Gas pressure problem

Postby aaliya » Wed May 30, 2012 6:28 pm


i hope someone can help here...

We have built a 2nd storey extension (like a large size loft conversion) and have installed a second boiler to supply about 7 radiators and hot water. We are at the stage where we have connected it all to the gas supply but unfortunately there is not enough/ almost zero pressure being delivered to he second floor and the boiler is simply not starting. The pressure falls all the way down to almost zero when the boiler tries to start. The current supply to which we are connecting is already supplying ground and first floor (about 10 radiators and hot water).

We are stuck and looking at options, do we/ can we:

1. tap into the gas source (before the meter) and (as has been recommended by a private contractor) "T Off" another supply pipe for the second floor? can we get into trouble doing it privately?

2. or do i need to get in ouch with the supplier to get it resolved..?

Would gratefully appreciate your help. i don't have too much faith in the boiler fitter so turning to experts here.

thanks so much

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Postby Atticus Finch » Thu May 31, 2012 2:32 pm

Do you live in the UK? If you do, you are not permitted to do any work on gas pipes or anything using gas unless you are qualified. That means being registered with Gas Safe Register.

The reason for the low pressure is that the gas pipes have not been correctly sized.
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Postby plumbbob » Thu May 31, 2012 2:37 pm

Can I point out that gas installations should only be attempted by Gas Safe registered engineers who will be able to install the appliance correctly.

Unless you are fully compliant with regulations, be able to calculate pipe diameters and lengths and have the specialist equipment to check for correct gas flow rates, test for leaks and examine flue gasses, you are potentially playing with fire (no pun intended). The results could be catastrophic and a long prison sentence could await.

By all means, do the wet pipework yourself, but please please, get a suitably qualified engineer to do the gas work and install the flue.

Incidentally, connections before a meter are illegal.
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Postby htg engineer » Sat Aug 11, 2012 7:34 am

Given the fact that you've come across this problem, it's obvious there were no calculations carried out to determine the existing supplies could cope with the extra demand, meaning the people carrying out the work aren't qualified and haven't got a clue what they're doing. You cannot tee in before the gas meter as this is the supplier/transporter side and you'd be prosecuted.
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