inlet working pressure drop between meter and boiler

[poodelek]

Hello everyone


I wonder if anyone could help me get some answers…
Last year I had a new boiler installed. Before I had an old fashion boiler (installed in the lounge) so most of the system had to be replaced. Pipes run from the meter to a junction giving one branch to a cooker and one to boiler. I think that only pipe after this junction (pipe going to the boiler) was replaced by plumber fitting new system.
Last week I had an gas engineer for boiler inspection. He found that boiler inlet working pressure at high rate is only 15mbar whilst outlet pressure from the meter is 20mbar.
He suggested that there is a problem with pipework between meter and boiler, probably undersized pipe. I checked the system and it looks like there is 22mm all the way except narrowing in few joints. I also noticed that pipe is narrowed to 15mm directly before it enters the boiler. Please see pictures uploaded. Would 15mm pipe on few elbows/joints cause such a big pressure drop or could it be something else? It does not look like the system was flashed at installation or inhibitor was added but I wonder if this could be a reason.
I have no idea about plumbing and gas systems and I dont want my plumber to take an advantage of it.
Please advise

 

[joni os]

Nothing to do with flushing or inhibitor, all down to gas pipe size. Readings on site," trump " theoretical calcs. Readings indicate his instrument is within calibration limits and pipework needs sorting. Take his advice.

 

[ShaunCorbs]

I'm more worried about the state of your gas pipe work

Gas cooker flex connecting to hob and boiler, reducing wrong way (pipe sizing )

time to get a different gas safe engy in me thinks

 

[poodelek]

I'm more worried about the state of your gas pipe work

Gas cooker flex connecting to hob and boiler, reducing wrong way (pipe sizing )

time to get a different gas safe engy in me thinks

Thanks for your reply
Does it mean it should be 22m equal tee brass? Is it likely that pressure drops right there?

 

[poodelek]

thanks

 

[poodelek]

Nothing to do with flushing or inhibitor, all down to gas pipe size. Readings on site," trump " theoretical calcs. Readings indicate his instrument is within calibration limits and pipework needs sorting. Take his advice.

thanks for you reply. Im sure he's right. He only said somewhere between meter and boiler. I want to know if that junction could be responsible for the problem or its likely to be something else

 

[ShaunCorbs]

Thanks for your reply
Does it mean it should be 22m equal tee brass? Is it likely that pressure drops right there?

Should come from the meter/ nearest 22mm pipe if it can cope

 

[Frog67]

Looking at your picture I'd say that its not only undersized but also illegal.

 

[ShaunCorbs]

Looking at your picture I'd say that its not only undersized but also illegal.

Yes who ever fitted the hob also is naughty

 

[poodelek]

Should come from the meter/ nearest 22mm pipe if it can cope

not sure if I get it right. Does it mean inlet to tee brass should be 22mm? The pipe from meter to that point is 22mm all the way. Sorry if Im a pain but, as I said, I have no experience in plumbing at all. thanks