Width of piping needed?

[Mignonnette]

Hi, I'm looking to get my combi boiler replaced with a condensing boiler. The gas feed pipe looks to be 15mm wide, and I've been told by one person who quoted it must be replaced by 22mm pipe. The second person who quoted says it doesn't need replacing.

So which is correct? While I don't want corners cutting, I also don't want cost and hassle I don't need.

The only other gas appliance I have is the hob on my stove. It's a one bedroomed flat.

Many thanks for any advice.

 

[CBF]

it depends on the inlet pressure you have at the moment & what you need for the new boiler there are calcs that can be done which your RGI's should be doing based on boiler input, lenght of pipe runs, amount of elbows etc etc, plus most boilers req the size of gas pipe to be equal or greater than the gas connection size on the boiler

 

[gaswizzard]

Hi, I'm looking to get my combi boiler replaced with a condensing boiler. The gas feed pipe looks to be 15mm wide, and I've been told by one person who quoted it must be replaced by 22mm pipe. The second person who quoted says it doesn't need replacing.

So which is correct?.

Both 'could' be correct , if the boiler is further than 2 metres away from gas meter then i'd say the 1st person is correct , maybe the 2nd person noted that the gas meter was directly under the boiler in a kitchen base unit.