I noticed that my air con didn’t seem to be quite as effective as I thought it should. It could just have been my imagining things as the UK was bloody hot at the time, well, you know, by UK standards. It was either get the air con system re-gassed or put some new air filters in as they may have become blocked. A bit of googling and it seems the air filters should be changed every two years. The car is now five years old and I can almost guarantee they’ve never been done – so that was the first stop.
Order new air filters
Watch youTube video about how to replace air filters
Rip car apart and change filters

It wasn’t a particularly tricky job, but laying on your back across the door frame looking up underneath the steering wheel to remove some air vent ducting was a trifle uncomfortable.
Air filters replaced. No real noticeable difference in the air con but the UK has cooled down a bit now so no rush. I’ll probably start investigating re-gassing the system soon. Maybe it can wait until Spring – we’ll see