Length of gas pipe from meter to boiler

[mtuk100]

I have a domestic gas meter located at one side of my building and my boiler/cooker (only 2 gas devices) on the other side of the building. There is currently a 28mm gas pipe from meter to the boiler which is approx 25m and a further 5m to the gas cooker. My gas engineer is saying that the installation is non compliant (BS6891) and that I must get the meter moved to be close to the boiler which will cost a huge amount of money and I would need to dig a 25m channel through concrete and get Cadent to then move the meter. Is this correct? Is there another lower cost solution (eg: larger gas pipe?) Thanks for your advice.

 

[ShaunCorbs]

Did he state why it’s non compliant?

 

[mtuk100]

Did he state why it’s non compliant?

Just said that the distance from meter to boiler is too far. Something about pressure loss.

 

[Deleted member 120897]

Just said that the distance from meter to boiler is too far. Something about pressure loss.

Maybe get another opinion by someone who can pipe size? 35mm is probably the next size up, if that’s unsuitable then you’re probably looking at the meter, supply et al.

 

[ShaunCorbs]

Just said that the distance from meter to boiler is too far. Something about pressure loss.

Need to upgrade to either next size up eg 35mm or 42mm etc a gas engineer can work this out you may need a commercial one due to the size

 

[oz-plumber]

There may be a loophole for you.

I've done this a few times.

Test the suspect gas appliance operation / pressures while the appliance is running.
If the inlet gas pressures doesn't drop while the appliance is running, then you can deem that the gas pipe size / pressure is adequate.

You will have to make sure the boiler is rated at the expected kW output required.

eg: 24 kW boiler installed.
Heating required from boiler - 20 kW.

You make sure the gas burnt by the boiler equates to the 20 kW, not the 24kW

 

[Scott_D]

What kw is the boiler?
Is the cooker all gas or duel fuel?

 

[mtuk100]

What kw is the boiler?
Is the cooker all gas or duel fuel?

Vaillant Boiler is rated at 37kW and Cooker (4 burners plus oven) totals 30kW

 

[Timmy D]

There may be a loophole for you.

I've done this a few times.

Test the suspect gas appliance operation / pressures while the appliance is running.
If the inlet gas pressures doesn't drop while the appliance is running, then you can deem that the gas pipe size / pressure is adequate.

You will have to make sure the boiler is rated at the expected kW output required.

eg: 24 kW boiler installed.
Heating required from boiler - 20 kW.

You make sure the gas burnt by the boiler equates to the 20 kW, not the 24kW

You can’t have more than 1mb drop from meter to appliance.

You have to run the appliance at max, you can’t down rate it.

So I don’t understand what this “loop hole” is?

 

[Timmy D]

Vaillant Boiler is rated at 37kW and Cooker (4 burners plus oven) totals 30kW

EDIT: the calcs are wrong, had the app set to 25 feet, not meters.... pipe is too small.... Good catch Shaun.


It looks like you’re probably not much over, dependant on how many fittings have been used.

Roughly, 67kw at 25m and 14 high loss fittings comes out at 1mb drop in 28mm pipe.

Is there a gas test point under the boiler or did they test at the gas valve inside the boiler? If they tested at gas valve, it will add anywhere from 1mb-2mb on the reading.

If a reading from a test point under the boiler was 2.5mb, I’d agree but at the gas valve, I’d want to install a test point.

As above, I’d get someone else in who can pipe size and get a test point installed under the boiler.

Also, either way, because I think you’re pretty close to 1mb (depending of number of fittings), is there any exposed gas pipe? Or can you get to any relatively easily (under floor boards etc)? If so, a section could be ungraded to 35mm.

The whole pipe doesn’t need to be 35mm. It doesn’t even need to be the beginning section. Gas doesn’t care where the section is.

You also need to be careful not to upgrade the whole pipe (more than is needed) or the total volume will make it commercial. This is likely the reason the engineer told you to move the meter closer. I guess they don’t have a commercial ticket and don’t want to lose the business. Or they struggle with pipe sizing.

Out of interest, where in London are you?