Gas pipe sizing

[doitall]

I see your point but aren't pressure and flow two different things?

J

Yes they are, but they are also related.

The governor on the meter should be set at 21mbar, you have to get that pressure to the appliances give or take 1-2mbar, to do that you need to calculate the resistance in the length of pipe and the number of fittings, which is why you need the 28mm because the 22mm will be too small.

 

[Doctor Drivel]

Hello All,

I need to upgrade my gas supply pipe from 22mm to 28mm for approx 8 mtrs from the meter before reducing back to 22mm. If the first few inches of supply pipe from the meter are in 22mm would this cause a bottle neck restriction i.e. 22mm-->28mm-->22mm?

TIA J

No, it will make no difference the first few inches being 22mm.

I have found it does. On some installations where the pressure drop was a little too much, replacing the outlet with a 1" x 28mm bent connector and around 1 foot of 28mm solved it.

If he needs 28mm back to the meter say for half the run, then a restriction in the run with impact.

In a commercial installation yes, for an domestic it will make no difference.

The official capacity for an U6 is 6m3/hr.

3m of 22mm copper pipe will deliver 8.7m3/hr. How will increasing the size to 28mm improve the situation, when the potential capacity is already exceeded with the 22mm

I am speaking in general terms. In this instance it will not matter.

 

[Doctor Drivel]

I see your point but aren't pressure and flow two different things?

J

Yes they are, but they are also related.

The governor on the meter should be set at 21mbar, you have to get that pressure to the appliances give or take 1-2mbar, to do that you need to calculate the resistance in the length of pipe and the number of fittings, which is why you need the 28mm because the 22mm will be too small.

Each fitting and bend adds "length" to the pipe run. A 6 metre run full of elbows may be like a 15 metre straight run.

That is why I said adding a foot of 28mm to the meter outlet in some cases will get the 1 mbar drop from meter to appliance as it adds less resistance and in effect "shortens" the pipe run.

 

[Terrywookfit]

My god, why can't people just answer a simple question instead of constantly giving stupid comments?

Who said anything about doing it myself?

My comments were appropriate to a stupid question!!

Does your installer not know the answer??

Transco would only have 3/4" inlets yet the installer would have 28mm from the outlet. I recommend replacing the flex inlet with a 1" if possible. Available from http://www.bes.co.uk

The above statement proves your total lack of knowledge of the situation !!
You should not be giving advice on subjects that you have no understanding of!!
Stick to posting your googled knowledge of thermal stores!!

Can you explain where it is incorrect?

Could you explain the reasoning behind your recommendation to upgrade the Anoconda!!

 

[Doctor Drivel]

My god, why can't people just answer a simple question instead of constantly giving stupid comments?

Who said anything about doing it myself?

My comments were appropriate to a stupid question!!

Does your installer not know the answer??

Transco would only have 3/4" inlets yet the installer would have 28mm from the outlet. I recommend replacing the flex inlet with a 1" if possible. Available from http://www.bes.co.uk

The above statement proves your total lack of knowledge of the situation !!
You should not be giving advice on subjects that you have no understanding of!!
Stick to posting your googled knowledge of thermal stores!!

Can you explain where it is incorrect?

Could you explain the reasoning behind your recommendation to upgrade the Anoconda!!

I said..."Can you explain where it is incorrect?" So far you can't.

 

[Terrywookfit]

My god, why can't people just answer a simple question instead of constantly giving stupid comments?

Who said anything about doing it myself?

My comments were appropriate to a stupid question!!

Does your installer not know the answer??

Transco would only have 3/4" inlets yet the installer would have 28mm from the outlet. I recommend replacing the flex inlet with a 1" if possible. Available from http://www.bes.co.uk

The above statement proves your total lack of knowledge of the situation !!
You should not be giving advice on subjects that you have no understanding of!!
Stick to posting your googled knowledge of thermal stores!!

Can you explain where it is incorrect?

Could you explain the reasoning behind your recommendation to upgrade the Anoconda!!

I said..."Can you explain where it is incorrect?" So far you can't.

Your advice would have no effect on working pressure at meter outlet!!