Air conditioning system failure is on the increase according to a report by Warranty Direct.

Eighty percent of new cars come fitted with air conditioning today, yet the likelihood of an expensive failure has jumped 55% over the past eighteen months.

The report says the most susceptible vehicles are those aged four years old.

Vehicles in months 48-60 of their life accounted for more than 44% of claims handled by the warranty specialist. The previous four years represented just 14% of claims.

The average repair bill is £444.68, making the air-con unit the fourth most expensive item to repair after the automatic gearbox, turbo and engine.

Although the air con units on some models look less reliable than others on paper, for example, the Volvo 850 reports a failure rate of 37% and the Ford Galaxy nearly 27% Warranty Direct is worried that too many motorists fail to see the importance of servicing.

“Too many people treat air con as a fit and forget option,” warns Warranty Direct’s Duncan McClure Fisher. “Units need regular use and regular servicing to help prevent expensive breakdowns.”

An annual health check and service should cost around £40 from an independent specialist.