DIY Doctor

Gas pipe-pressure-renderingcorrosion-confused !

Postby Brian » Mon Apr 06, 2009 1:26 pm

I am your typical Joe Public, I can read about gas boilers and systems etc and then ask the Gassaferegister listed person to come and look and give me a quote for the work required. It is ME that pays the bill.
Installer A looks at the gas feed pipe from meter to boiler-10m distance-with take off for gas hob, and says that the present 15mm copper pipe will not do because it won't carry enough gas pressure and will need a 22mm pipe.
Installer B looks at same pipe and says that the concrete rendering over the Victorian brickwork that uses the 15mm copper pipe as an edge/finish line, about 8 inches above ground level, will not do as rendering corrodes the copper and will not get signed off. Rendering has been there for 20 yrs.

A said nothing about this rendering and B said nothing about gas pressure.

This Joe Public is now confused by the comments/non-comments of two registered, qualified installers.
Are they both correct , but missed a bit or what !!!???

Comments please.


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Simply Build It

Postby htg engineer » Mon Apr 06, 2009 4:47 pm

They are both correct.

Maybe installer A didn't mention the rendering because - as he says the 15mm pipe is no good, and would have to be upgraded to 22mm - so the 15mm pipe will not be used and if it corrodes it wont matter.

Maybe B has said he cannot leave the pipe in because the rendering will corrode the pipe, if you said ok replace it - he may have said ok i'll replace it in 22mm ?

Really you will have to ask them - but they are both right, unprotected pipework will corrode and 15mm pipework is no good to feed a boiler and a gas cooker - 22mm would be the minimum size - 28mm if a longer run.

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Postby Steve the gas » Tue Apr 07, 2009 4:53 am

Steve the gas
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