Low water pressure in 3rd floor flat

[alfier]

My daughter has low water pressure in her flat. We checked with Thames water and it's ok outside (so they say) but all the flats (converted from office building) have low water pressure.

The whole flat has been updated i.e. floor, bathroom and all the plumbing which replaced the copper with the PVC stuff.

I've just had a direct link from the mains input fitted to the flat feed but still same low pressure. see photos

Any ideas?

Alfie

 

[Gasguru]

Get a cheap pressure gauge and measure the static pressure in the flat ie the pressure with no taps running. Post back result.

 

[alfier]

ok if I can find one and figure out how to use it.

 

[jon26]

ok if I can find one and figure out how to use it.

Chances are that you just have poor water pressure in your area, Thames Water and the like only have to ensure you get at least 1.5 bar pressure at the boundary, it is not their responsibility from then on... i.e if the water supply pipe has to rise to the 3rd floor you could be getting under 1 bar (worst case) up there, there is not much you can do about it. The fact that it is a new system with new pipework etc. will not really add extra pressure.

Is this a new development or just a new system to an existing flat? If it is a new project the developer should have perhaps added a cold water break tank and pump to raise the pressure to the flats (well top floor flats at least)... but they don't like spending money. I know of a job where the developer refused to pump the water up to a 5 storey high block of flats and it ended up with 0.5 bar up there... this caused so many problems but they just won't spend the money. It is a common problem.

Try http://www.screwfix.com and search for water pressure gauge, let us know what the pressure is... i'll be interested to find out.

 

[alfier]

Yes it's a lot of flats 8 2 on each floor that were converted from an office block with the main water and elect etc being in the ground floor utility room. All the flats have low pressure so you may be right that one can't overcome it easily. I will get the pressure measured but it will take a little while as I'm in Swindon and my daughter is in London SE16.

 

[simond]

There are ways of resolving this type of problem, we do a lot of work with low water supply pressure and flow.

But they do cost and take up space.

Static pressure reading is the place to start, as previously said here.

 

[alfier]

ok got the pressure measured and it's 1.5Bar. Solved some of it which seemed to be a part blockage.

The problem now is the new mixer shower is very weak It's a Triton Polaris and the plumber says Triton are crap as they have too small a valve and it needs replacing with a Mira. He also say's I need a new combi boiler as it only pushes out 9 ltrs min when I need 18 Ltrs a min.

Now as a new shower will involve taking down the new bathroom wall and god knows what a new combi will cost any advise would be appreciated,

Alfie

 

[tonybhoy]

Your plumber's at it.

1.5 Bar aint great mate. A WB 37 CDi needs a minimum of 1.6Bar of incoming mains to produce the quoted 15.1 ltrs/per minute hot water and a 42 CDi combi requires a min of 1.9Bar mains pressure to produce 17.2 ltrs of hot water per minute and even all of that is debatable if the flow rate of the mains is poor and at 1.5bar on a top floor it is bound to be.

The 30CDi will work off 1.4 bar and the 27 CDi 1.2 but both of them have low ltrs per minute at 13 and 11 or thereabouts.

Mira is undoubtedly a better shower manufacturer than Triton but to say that Triton are rubbish is pushing things a tad too far.

Certainly Mira is much more expensive