haven't had to do an air switch yet, but the one tip I would like to share mainly because it's very often overlooked and it's not on your list and that is the "thimble-like" sleeve filter fitted to the main water return junction on the boiler. Symptoms are:- slowly coming up to temperature/not reaching higher temperature, C.H. not circulating through all rads properly, diffuser not diffusing. Discovering this tiny filter is clogged alone could save an owner thousands of pounds potentially. Removed and cleaned in under 30 minutes depending how stubborn/accessible junction is. I believe a good boiler technician will know of this, and it ought to be the first place to look with above symptoms as it's so easy to rule out.
if you are eating, do not read on - today i have been mainly trying to talk to Hughie on around 5 occasions with no luck, nor will there be, as the "words" have now gone too far through the system. I put it down to dodgy coleslaw this time, stupid Chris, and at my age.
Impressive! Mine hiccuped at least once a year every autumn when I wanted the heating to burst -I would have welcomed limping- into life... The thought of another ten years of that BS, finally followed by replacement, which would likely mean the new owners would get most of the benefit!
