Gas pipe sizing conundrum

[MarkAqua]

Went to look at a job yesterday which involves installing a new Worcester 30Cdi to replace an old myson.

The existing gas supply pipe to the boiler is 15mm from where the gas enters the building (it enters in 1" Steel)

Now here is my problem- the gas meter is some 90 Meters away from the building its a standard old ft/h diaphragm domestic meter. A 22mm pipe comes off the top to where it converts to 1" steel and then goes underground for 90m to the building, where it then rises externally 1m high and enters the buildings kitchen, supplies a commercial oven then a 15mm supply is tee'd in - this feeds the myson boiler.

How the hell do I even start to calculate if I can run supply from where it enters the building in 1" to feed a new boiler?

From where the gas enters the building to where the new boiler will be is 19m with limited bends.

Any advise would be really appreciated, my gut feeling is maybe a uprated meter? but will the 1" steel over 90m be enough?

Ideally we need a main supply right up to the building, but obviously that will have huge cost implications.

Cheers

Mark

 

[newcastle phill]

Unless you have an aecv where it enters. You may very well be outside igm/up/1b anyway for IV / purging etc

Sorry cant tell if your domestic or commercial

 

[MarkAqua]

Sorry mate, I work mainly commercial so have all qualifications

 

[newcastle phill]

Well looking at the steel lookup tables I have that go upto 50m

50m of 1inch (25mm) steel can manage 3.6 m3 per hour.

So 90m is gonna be considerably less.

Will you get the gas rate needed for boiler also allowing for other appliances ??

Nope

 

[Ermintrude]

Raise pressure to 75mbar !

 

[Ermintrude]

Or pull in a 65mm mdpe

 

[wattsie1987]

Entire re run required me thinks.

 

[Chalked]

New meter, fitted 90m closer to the building.?

 

[MarkAqua]

I'm thinking this is what they're going to have to do! nightmare!

 

[Reg Man]

50m of 25mm will only give you 2m3/hr. You have to work out your maximum demand for all appliances and any likely extensions. Then you an work out your pipe size from the IGE UP/2 documents. It sounds like a commercial ticket is required for the gas installation pipe.