The rubber seals on your air conditioning pipes don't last for ever, especially when you don't use it regularly. The seals dry up and the gas escapes leaving you with no air-con. It is possible to refill it DIY style using a can from Halfords or a similar motor factors.
It states in the manual that the air con must be used for at least 15 minutes
every week otherwise the rubber seals will perish and the gasses will escape,
no gas, no air con. Use it or lose it.
OK, I Lost It, What Now?
You have 2 options, DIY or get a professional to do it.
420g + 0mg is the figure I have been told but 0mg of oil must be a refill
measurement assuming that the gas has escaped and the oil is still in the system.
Get a Professional
Look online for a local garage that deals with AC. This way you know
the system has been drained and everything has been done properly.
Do It Yourself
Quite a few motor-factors sell bottled air-con gas, even Halfords so go buy gas.
Remove the front panels (guide found here). You can reach the port just by taking
the bonnet panel off but the tubes you get with the DIY kits are too short (Thanks Bob S).
With the panels removed, look into the left hand side hole.
You will see 2 fill points. The lower of the 2 is the low pressure fill point (thanks Snuz2 for the info).
Always read the instructions on the can in detail and ensure you follow each step.
Remember that DIY isn't ideal, the gas has escaped but the oil may still be there,
adding more gas/oil may cause problems with there being too much oil.
Just adding more gas may not work long term. The new gas may escape from
the same place as before. You must cure the leak before the gas will stay put.
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