Low pressure

[scoop]

Could anybody tell me why a house has very low mains pressure, there are no signs of leaks anywhere in the property, when all isolation valves are closed you can still hear water in the pipe using a screwdriver to my ear ( if that makes sense). When the stopcock is off it all goes quiet, whick makes me think the leak is in the property. But not sign of water. Any ideas? ?

 

[tackleburger]

I doubt it's a leak. Don't confuse pressure with flow either. Most commonly the main into the hose is choked either at a half open valve or something or is lead and is maybe slightly crushed underground. Get the pressure checked with a proper gauge and the flow measured using a suitable container or a weir gauge and take it from there. I have seen 3 -4 bar of pressure and 7 litres perminute of flow due to the above reasons.

 

[scoop]

It looks like copper feed pipe, Sev Trent had fitted new plastic boundary tap. But what about the sound of flowing water in the pipes when no taps are turned on in the house?

 

[andyg0507]

are you sure its not just expansion& contraction noise from your pipes??

 

[scoop]

I'm sure. no noise from the hot pipes, just the cold

 

[andyg0507]

as said above, maybe a valve is shut slightly, go round all valves and check to see if they are all open.

let us know the outcome.

 

[scoop]

Already done that yesterday, boundary tap fully open, stopcock fully open, isolation valve to sink and washing machine fully open. but still very low pressure.

 

[andyg0507]

sometimes its possible to snap the inside of the spindles on valves, so when you open it fully your basically just turning the spindle, if this is the case one of the valves may be partially shut, thus creating low flow rates

 

[scoop]

Good idea, i'll start with the stopcock first.
Stay posted. . . . .lol

 

[Alanka]

If the house has a suspended floor, there could be a leak in one of the pipes underneath the floorboards, which would cause constant noise (until you shut off the main stopcock) and also lower the flow rate at taps. Also, you would not see any leaks in the house, because the water would be collecting on the footings and probably soaking away.

The recent freezing weather could have damaged the pipework or parted a joint under the floor.

 

[scoop]

Thanks for all the advice.
Old galvanised mains pipe looks like it has broke, lifted up the manhole cover and water running in the drains and coming out of brick sides. Just a simple job to dig up the drive and fit new mains. . .what fun.

 

[andyg0507]

dont quote me on this but surely thats the responsability of the water board?

 

[Dava811]

dont quote me on this but surely thats the responsability of the water board?

Believe it or not, you are responsible for all pipes leading into and in your property, at least in NORTHERN ireland you are.

 

[andyg0507]

is that still the case if its outside your boundry??

 

[Dava811]

is that still the case if its outside your boundry??

I think so, tho don't quote me on it, might be worth googling
___________________________________________________________
You are responsible for installing and maintaining the water pipes within the boundaries of your property. This includes water pipes inside your home and drainage and supply pipes outside your home, but still within your property boundary.
Because these pipes are privately owned, we do not have information about where they are within your property boundaries. You may also be responsible for pipe work that is not on your property. This is explained further under the heading “Shared supply pipes” in [DLMURL="http://www.ukplumbersforums.co.uk/water-pressure-low-pressure.aspx"]the causes of low pressure[/DLMURL].

 

[tackleburger]

More than a possibility I'd still expect to get decent flow though out of at least one tap even with a leak. Best thing to do is get the pressure and flow rate checked properly. If you turn the main off and don't hear the water, a plumber or you yourself, if you are up to it, can rig up a bib tap direct from the main checking flow and pressure. Then compare that to say the pressure at the washing machine valve and the flow at the kitchen tap. It will give you the answer!

 

[scoop]

I've been told that i can fit a new pipe with use of a "mole", but may need Severn Trent to attach it to the boundary tap. But as they have replaced the boundary tap with a new plastic fitting, if they have fitted a tial of plastic pipe to the boundary tap and then connected to the old steel pipe, could i not just remove the old pipe and connect the new pipe myself or is that only to be done by Severn Trent?