Combi conversion from back boiler (diagrams attached)

[stuartmorrell91]

Hi, Qualified as a plumber in 1994 and haven't really done much since but i have kept my hand in with my own house.

Just bought an old Victorian terrace and looking to convert the old back boiler into a combi in the kitchen. House requires complete referb so not worried about any mess. Now would one of you fella plumbers kindly advise that i have the following correct in my head?


From this drawing i Remove the old back boiler, cylinder, header tanks & pumps/valves.




Then as per this drawing, fit the new combi boiler on the kitchen wall, pick up the flow & return pipes to the rads, pick up the hot water pipe to the hot taps, then tee off the mains to the boiler, fit the room stats/timer and then re-route the gas (which i will have commisioned properly)




Apart from obvious steps of draining down and isolation, and a good powerflush before comission which of course i will do, have i missed anything obvious?

Any help appreciated.

 

[flameport]

Combi boiler also requires a condensate drain and PRV outlet.
You need to find some gas person before doing anything, as plenty will not want to be involved with a partly installed boiler or gas pipes fitted by others.

Is the back boiler beyond repair? Fitting a combi may not be the best option.

 

[gasmanstu72]

you need to separate the heating circuit from the hot water one, also the open vent and cold feed need to come away too.

 

[gas112]

Position the comb as close as possible to the main point of use tap so your not running loads of water away

 

[picasso]

Hope your ancient pipes and rads hold up to being pressurised.

 

[stuartmorrell91]

Thanks for your help so far.

To answer a few points, the back boiler is working ok but whilst I'm bashing the house I thought it would be a good idea to upgrade the heating system as I would be gutted if it failed once I've spent thousands doing the house up. I did look at the straight replacement back boiler but it's so expensive so a combi in the kitchen looked a better option, and I also need the airing cupboard space as i need to put a shower there, and the house has a loft conversion so no roof space. Most rads have been upgraded so I'm not too worried about leaks.

But if I did decide to upgrade. has anyone had any dealings with the new efficient modern back boiler? I think it's made by Baxi? It is an option and to keep the airing cupboard, any thoughts?

 

[gas112]

Dont get one they were not that good , think they have discontinued them

 

[stuartmorrell91]

Ok thanks I'll take your advice and stick to the original option of fitting a combi.

I might also take the advice of getting a Corgi guy in from day 1 to sort the gas out, at least then he's aware of what's being done to make it gas safe.

 

[kittedup]

Better go back in time to find a corgi guy pal

 

[Servotech]

Or even a ACOPS qualified engineer!