Gas Pipe size questions

[Yanni]

I bought a house last year and discovered the boiler is a 2015 Ideal Logic + 30KW Combi that has it gas feed on a 15mm pipe.
The distance between the gas metre and the boiler is around 1.3m pipe run, possibly less as it is installed adjacent to the wall of the gas meter.
There are 3 elbows on the pipe run. The first 300mm ( double wall plus cavity ) are on 22mm pipe with a T that is reduced to 15mm for the rest of the distance and another 2 elbows. So the full length of the 15mm is a bit less than a metre.

As I am refurbishing the kitchen should I upgrade to a 22mm pipe as otherwise I will have to rip some floor units in order to have access if there is a need for a bigger size pipe in the future.

 

[denso13]

Don't think I'd bother, it is close to the meter and I presume you won't need any more than 30Kw even if you change it.

But, if it bothers you....

 

[CountryFan]

If it was pipe sized correctly at the time and there's no issue, then I'd say it's fine, but if you wanted belt and braces, maybe go for it?

 

[gas112]

if its still under warranty then ideal may refuse to work on it as the pipework allowing for the tee will just be undersized
but nothing that will really effect it .
But if everything is accessible at present then get it changed to 22mm to future proof it so no one can say its not adequate for future boiler change

 

[muggles]

I would upgrade to future-proof in case you decide you wanted a more powerful boiler in future

 

[Madrab]

No reason not to if it's all accessible, always better over than under and, as suggested, if needed for any future requirements.

 

[fixitflav]

I bought a house last year and discovered the boiler is a 2015 Ideal Logic + 30KW Combi that has it gas feed on a 15mm pipe.
The distance between the gas metre and the boiler is around 1.3m pipe run, possibly less as it is installed adjacent to the wall of the gas meter.
There are 3 elbows on the pipe run. The first 300mm ( double wall plus cavity ) are on 22mm pipe with a T that is reduced to 15mm for the rest of the distance and another 2 elbows. So the full length of the 15mm is a bit less than a metre.

Allowable pressure loss between meter and boiler is 1mb. Calculated loss is well below that so no problem.

 

[gas112]

edit

 

[gas112]

Allowable pressure loss between meter and boiler is 1mb. Calculated loss is well below that so no problem.

33 .7 kw gross on 1 metre 15mm with two 15mm elbows is a drop of 0.8881 before allowing for how may exit the tee which could possibly take it well over

 

[fixitflav]

33 .7 kw gross on 1 metre 15mm with two 15mm elbows is a drop of 0.8881 before allowing for how may exit the tee which could possibly take it well over

Using 33.7kW, giving gas flow 3.1m3/h, 1m pipe, ID 13.6mm and generous roughness 0.02mm and 2 elbows I make loss just under 0.5mb. Online calculator I have says 0.68mb.
I don't think there's a problem, but if the OP is worried he could take some measurements.

 

[gas112]

Using 33.7kW, giving gas flow 3.1m3/h, 1m pipe, ID 13.6mm and generous roughness 0.02mm and 2 elbows I make loss just under 0.5mb. Online calculator I have says 0.68mb.
I don't think there's a problem, but if the OP is worried he could take some measurements.

use the proper pipe sizing calculators
1m meter of 15mm copper pipe is 0.49 its self
15MM elbow is classed as 0.4 of a metre so x 2 that is 0.8 of a meter so another 0.3947
So your calcs are well out
Then possible allowance for the tee

The figures of the logic plus 30 is 3.135m3 /33.733kw gross
https://gasengineersoftware.co.uk/resources/gas-pipe-sizing-calculator/

https://www.gb-gas.co.uk/NaturalGasCopperPipesizingChart.pdf

 

[fixitflav]

1m meter of 15mm copper pipe is 0.49 its self

Online calculators will have some safety added (understandably), but I've calculated it accurately.
Your figures are for elbows, mitred, but when did you last see one of those? They will be bends, I used the sharpest, r/d = 1, with loss 0.35 x vel pressure (mitred elbows 1.5 x). So online still gives more loss than me, but not as much. One gives 0.2mb for the two, I make it ~ 0.1mb.
Online gives total 0.69mb

So however you cut it, it's still well within the 1mb figure.

 

[Razor900]

Online calculators will have some safety added (understandably), but I've calculated it accurately.
Your figures are for elbows, mitred, but when did you last see one of those? They will be bends, I used the sharpest, r/d = 1, with loss 0.35 x vel pressure (mitred elbows 1.5 x). So online still gives more loss than me, but not as much. One gives 0.2mb for the two, I make it ~ 0.1mb.
Online gives total 0.69mb

So however you cut it, it's still well within the 1mb figure.

Yes because the fitter most definitely reamed all the pipes out and there is definitely no sulphidation build up internally.

If the boiler is due a service ask the fitter in advance to upgrade the pipe whilst they are there. For the sake of an extra £100 or thereabouts it's cheap insurance

 

[gas112]

Online calculators will have some safety added (understandably), but I've calculated it accurately.
Your figures are for elbows, mitred, but when did you last see one of those? They will be bends, I used the sharpest, r/d = 1, with loss 0.35 x vel pressure (mitred elbows 1.5 x). So online still gives more loss than me, but not as much. One gives 0.2mb for the two, I make it ~ 0.1mb.
Online gives total 0.69mb

So however you cut it, it's still well within the 1mb figure.

what the fek is a mitred elbow no the figures are for standard 90 degree elbows that are bought off the shelf in every shop/merchants that everyone uses
I have gave you two charts to work off that do not have any lea way added for safety so stop talking shyte and accept that you are wrong by every industry standard... The old saying you can lead a horse to water but cant make it drink adds up here as you sound like the sort that rides those horses ...Yep a cowboy.
Amuse me do you even know figures if a tee is involved and in what way?