New house high water pressure..

Soldato
Joined
29 Jun 2004
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2,559
Hi all.
Moved into a new House 90's build. Noticed in the bathroom the water pressure is so high out the bath tap both hot and cold the combi can't heat the hot on full flow. These taps also are dripping when off and so does the valve behind the toilet.
Mixer shower in the ensuite didn't work either as wasn't mixing in any cold now fixed.
Think I would be wise to install a pressure bar valve on the mains?
I get 12l a min at the kitchen tap but that's with aireators (sp) on the taps, so if they weren't there I'm sure the pressure would be way too high.
Any thoughts?
 
Soldato
Joined
13 Jun 2011
Posts
5,780
Got a watermeter outside? Turn the flow down a bit. The keys are normally left under one of the manholes, may need to open a few they are normally in a group unless your detached.

Easy fix.
 
Soldato
OP
Joined
29 Jun 2004
Posts
2,559
Got a watermeter outside? Turn the flow down a bit. The keys are normally left under one of the manholes, may need to open a few they are normally in a group unless your detached.

Easy fix.

Yes I have a water meter and it's a detached.
Would this solve the problem though fully as people on forums say this would just reduce flow rather than the pressure
 
Soldato
Joined
13 Jun 2011
Posts
5,780
Yes I have a water meter and it's a detached.
Would this solve the problem though fully as people on forums say this would just reduce flow rather than the pressure

Googling seems that you indeed right and i was wrong. But as its free to try id be interested to
See what happens anyway :) certainly wouldn't hurt anything
 
Last edited:
Associate
Joined
21 Jan 2008
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Location
Cotswolds
Hi all.
Moved into a new House 90's build. Noticed in the bathroom the water pressure is so high out the bath tap both hot and cold the combi can't heat the hot on full flow. These taps also are dripping when off and so does the valve behind the toilet.
Mixer shower in the ensuite didn't work either as wasn't mixing in any cold now fixed.
Think I would be wise to install a pressure bar valve on the mains?
I get 12l a min at the kitchen tap but that's with aireators (sp) on the taps, so if they weren't there I'm sure the pressure would be way too high.
Any thoughts?

Fix the leaking taps and toilet for starters. Are you in hard water?

Sounds more like the boiler is inadequate!
 
Permabanned
Joined
22 Jul 2020
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2,898
3 bar?

It is 6bar here (W.Scotland) and I am told it will be higher soon (about 7bar) by a few plumbers doing boiler installs in my area, my boiler (old now) states to limit the inlet cold water to bar and I have this via an adjustable pressure reducing valve.

I adjust my heat out hot taps but opening or closing the gate valve under the boiler so it speeds up or slows down the cold inlet water, ideally its to be 60C at full flow for bath water with little need to add much cold water and to feed shower.

Obviously this temperature varies depending on time of year as of the water ambient temperature hence just slow a turn the tap on less or more and for shower adjust from 7 to 8-9 on water temp control without need to touch the flow control which will be full.
 
Last edited:
Soldato
Joined
28 Oct 2002
Posts
3,328
fit a pressure reducer on the incoming pipe. we fitted one that reduced to 3 bar, which is still good pressure but in tolerance for all taps / appliances etc.
 
Soldato
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13 Apr 2013
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10,758
Location
La France
I thought water mains pressure is meant to be around 1-1.5 bar typically. 3 bar is high I'd have thought

That’s what I remember mine being in London. My mains pressure in rural SW France fluctuates between 7-11 bar depending if the neighbouring farms are taking water from the mains for crop irrigation.

Which is why I have a pressure regulating value on my side of the water meter.
 
Soldato
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16 Oct 2007
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7,332
Location
UK
That’s what I remember mine being in London. My mains pressure in rural SW France fluctuates between 7-11 bar depending if the neighbouring farms are taking water from the mains for crop irrigation.

Which is why I have a pressure regulating value on my side of the water meter.
I was under the impression domestic properties (in the UK) are designed for 5.5-7 bar max
 
Soldato
Joined
13 Jan 2003
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21,465
I was under the impression domestic properties (in the UK) are designed for 5.5-7 bar max

Probably.. but in theory the water company can provide anything from 0.7 to 7 bar IIRC.. varying over day/weeks etc.

Best is simply fit a pressure limiting valve, only issue is the filtering of the supply from debris that can block them.. still I'd fit one and worry about that at a later stage.
 
Associate
Joined
7 Jan 2007
Posts
744
First measure the incoming mains pressure at various times of day. It's most likely excessively high (especially overnight) which has damaged your taps.

If so, you need a Pressure Reducing Valve on the incoming main, set to 3 bar usually. Get one with an inline strainer which you can clean for maintenance.

The combi not heating the water adequately requires a flow restrictor. A gate valve can be used to achieve this, or if you have isolation valves on your taps, turn them down.

As said already - reducing flow does not reduce pressure. The two are quite different, but are related.
 
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