Loss of Pressure from Gas Box to Boiler

[bahamasteve]

Hi,

I recently was informed by my plumber that there was a loss of pressure between the gas box and that at the boiler (some 15 meters away) and that I had to have new pipes fitted between the two. British Gas came out and also advised this. The existing pipes in the house are the smaller (9mm I think). Should these be the larger 15mm ones internally and would installing these solve the pressure problem? I would have thought smaller pipes would give greater pressure?...or is it a volume of gas thing...hence larger 15mm pipes are needed? We have used the existing 9mm quite happily for 7 years now with no problems but as we are renting out the property I am advised that this needs to be sorted or we wont get our gas certificate renewed? Is this correct? Is this something that would warrant not issuing a certificate?

I was concerned we had a leak of gas but I checked this by switching off all gas to the property (just the boiler) and left the gas meter for an hour...the digital meter did not move (so I think/hope we don't have a leak).

Grateful if anyone can shed some light on the above.

Thanks very much.

Steve

 

[Al-Glasgow]

The 9mm you refer to is probably the heating pipes and not the gas supply.

Check the size of the gas supply pipe leaving the meter.

The only way to check for gas leaks is with the proper equipment, not turning off the appliance control valve.

Al

 

[gas4you]

Hopefully you will have 22mm copper from the gas meter and not 15mm.

 

[chrishutt]

You're out of your depth on this one. Take professional advice and have the work done professionally. As a Landlord you have legal responsibilities to ensure the gas installation is safe.

The pressure drop from gas meter to any gas appliance shouldn't in theory be more than 1 mbar, though 2 or 3 mbar wouldn't matter much in practice. Bigger pipes allow the gas to flow more slowly with less pressure drop. The correct size can only be determined taking into account all the details of the installation.