Went to carry out a service today. The people had only just moved in. The boiler was a 60,000 BTU/hr open flued Potterton Kingfisher II boiler. The original compartment vents had been plastered over and this imaginitive solution applied instead. I issued a warning notice and capped off the gas supply to the boiler with the customers permission. I have also Riddored it as the paperwork is loooking very dodgy.
This is the view that I got when I opened the cupboard
CQ9R0225 by
Mike Jackson1, on Flickr
The instructions showed the boiler needing 212 sq cm low and 106 high from outside. 110mm soil gives around 80 so looking bad to start with, too low even for the high level vent.
Looking up inside the cupboard revealed.
CQ9R0229 by
Mike Jackson1, on Flickr
So at least it's got high and low level but woefully inadequate.
I then noticed a wire coming from the longer section.
CQ9R0228 by
Mike Jackson1, on Flickr
Closer inspection revealed this to be an inline duct fan which clicked on when the burner ignited. Somehow the fan has been connected so that when the boiler stat calls for heat it turns on. It was obvious that there was no proving switch because the burner lit and I then heard the fan spin up to speed. I didn't manage to work out what the bit of pump screwed to the wall was for.
Checking in the roof space revealed the kopex connected to the fan running to a vent slate.
CQ9R0235 by
Mike Jackson1, on Flickr
Whilst closer inspection showed the other section connected to some rectangular ducting.
CQ9R0239 by
Mike Jackson1, on Flickr
CQ9R0237 by
Mike Jackson1, on Flickr
CQ9R0240 by
Mike Jackson1, on Flickr
Looking outside showed a very restricted inlet for the roof vent.
CQ9R0219 by
Mike Jackson1, on Flickr
The other vent was a bit better.
CQ9R0249 by
Mike Jackson1, on Flickr
All in all a very imaginative solution to the problem of the blocked compartment vents but with none of the necessary safeguards.