Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws

Install the app
How to install the app on iOS

Follow along with the video below to see how to install our site as a web app on your home screen.

Note: This feature may not be available in some browsers.

So, upped the pipework to 28 in basement, cut in a test point under the boiler and proved pipework was fine at 1mb drop.. still getting 12 working at meter. So I call NG. Guy says, don't run boiler on max rate, just run it normally because we don't test in max rate. Says if he gets good wp at meter at normal rate he's leaving. So I start to call gas safe register. He says run the boiler on max rate. He then finally accepts there's a problem with service pipework and calls it in!!!!!!

He reckons by running a boiler on max rate will generally always get lower than 19 wp at meter. Really? I say. I've never seen this before at the meter when I've done installs. Reckons that's how it is.

Jesus H Christ!!!!
 
  • Like
Reactions: 1 person
They do that with the huge output domestic boilers the manufacturers are selling now.
40kw combi,s, why?
 
Ok.. so back to the original job on this post..

I fitted a Vaillant 30kW system boiler and upped the pipework in 28mm from meter to boiler as boiler and hob wasn't getting enough gas

I've now added a test point to both boiler and hob. I've also teed the hob off the 28 which I brought further up underneath the boiler..

I added the test point on the 15mm.. so!

Standing @ meter 25mb
WP @ meter both app 21mb
WP @ meter 1 app 21.5mb
WP @ boiler test point 20mb
WP @ hob test point 20mb
WP @ boiler with hob on 19mb
WP @ hob with boiler on 19mb

Have told custard to replace hob as burners went out with just hob on- hob is 30 years old.

I expected to see a working pressure of 20 at both appliances when both on.

Pipework is not undersized.

Why am I only getting 19????

30066a0e763dc97d7fbb644b66373427.jpg


3ad66e255d22823d94e68acce94f49c3.jpg


These are my pipe calculations for what's currently there..

a463a0994b3335f88d0b4da92d9ef3cb.jpg


df91809d21cad3a3735cd921b67156b3.jpg
 
Last edited:

Official Sponsors of Plumbers Talk

Similar plumbing topics

We recommend City Plumbing Supplies, BES, and Plumbing Superstore for all plumbing supplies.