gas feed to boiler

[im]

looking at the fitting instructions for my new boiler i see the gas feed should be 22mm is this critical? the existing boiler has 15mm pipe and getting a new feed there is going to be a lorra lorra work and ive got more enjoyable things to do. any help appreciated

breeze

[Owain]

Could be.

The pipe size required depends on the gas consumption of the boiler, and the length and number of bends in the pipe.

Are you replacing a standard boiler with a combi? Combis can have significantly greater gas consumption for the instantaneous hot water.

Owain

[John Rumm]

The gas rate required by the boiler, and the effective length of the pipe run will dictate the answer. For a smallish boiler close to the meter 15mm may be enough, for a powerful combi or a long pipe run you may even need some part of it in 28mm

Have a look here for details of how to calculate the pipe size required:

you want an exmaple of how to apply it, see this recent thread:

[Lobster]

Apart from what others have already said, ISTR from a previous thread here that it could be a safety issue under certain circumstances if the boiler should become starved of gas?

Loads of stuff on this in the ng archives - try googling.

Also. try this gas pipe size calculator:

David

[im]

thanks for the replies im off to get some 22mm copper

breeze