A few years ago we were unfortunate enough to suffer a blocked pipe in the boiler recirculation system - our's is a gravity system but with a modern condensing boiler. After he'd cut out the blocked section of pipe and replaced it we had a devil of a job getting the system bled through again and had to close off some of the radiators to boost pressure and get the air pushed round. You've just reminded me I never balanced them again. Last year I did notice the radiator in the hall and one of the bedrooms was not getting fully up to the same temperature as the others. Hoping a rebalance will sort that, fingers crossed it's not a sign that there's still blockage problems!
Regarding servicing of gas appliances. Strikes me it's a bit of a cash cow for some companies? I'm very fortunate with our boiler man, who I think I've mentioned before? Needless to say he's fully Gas Safe registered but has also become a friend over the years. When he does my boiler not only does he remove the front and vacuums out the burner (not strictly necessary he tells me as long as it's burning cleanly) but he also cleans out the condensate trap which seems to accumulate a sort of sandy deposit. Then he checks for leaks and for burner efficiency and charges me "not a lot".
A few years ago we had a "hole in the wall" balanced flue gas fire fitted in the living room. The people who fitted it for us were quite pushy about trying to get us to sign up for an annual maintenance contract but I resisted. I asked our man if he could look after it and he said they don't actually need much maintenance as all they are is a burner, no fans etc, so he could stick his "sniffer" up it's exhaust each year and tell us if it wasn't burning cleanly and do a quick leak check on the roomside of the fire with his sniffer - He doesn't make any additional charge for this.
However last year I noticed the glass front was looking a bit cloudy inside so asked if he'd clean it for us. "A man with your skills could easily do that he said. Tell you what, take the front fascia off while I'm doing your boiler and call me through". This gets the fancy trim out of the way and reveals a rather obvious ring of 8 set screws which hold the glass bezel in place. So I undid them too and the bezel, glass and a thick woven soft seal all comes away very easily. Great he said, now try cleaning the glass with soapy water, which I did but some of the deposits were a bit stubborn so I deployed the Elbow Grease: https://elbowgreasecleans.com/ (if you haven't tried it you don't know what you're missing, honestly, I've cleaned engine blocks with it!) then washed it down with clean water and dried it. Then I took all the ceramic coals out and vacuumed the burner bar - I was surprised how much general cra* there was in there and relocated the coals (which was satisfying as the positioning of some has annoyed me since the fire was fitted) Refitting the glass was the reverse of dismantling but the glass was snugging up very nicely against the woven seal before the screws were even half tightened down, so I called my pal through and asked him if he thought I should tighten them down fully (as they had been) or leave them just nipped up on the seal - I was worried that the glass might break if the screws were fully tightened. He agreed with me but double checked the tightness for himself then fired it up and checked round the seal with his sniffer. Putting the fascia back on was just a couple of minutes work and he got me to fire it up while he finished doing the boiler. Then he nipped outside and stuck the sniffer up it's exhaust and declared all was good. Didn't even charge any extra for the fire checks. so from now on that's what we'll be doing, I'll give the fire it's cleanup while he attends to the boiler then he'll check the fire for combustion and leaks.
I thought I'd just check up on the tightness of those screws with the manufacturer so gave them a ring and was lucky enough to speak to one of their engineers. No, he said, don't tighten them down to the stop, you'll very likely crack the glass! Just nip them up so the seal is decently compressed. When it was installed the senior fitter left the fitting of the glass to his "boy" who used an electric screwdriver to tighten the screws right down as far as they could go. He didn't start the screws in their holes by hand but put them on the end of the screwdriver bit and zipped them in under full power. It was no surprise to me to find one screw cross threaded badly enough I had to run a tap down the hole and clean the screw thread up too and another was slightly "tight". probably the thread "pulled" a wee bit, it came good by winding it in and out a couple of times. Inexperienced fitters shouldn't be let loose with power tools until they are competent!
The point of all that above is to detail what my "proper" boiler man does. I've watched a couple of the neighbours boilers being "serviced" and I doubt if their boilers even had the front's taken off! the man was in and out far to quickly.
