Air Conditioner Basics: Power Requirements & Common Issues
Air conditioners are usually a 240V appliance and often the highest power draw in the van. Most “air con not working” issues are actually power supply or breaker related.
Fitment varies by model/year.
What the air conditioner needs to run
- Stable 240V shore power (caravan park / home outlet)
- RCD and breakers ON (including any dedicated air con breaker)
- Correct mode/settings on the controller (cool/heat/fan)
Fast troubleshooting (most common fixes)
- Confirm you are plugged into 240V and it’s live.
- Check internal switchboard: RCD ON, breakers ON.
- Check if the air con has a dedicated breaker and reset it (OFF then ON).
- Turn the unit OFF for 60 seconds, then ON again.
- Try a different mode (fan only) to confirm the controller works.
Common causes
- Low/unstable power supply at the site
- Breaker trip due to overload (kettle + microwave + air con, etc.)
- Incorrect mode (cool vs fan) or thermostat set too high/low
- Dirty filters reducing airflow (performance drops)
Filter care (simple maintenance)
- Check and clean filters regularly in dusty conditions.
- Reduced airflow can look like “not cooling”.
What to include in a support ticket
- Mars model + year
- Air con brand/model (photo if possible)
- Is it powering on at all? Any error code?
- Photo of 240V switchboard (RCD/breakers)
- Where you’re plugged in (park/home/generator)