dvs_dave

Your’re overthinking the AC thing. Low refrigerant is almost certainly the problem. Just take it to your local kwikfit, or similar, for a 50 quid money back guarantee A/C service and you’ll be good.

Footwell heaters are electric and they burn out. Not much you can do other than replace them, or live with them not working. They’re only booster heat though so only used to get hot air flowing to rear footwell sooner.

Mike Freeman

Thanks - hoping its low freon. It's in for recharge on Wednesday. I've just never known a car with a freezing cold low side pipe, but no chilled air getting to the cabin.

I'd concluded the same with the foot heaters - thanks for confirming!

dvs_dave

A8 AC is a complex and advanced system that does all sorts of seemingly illogical things when it’s low on refrigerant. You will get led down numerous dead end rabbit holes with it when trying to apply traditional AC system knowhow. The hundreds of posts on this board over the years that conclude with a refrigerant charge solving all problems are testament to that.

Mike Freeman

You are of course - completely right, and a recharge resolved the issue

A very cool limousine it is now! Down to fixing some minor snags - but this thread is complete. Thanks again.