How often should I have my car's air con serviced?

I have the air con of my Toyota Auris 1.6 diesel permanently switched on and set to air recirculating in all weathers. I was wondering when the air con system will and how often require maintenance? The car is 4 months old and has done 6000 miles.
If you use the a/c like this it is self-maintaining because the lubricants are suspended in the refrigerant. You probably won't need a re-gas for 6 - 8 years. I recently had one done at 8 years and, because the a/c had been used regularly all year round, it had barely lost any gas.
Answered by Honest John on

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