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Plumberpro, Plumber
Category: Plumbing
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Experience:  Heating and plumbing answers. 20 years experience
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Low water pressure at most outlets. My house was built in 2003

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Low water pressure at most outlets. My house was built in 2003 by Barratt, it has 4 bathrooms, a utility room, downstairs wc and kitchen. Mains supply is via 22mm into the utility room whose cold tap always provides a great deal of pressure. The same at the adjacent wc hand basin. The kitchen tap is the next nearest and noiw has a much reduced flow. All other cold outlets to the bathrooms also have greatly reduced flow . I have bypassed the supply to the kitchen tap and back fed it via a hose from the powerful tap at the utility room's sink. This produces a good flow at all other outlets. I can see no othe stop cocks or valves or restricters in the utility room or kitchen. I can see the supply pipe going directly into the wall of the utility room after supplying sink, washing machine and wc. The pipe is in a straight line with the kitchen tap about 4mtrs away. I guess that it is routed under the tiled, concrete kitchen floor and that there is some sort of restriction there. There is no sign of any leak that could be causing a drop in pressure. Up until a couple of weeks ago everything seemed to be OK, the pressure was acceptable but now it drops quickly after the initial stored pressure in the pipe depletes. So before I dig up the kitchen floor is there anything else I could do?
Hi , are you sure that the taps are off the mains and not fed from a tank in the loft?
Customer: replied 2 years ago.

Yes. I have no loft as such. The house was built with the loft space as a room with en suite. It also includes an airing cupboard with Sadia megaflo 250lt tank. I can see no other storage for the cold taps. When I turn off the main stop cock the cold taps do not stop immediately but I can not see any storage tank.

OK , you have an invented system . there are a few things it could be .
The water board may have dropped the pressure to reduce leaks. Legally they only had to supply 1 bar and an invented system needs at least 3 bar.
The pressure reducing valve may have developed a fault .
The megaflo may have lost the pressure in the pressure vessel. Try this first. Your pressure vessel may be built in or external. Look for a large round steel ball . if there is none then it will be inside. If inside the recharge instructions will be on a label on the outside.
Customer: replied 2 years ago.

OK thanks

The pressure in the utility room is way above 1 bar.

Where could the pressure reducing valve be? that was my initial thought but I also that it would be visible and accessible.

I have a red tank in the airing cupboard which is about 20 cm tall which I believe is the expansion tabk for the central heating.

Is the megaflo also supplying the cold taps then? I thought that it was only hot water.

I understand the pressure build up inside it from the cold supply, idea, and the hot taps give a real high pressure output for a short time but then they drop which seems to be right.

There are two pipes going into the small roof space above the "attic room" from the airing cupboard but I have not had a good look up there believing that everything was below that and that those were presseure relief pipes. I will go now and check it out.

Hi . the pressure reducing valve is included in the stopcock or just after the stopcock.
The red vessel will be doing the heating. The/water ones are white or blue. If you can't see one of those then it will be an internal one . if you have the exact model of megaflo I can confirm this.
With an unvented hot water system , the cold would be off the mains as well to give a balanced system . the cold would branch off after the pressure reducing valve.
Customer: replied 2 years ago.


The pressure reducing valve must be OK as the pressure at the utility room sink is very high but the pressure for the kitchen sink and all bathrooms is low..

The Sadia Megaflo is a CL250

I cannot see any other tank in the roof space just the two pressure relief pipes leading towards the eaves.

I can see the cold feed branching out to the kitchen and I guess everything else after the main stop cock. The downstairs wc has good pressure.
This is a video on how to repressurise the megaflo.
Try this first. However the last time I had a fault like this it was the pressure reducing multi valve
Customer: replied 2 years ago.

"Pressure reducing multi valve" as in main stop cock?

I will try the repressurising the megaflo but if its not related to the cold taps its not going to make much difference is it? Do you have a valve like this? Or could you upload a photo ?

The pressure reducing valve effects the hot water and cold water as both branch off after this

Customer: replied 2 years ago.


sorry I lost you.

I viewed the photo and when I closed it iu was disconnected from the site.

I have a valve like that in the airing cupboard at the top of the house.

Its connected in the cold line

Yes it has a lever stopcock , a pressure reducing valve , a non return valve in one . it may have developed a fault . you may have a non pressure reduced branch to the kitchen , utility are, then up to this valve where it branches to hot and balanced cold outlets
Plumberpro and other Plumbing Specialists are ready to help you
Customer: replied 2 years ago.
I discovered from another forum that the device has a strainer which can/should be checked as a blockage there could be causing the problem. This I did to discover that the main spring was rusted through and broken due to water ingress to that are hence the greatly reduced flow. I purchased a replacement but it had significant size differences. I have managed to add couplings etc to get it all together and installed. I now have full pressure at all taps - a luxury. Thank you for your help.
Your welcome. All the best. Glad you got it Sorted.