Combi Boiler / Venting

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Mad Inventor™
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Just had BG in to service the boiler and got the cert AOK. It's a Valiant combi:

PC060005.jpg


Originally the house had a cold water storage and header tank in the loft with pipes running down into the airing cupboard where the combi now lives. The boiler vent goes straight up through the ceiling to outside.

PC060004.jpg


BUT where the old pipes came through are a couple of unsightly gaps:

PC060003.jpg


PC060001.jpg


The thing is that through these gaps it's blowing a gale. The insulation generally is a bit suspect throughout. The house, mid terrace is circa 1860. If I lay plastic dust upstairs sheets then a few hours later they've "inflated". The air gets in through the various air bricks etc.

Anyway, back to the airing cupboard, my plan was to simply cut the unwanted pipes back a tad then fill the gaps with some intumescent foam and cut it off flush. Will that "upset" the venting of the boiler? I assume it needs air intake but will it get enough from under the airing cupboard door etc. Or should I put a neat louvre vent in the door?

Cheers

 
All modern boilers are room sealed and "suck" air in through the flue. If you look at the flue from the outside you'll see that it's a pipe within a pipe, the exhaust in the central one and the intake between that and the outside one. They do not need to be in a vented cupboard or room (older non room sealed boilers excepted)

 
Nozspark is correct, but check your paper work as some boilers still say to be in a ventilated area. Also from next year all joints in the flue have to be accessible.

I can see something that BG have missed and against the Gas Safe & Valiant rules. The electric supply has to be from a double pole switch or an unswitched socket. Even though the double socket  may be  double pole, plumbers dont know how  ( and shouldn't be touching the wiring anyhow) to check that. Although the plug could be pulled out most don't, they just switch off,  so that should have failed  the test & be noted on the paperwok.  

 
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Nozspark is correct, but check your paper work as some boilers still say to be in a ventilated area. Also from next year all joints in the flue have to be accessible.

I can see something that BG have missed and against the Gas Safe & Valiant rules. The electric supply has to be from a double pole switch or an unswitched socket. Even though the double socket  may be  double pole, plumbers dont know how  ( and shouldn't be touching the wiring anyhow) to check that. Although the plug could be pulled out most don't, they just switch off,  so that should have failed  the test & be noted on the paperwok.  
Cheers for that. I have to address the whole area anyway. It's all now surface mount from what was the original, flush box that had a 1G for the immersion. Was thinking on the lines of a flush set, dual+1 back box for the 2G with a switched 13A DP FCU with flex outlet next to it for the boiler with the fuse dropped down. Not sure what's in that box with the blanking plate on yet. Then, Another flush set back box to mount the Siemens RF controller on etc with all the wiring hidden. It's all a bit nasty at present, he controller wiring for instance:

Photo0235.jpg


He didn't pick up on the 2G socket being cracked and having burn marks either though the fact I've scrawled "REPLACE" across the top in permanent red marker might have had something to do with it. He mentioned no visible main equipotential bonding. Though all pipework is at the same potential (long lead method) so far the only connection I've found is to the water, just below the stopcock in the same airing cupboard. I suspect the supplementary bonds are "helping" with the good readings. At first I thought they had cut the wire off the Tenby on the water, but it's their albeit buried under years of dirt. 

Before:

SAM_2883.jpg


After a bit of digging and hoovering:

PC060018.jpg


That'll teach me to be looking for something with insulation on! 

SAM_2861.jpg


 
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If that stopcock is the water feed the bond should be made above on the consumers side. The earth connection on the incomer looks DIY ?
It will be. I'm running a new bond from gas to water and back to the block by the CU. The incomer, I thought it looked soldered on but somebody else reckoned possibly a "lead" / "sweated" joint. I have BG coming in soon anyway to fit an REC isolator (what a difference in attitude from EDF) so will enquire then. I'll try and get a better shot meantime.

Extract from the gas cert, says "room sealed":

bg.jpg


As you say, electrical connections from Valiant manual:

valiant.jpg


 
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