looks like I've got to spend a grand+ in the least pleasurable way conceivable… on a new boiler. I've been quoted around £1k for a 32kw Vailant boiler + £250 fitting… does that sound like a good price ? Its a pretty straight swap of boiler only, moving from side wall to backwall 30cm away.

sounds about right

Don't forget to apply for the government grant too. I think it's worth £400.

Good price that.

Combi I assume?

don't forget to take into account ever changing regs.

I **think** (and am happy to be correced, in fact I'd love to be corrected) but for e.g. pipe from meter to boiler must now be 22mm – however am not sure how regs work – ie they tend not to be retrospective – so if fitting a new boiler does that mean changing the meter connection ?????????????

A 32kw boiler would require 22mm pipe regardless

FM – cheers
OP – hope you don't mind the blag..

you in the trade ??

anyway- is the pipe size based on boiler capacity or is it based on that the new regs say 22mm

and is it from the meter to the boiler.

Also – if your house had a boiler in the kitchen (on 15mm pipe) and a gas fire in the living room on 15mm pipe does that mean if you wanted a new boiler you'd have to repipe both from meteer withh 22mm

I've just got back to work after going home to let the boiler man in. Surprisingly he has suggested that it'd be best for us to have a new boiler (at the moment we do have two old ones one for water and one for heating so he right).

he did mention that we'd need the gas pipe from the meter to the new boiler replacing with a 22mm one. He also mentioned regs about room thermostats and thermostatic valves on rads?

can be bigger than 22mm, in fact be surprised if it didn't need 28mm. Depends on length of run, resistance of fittings and the appliances that are connected to that gas pipe.

Find a guy who can actually size the pipe correctly (and just because they are registered don't assume they can do it). When I do my courses over 50% of the people on it haven't a clue how to size a gas pipe, or quite frankly the importance of getting it right.

Depends on the energy requirement of the appliances connected.

Most standard heating boilers will be run on 15mm, because that's all they need.

Combi boilers in general need between 2 and 4 times the amount of gas to run a full throttle, so need a bigger pipe.

As bear says, needs to be done properly, unlike in my house when we moved in, gggrrr!

Say you have a 32kw combi, plus a gas hob of maybe 9kw, then a 2.5kw gas fire.

That's a combined total of 43.5kw, which must be taken into account or they will starve and not run properly.

The boiler will need a 22mm pipe, I know because I've done a few, but the rest could need upgrading to suit. You might then need 28mm to branch off into 10/15mm for the hob, and 22mm for the boiler.

simples 😯

eeek, minefield as usual.. The boiler its replacing was new in the year the house was built, 2000… any idea if that means I'll have up to date regs for pipe size etc ? Also, is 32kw overkill ? 4 bed house, shower off the Combi, current one is pants, takes 1/2hour to dribble a half bath full.
ta

EDIT: Should I just ask Peaty all this next week at the talk @ sheffield uni ?

Quote sounds really cheap to me. Current regs require TRVs on rads, except one (controled by room stat). System would require flushing with correct agent and inhibitor added upon commissioning.Benchmark boiler for Part L (energy efficently) then register boiler. For £250 pounds can,t be done, if so i will give that man a job !!

I paid £1700 for a 30Kw Potterton boiler, digi thermostat and TRV's plus the re-flush/inhibitor, brickwork and associated external pipework in November. Sought 4 quotes and all came in at £1700 so £1250 sounds either a steal or suspiciously low?

32kw should be ok. 36 would be better, or even 42. You'd probably only need around 12-15kw for heat only. The rest is just for the hot water flow.
My personal preference is always an unvented cylinder if possible.
Gave you definately got a combi now? They weren't commonly fitted to new build back then.
Round our way, they're all gravity fed , crappy potterton suprima's

Hes done my neighbors 2 boilers (one house, one fish pond) so a good contact.

So, if you change the boiler, you have to bring the whole system up to current regs ?… so even if a boiler failed, and had to be replaced, the same have to happen ?

Yes, pretty sure its a Combi, e.g. it does heating and water on demand, no tank etc.