listed the CRX-50 at £625 on 13 October 2026.
Truma publishes a table of minimum solar panel and battery sizes for each model in its Cooler range, measured at 25 °C ambient with a 4 °C set point.
| Truma Cooler | Capacity | Minimum solar | Minimum battery |
|---|---|---|---|
| C30 | 30 l | 50 W | 30 Ah |
| C44 | 43 l | 60 W | 35 Ah |
| C60 / C73 | 59 / 72 l | 65 W | 40 Ah |
| C105 | 104 l | 105 W | 65 Ah |
Those minimums cover the fridge alone. For the whole van, our guide to van solar power sizing runs the full calculation.
Battery protection and ambient temperature
A compressor fridge cuts out before it flattens the battery. The CRX 50 manual gives a cut-off at 10.4 V and a restart at 11.7 V on 12 V. The CFX3 range offers three protection levels, and Dometic recommends the medium or high setting on a starter battery and the low setting on a leisure battery. Engel quotes a variable draw of 0.54 to 2.35 A at 12 V for its MT45.
Ambient temperature sets limits too. The CRX 50 is designed for ambient temperatures between +16 °C and +43 °C, and the CFX3 manual notes that the lowest setting cannot be reached when it is above 32 °C outside. In a van parked in full sun, keep an eye on cabin temperature: shade and ventilation matter as much as the model you pick.
Fitting a compressor fridge: ventilation first
The compressor produces warm air that has to escape. The CRX 50 manual asks you to install the unit so that warm air can flow away upwards or to the sides, far enough from walls for air to circulate, never covering the vents, with around 50 mm of space above if air cannot move freely elsewhere. The CFX3 manual requires a minimum of 50 mm of ventilation on all four sides and rules out closed compartments.
Plan a low vent and a high vent in the cabinet to create a flow of air, and wire the compressor fridge on its own fused circuit, as shown in our campervan wiring diagram.
Your shortlist for a compressor fridge
| Use | Our advice |
|---|---|
| Weekends, one or two people | 30 to 40 litre chest fridge, free-standing and portable |
| Regular trips | Upright fridge of around 45 to 60 litres, built in and ventilated |
| Full-time living | Larger capacity with a freezer, solar and battery sizing redone |
The right compressor fridge is the one your battery and panels can run without you having to think about it. Start from the stated power draw, check how it was measured, and keep a margin for hot days.