Gas pipe width to supply both boiler and gas cooker

[manicomio]

Hello,

I currently have a Worcester combi boiler installed in the kitchen. The gas piping is 22mm.

A GasSafe registered engineer came round to install a new gas cooker for me. However, he said that 22mm would not suffice and I would need to replace this with 28mm. Reason being that with 22mm, when I had both the cooker and the boiler on at the same time, the gas supply would not be constant (i.e. the gas supply to the cooker may cut out).

There is a pretty long run from the meter to the boiler. Underneath the floorboards of the living room, bedroom and then outside the house to the kitchen. So replacing the whole 22mm piping with 28mm is out of the question due to cost.

However, when I had my boiler serviced, the British Gas engineer told me that 22mm should be sufficient and you could just T-off the pipe in the kitchen supplying the boiler and use that to supply the cooker.

I have no other appliances in the flat using gas.

Any thoughts gratefully welcomed! Thank you.

 

[doitall]

Need information on the boiler make/model the size of the cooker, as well the total length and number of bends for the gas pipe.

From what you say so far I would certainly say the pipe needs upsizing to at least 28mm, in fact if the cooker cuts out then it's ID and a shut off job.

I'm surprised the RGI didn't.

 

[mysteryman]

The RGI should be capable of calculating this. He should not be guessing.

 

[manicomio]

Thanks for your replies so far.

The boiler is the Greenstar 24i Worcester Bosch.

The cooker is the Beko 50cm gas cooker (both hob and oven are gas, not dual fuel).

http://www.appliancesonline.co.uk/product/DVG592WP-Beko-Gas-Cooker-White-21279.aspx

The run of the gas pipe is pretty long - the pipe runs underneath the living room floorboards, which is around 2m long, then the bedroom so another 2m, then another couple of metres outside. There are a couple of bends in the pipe visible where it goes into the floor in the living room and outside into the kitchen, and possibly some underneath the floorboards.

He went round the flat and put some numbers in his head and then said I needed the 28mm. He definitely seemed to know what he was talking about - it's just what the British gas engineer said that made me confused as he was adamant that he had seen many flats with boiler and gas cooker using 22mm.

Though it is possibly the distance I guess from meter to the appliances that made the engineer say that initially.

 

[manicomio]

Need information on the boiler make/model the size of the cooker, as well the total length and number of bends for the gas pipe.

From what you say so far I would certainly say the pipe needs upsizing to at least 28mm, in fact if the cooker cuts out then it's ID and a shut off job.

I'm surprised the RGI didn't.

Sorry what do you mean by ID and a shut off job, and what are you surprised the RGI didn't do?

Thank you.

 

[doitall]

If the cooker goes out when the boiler fires up it is Immediately Dangerous (ID) and the gas should be turned off.

But it sounds like there could be another fault, really need a total length.

 

[Phill Peck]

Have you got the oven?
In the spec online it doesn't give a kw output, this should be on the databadge sometimes on the back or inside the door

 

[Dan Robinson]

If you want the appliances to work and not have the gas cut off then cost is irrelevant.

 

[manicomio]

Thanks for the replies.

I don't have the gas cooker currently installed - I currently have an electric cooker.

The engineer said in his opinion the cooker would go out (or there was risk that it would) if the gas supply was T-ed off the 22mm pipe that supplies the boiler.

Until I get the work done I wouldn't know if it actually did go out!

I was just confused as the British Gas engineer said he had seen lots of instances where a cooker and boiler share the same 22mm pipe.

Is it the case then that it is because the cooker and boiler are quite far away from the meter that the engineer thinks this?

I've just had a look at the plans for the flat - to get a pipe from the metre to where it supplies the boiler is minimum 20m. I remember him mentioning around 25-30m when he walked around trying to estimate it (without lifting the floorboards!). Would this necessitate an upgrade from the 22mm pipe?

Many thanks again for all your help, very much appreciated!

 

[Phill Peck]

Without seeing it its difficult but I would say probably yrs you will need most of it to be replaced in 28mm
Also without knowing the output or gas rate of your cooker makes it difficult but if both were on full it's gonna need a lot of gas.

 

[Dan Robinson]

Yes, but depending on the number of bends it MIGHT not have to be all the way.

 

[mickyg]

it would be cheaper to run another smaller pipe 22 or 15 along side the existing one back to the meter if cost is an issue.
If its 20+meters then he was right not to connect the cooker. Just because the BG engineer has seen something, does not mean its therefore ok ! He should of known better.

 

[kirkgas]

the BG man will have seen as many flats done like this as i have seen vans with bald tyres, doesnt make it right or safe

 

[ianmcd]

I would go with your origional engineers quote, its unlikely that he would quote you and lose the work, sorry to say it but most BG engineers havent a clue what they are talking about, you have to remember that BG are just another company the same as anyone else and most of their decent blokes have left and now work for themselves, have lost count of how many times I have forced BG engineers to call customers and apologise for getting it wrong

 

[dcawkwell]

If both your boiler and cooker were going full pelt
you could do it on about 9 metres of 22mm gas pipe.

Are your boiler and cooker going to be going full
pelt at the same time for long.

No. It will work.

To improve things you can replace the first part of the run with 28mm
gas pipe. It doesn't have to be the whole length.

Typical UK. Paranoia overdrive.