The aircon in my car failed because I didn't use it enough - should it be repaired under warranty?

I've not been using the air con due to the weather conditions and now it doesn't work. I have a quote from my Nissan garage for a re-gas on my Qashqai at a cost of £159. I'm informed they need to re-gas the system to find out if there are any leaks and if there is a fault they will consider part payment under warranty. Is this a fair cost to charge a loyal customer?
This is a problem with a/c generally. It has to be used all year round to maintain the seals, otherwise the dry out. It is a particular problem with the current Qashqai because Nissan complied with an EU Directive to use R1234RF refrigerant instead of R134A. This new gas is more prone to damaging a/c systems, is more prone to leak, is flammable and costs five times as much as R134A. Not really Nissan's fault, though it has a greater problem over this than other manufacturers.
Answered by Honest John on

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