Run your air-conditioning once a week
That's the warning from warranty provider Warranty Direct, which says that air-con systems should be used at least once a week to prevent them needing expensive repairs.
Air-con systems typically use around 10% more fuel on average, depending on the type of vehicle. If left unused, parts can corrode or seize, and that can cost drivers dearly.
Warranty Direct says that the average repair bill for an air-conditioning system, which accounts for one in 20 of warranty failures, is £555.
As an example, replacing a condenser in a VW Golf will cost £620 for the part and around £140 for labour, and a replacement compressor will cost £380.
There are other hazards to leaving your air-conditioning off for long periods, too - there can be a build-up of bacteria, which multiply in a car's ventilation system when it isn't being used. This can affect asthma sufferers badly.
Annual maintenance checks can cost from around £40, which should give early warning of the problem and preventative repair. You can also use specialist bacterial cleaners from motor accessory shops to keep bacteria under control.