Stanton premier plus -poor water pressure

[scanii]

I'm wondering if anyone can help. We have moved to a 3 storey 8year old home in which there is a Stanton Premier Plus unvented system.

Our problems are:
1. if you turn on one tap then try another you seem to totally loose pressure to a dribble/no flow at all. This is particularly frustrating with 3 toilets/bathrooms and having a family to get out of the house in the morning as you can't have more than one person in a shower at a time. Our old Victorian house and combi boiler managed better than this.

2. I thought hot and cold pressure was equal on a mains driven pressure system. The hot is ok until you turn on the cold and then the cold water pressure and volume seems to take over.

3. Water comes firing out for the first few seconds then slows- tends to soak people washing their hands as it fires out of the sink! (Does the same in bath on top floor)

Things I have found that may help diagnose our problem:
Water flow at kitchen sink 8L/min (!)
Pressure under sink at dishwasher connection 3 bar
Water pipe in 25mm then smaller (?15mm copper)
All stop cocks I can find are open
(Having said this we found the outside tap didn't work as some piece of plumbing was in backwards and the previous owners didn't seem to have noticed)
We have a water meter under the sink above the mains pipe entry
Showers are thermostatic
Taps are a variety of mixers and separate hot/cold but problems on all of them

Any ideas/solutions/further investigations would be much appreciated.
Thank you

 

[Agile]

Do you mean cold tap is 8 li/min open pipe?

That implies the cold supply is very restricted into the house if its low at the garden tap too.

The mains stopcock(s) may not be turned on fully?

After that its quite a job to identify where the problem lies and involves disconnecting pipes and measuring the flow rates at different places.

Tony

 

[scanii]

Hi Tony,

Thanks for your reply.
The kitchen tap is where I did the reading with all other appliances and taps off. The meter seems to be the only thing before that tap as far as I can tell.

The outdoor tap did nothing but we found a valve had been placed the wrong way around and that solved the problem. The pressure on that seems ok and the pressure on the top floor is fine with nothing else on and initially the jet of water out is very powerful out if a tap and the shower pressure when on on its own is also fine.

It seems the pressure isn't maintained across the system or after the first few seconds. That and what seems to be a poor flow rate despite the pressure.

 

[scanii]

And I checked the mains stop cock- it's as open as I can get it.

 

[Agile]

You have still not confirmed if it is the COLD tap you are measuring at.

I also ask if the flow at the garden tap is similar 8 li/min.

As I stated you seem to have a restriction on the mains supply into the house!

Tony

 

[scanii]

Sorry Tony, it was the cold tap and I have just done the outside tap- 8.5L/min. I'm measuring it the primitive way- stop watch and bucket.

Severn Trent say they guarantee a pressure not a flow on their website. The pressure seems to be adequate though I suppose perhaps the pipe could have been kinked or crushed perhaps on the way into the house perhaps?

Do you think I should contact them or is there a way of measuring flow off the main before the stop cock and water meter?

Thank you
Claire

 

[Agile]

A static pressure of 3 bar is pretty good.

Unfortunately, finding the restriction means disconnecting pipes and measuring flow rates at different positions.

Usual order is to check all valves on the supply are fully open first.

Then measure flow at first possible position when supply enters house.

What follows depends on what flow rate is found.

Nothing wrong with measuring with a bucket. It is far more accurate than using a Weir gauge.

Tony

 

[scanii]

Thank you