15mm or 25mm water connection and meter?

[Dreadnaught]

There's something slightly puzzling about my water-connection quote from the local water company.

 

The connection and the meter are specified as only 15mm, see below.

 

Is that normal? Should I ask for 25mm? I will be installing a 22mm communication pipe down my 40m access road.

 

[Russell griffiths]

Edit your post @Dreadnaught, I think you meant 32mm not 22mm. 

[Mr Punter]

They tend to fit a meter smaller than your connection as they are more accurate.  If you want a larger meter they may up your standing charge.

[Temp]

Personally I'd go for a 25mm meter and I'd want all the pipework from the main to the house in similar. It wouldn't be hard to persuade me to install a 32mm pipe but then we prefer quite high flow rate showers. Our internal plumbing is 28mm copper to manifolds then 22mm branches to the showers and 15mm via pressure reducers to basins. 

 

Since moving in 12 years ago we've also noticed the mains pressure reduce. We get a lot of burst water mains in the area, typically 1-2 a year (possibly due the use of asbestos cement pipes and clay soil) and it seems every time that happens the water co nudge the water pressure down a little bit. 

 

 

 

 

 

[Conor]

The meter size is different from the pipe size. They are a screw in type and the size refers to the aperture of the meter inlet - they are volumetric meters and that's the size of the "piston". A QN15 meter will have more than enough of a flow rate. This is most likely what they'll install:

https://www.bes.co.uk/elster-v210-manifold-cold-water-meter-20887/?ref=gs&gclid=Cj0KCQjw9b_4BRCMARIsADMUIyrPhohVX2wW1nmtA8L3ftTB-hIIvB6-AJQoX2eg2uiJ_KpB-Ib0IDIaAreuEALw_wcB

 

It's the only sized meter we'd ever install on a 25mm or 32mm service. The pressure loss is minimal and the more important factor is the diameter and length of the service pipe. You should install 32mm pipe all the way to your internal stopcock.

 

[Nickfromwales]

On 17/07/2020 at 06:39, Conor said:

The meter size is different from the pipe size. They are a screw in type and the size refers to the aperture of the meter inlet - they are volumetric meters and that's the size of the "piston". A QN15 meter will have more than enough of a flow rate. This is most likely what they'll install:

https://www.bes.co.uk/elster-v210-manifold-cold-water-meter-20887/?ref=gs&gclid=Cj0KCQjw9b_4BRCMARIsADMUIyrPhohVX2wW1nmtA8L3ftTB-hIIvB6-AJQoX2eg2uiJ_KpB-Ib0IDIaAreuEALw_wcB

 

It's the only sized meter we'd ever install on a 25mm or 32mm service. The pressure loss is minimal and the more important factor is the diameter and length of the service pipe. You should install 32mm pipe all the way to your internal stopcock.

 

+1.

Most mains around here are from a 3/8" tapping, but the flow rates are ridiculous. The flow rate at the street needs to be preserved, so you only need to fit larger pipe than normal if the distance that the water is to be conveyed is abnormally long. At 40m I doubt that there is much need to go to 32mm, unless the pressure and flow at the street is ?. However, I would never be an advocate of fitting less than 32mm because of the point @Temp makes, and that is that you are not guaranteed to still be receiving the same supply static & dynamic flow rates as first deemed. Putting in a bigger pipe now, uplift in cost of doing this would be the same as a pint and a kebab, is good insurance.

 

 

 

NOTE : Not all kebabs are equal.