Volkswagen recommends that you should have your air conditioning system serviced every 2 years.
WHY IS IT IMPORTANT TO HAVE IT SERVICED?
Over time, the gas in the air-conditioning system can escape, causing the system to lose the ability to cool and demist the windscreen. It could also possibly result in damage to the system, which would require the parts to be replaced.
First of all we evacuate the system to remove old gas and oil. Next, we put the system under vacuum to eliminate any moisture trapped in the system or the dryer. Once stage one has been completed, we then refill the system with the required amount of refrigerant, oil, and UV dye. Should any future leaks occur, we add UV dye to the system so that leaks can be detected under a UV lamp.
In addition, we also use a purification system for the interior of the vehicle which kills bacteria and bad odours.