28mm gas pipe ugrade required for 35kw boiler ?

[gavm]

Hi i recently bought a broag remeha avanta 35c bolier and have just had a plumber round for a quote to install ..

He has advised i get a bigger gas supply pipe of 28mm from the meter to the boiler cupboard which i currently have 22mm pipework... The meter is approximately 10m from from where the current boiler is situated... Obviously this is going to involve more labour and materials with ripping up the floor etc to make good the upgrade..

He says i neeed a bigger supply because the boiler is a 35kw and also because im running a gas hob with single gas oven too...

Can someone please confirm this to be true or is the 22mm pipework i already have adequate to do the job as i had another quote from a heating engineer and he did not mention the pipe upgrade needing to be done...


Thanks in advance Gavin

 

[keighern]

depends on number of factures. Needs correct pipe sizing calculations doing to ensure sufficient flow of gas to appliances. To answer your question all installs are different so no definitive answer unless viewed and calculated.

 

[greemyamochop]

Maybe that the second engineer is not as good as your first but either way the only way to be sure is by doing correct calculations with the consumption required for all appliances.

When its worked out properly it may mean that only some of the pipework needs to be altered but i would say there is a decent possiblity it needs upgrading.

Mention it to the second engineer, if hes a decent installer hell do the calculations for you, i would if it meant getting the job!!

 

[Homesafe]

22mm at 10 mtrs with a hob and gas oven on might be OK but in winter say when the demand is high for heating and you are using both hob and oven with the heating on then the gas pressure is reduced to all appliances because it might not be sufficient for max usage.

That is what you have to work out the MAX usage of appliances and the the size / length of pipe will tell you what the pressure loss will be.

Undersized pipework can cause problems in your appliances and they can potentially become dangerous.

Your plumber could just put in a couple of lengths of 28mm from the meter to the 22mm and that should be OK but I'm going with what youve said, but then I'm not there.

 

[mickyg]

but 10m plus elbows/tees an oven and hob sounds like a 28mm jobby to me. Some modern 5 burner hobs are as much as 12kw, add your oven and your easily in 28mm territory.

if you can get your head around it, you can calculate it using this guide. you will need to know the "input"of each appliance being installed.

http://www.ukcopperboard.co.uk/lite...ion-Tips/Domestic-gas-planning-and-sizing.pdf

 

[gavm]

Thanks very much guys for all your input..

After reading your comments i am leaning towards the 28mm having to be used now.

Cheers Gavin

 

[Homesafe]

Good choice mate.

 

[Boilerman2]

unless the boiler is VERY close to the gas meter a 28mm supply will nearly always be required IMHO

 

[Happyplumber]

pipe sizeing is critical to any band A boiler so its good idea to do a proper calculation and make sure its the correct size


A big one will be better then a small one

 

[Boilerman2]

Thats what my missus says
signed Little John

 

[dreadnoughtheating]

And yet again (I say this to the regular CC guys answering this thread - you know who we are...) we have the customer supplying the appliance, and querying the technical knowledge of his installer..... should we as GasSafe installers presumably with a living to make, be answering any such queries?

Answer on a ping-pong ball please

DH

 

[ianniann]

should we as GasSafe installers presumably with a living to make, be answering any such queries?

No way! Meet in secret under a full moon, ban those NVQs that any fool can study for, and only let the first born son of seven generations of gas fitters apply to Gas Safe

 

[simond]

I don't think there is a problem with helping people with a question, whether it is gas related or not.

However I would question the wisdom of the OP buying the boiler and then trying to get someone to fit it.

Very few dedicated installers (eg: individuals/companies who specialize in boiler fitting) will entertain fitting a customer supplied boiler. I get calls regularly from people who are getting quite desparate having bought a boiler on the internet and can't find anyone prepared to fit it.

If you want to buy your own boiler I suggest you find an installer first - this might restrict you to a very small number of Gas Safe Registered contractors indeed. Certainly would take me out of the picture.

 

[johnjohnscg]

What should happen when a gassafe installer hasn't done the calcs as requested for a new install, then the customer's done their own and found the pipe to be undersized after installatio . Who's out of pocket for the upgrade pipe materials?

 

[picasso]

What should happen when a gassafe installer hasn't done the calcs as requested for a new install, then the customer's done their own and found the pipe to be undersized after installatio . Who's out of pocket for the upgrade pipe materials?

the installer will end up out of pocket, its the installers responability to ensure its done properly,you cannot blame the customer for not doing your job the way it should be done.