Low/High Mains pressure

[V1k_10]

Good evening all.

My mains water pressure seems to be quite low in some parts of the house. On flushing the 1st floor WC, the cistern does not fill up by itself to illustrate this. On turning on and off the bath cold water tap, the cistern seems to then fill up

The ground floor pressure seems to be okay although during summer months, the garden tap does not have lots of pressure either.

I've let the water company know and they came out today to test this. I'm currently isolating because of the Covid-19 so the engineer plugged a tap in outside and tested the water pressure at the boundary of the property and told me that I'm getting 28 (I think it was litres per minute but could be wrong) and that the house is fed by a 15mm metallic pipe.

Seeing the pressure at the boundary, it seemed that it was an internal issue which will be a nightmare to diagnose as there is wooden flooring laid across the hallway where the mains pipe comes in. Digging up the front drive will also not be an option in all honesty.

I currently have a gravity fed hot water system and wanted to ask if in anyone's professional opinion a mains water pump would be advisable? If so, which models of pump are good and hard waring?

Many thanks in advance.

 

[TeaAndBiscuits]

Is it just the WC filling slowly/not at all where this problem manifests?

If so then it sounds like a sticking fill valve. I had a similar issue. When you turn on the cold tap and shut it again the water moving in the pipework has to stop this causes a small pressure spike. This then pushes the fill valve open.

 

[Madrab]

Salamander Homeboost - Grundfos Home Booster - Stuart Turner mainsboost, all the mains pump suppliers do one now. Salamander's is a bolt on, in line pump and has probably been about the longest. The others are just as good, ST are my pump of choice but that's mostly on distribution supplies (gravity fed outlets/showers) rather than mains pumping.

You are limited to a supply of 12L/Min with a pressue of around 1-1.5bar.

 

[hard-work]

Firstly, is this a recent problem, or ongoing?
If the mains pressure is the problem, not the toilet inlet valve, then the first port of call is the main stopcock. What is the flow/pressure like just after that? Sometimes a main stop cock can collapse. If this looks a problem, then change it for a full bore stop cock, then see what it is like.

 

[hard-work]

Salamander Homeboost - Grundfos Home Booster - Stuart Turner mainsboost,

Why would anyone want to buy one of those when the flow at the boundary is 28 litres/min?

 

[V1k_10]

Thanks everyone, this started a fair while back - maybe a year or so ago now. everything was find until the water company shut the water supply down as they had to change a pipe along the road.

When they turned the water back on again, the pressure was lower. I spoke to them at that point too and they came out and tested but their answer was the same then too.

the problem is not just with the WC, the shower unit (electric) literally gets no pressure at all and so we can longer use it. The header tank in the loft also takes it's time to fill and sometimes also only fills when the bath tub cold tap is switched on and off....

The main stop cock is in the drive way with 8" on concrete around it and so changing that would be a real job in itself..... If at all possible, I'd much rather leave that alone and try an alternative?

 

[hard-work]

I think debris may have been disturbed blocking one of the the stopcocks. You have one inside the house as well, check that and the flow/pressure at that point. When checking then change to a full bore at the same time.

If the flow/pressure is poor at the stopcock inside the house, then it point to the water companies work. It will not be a coincidence. They will fob you off unless you can prove to them it is their work.

 

[V1k_10]

Unfortunately there's no way that I could prove it was them as it was so long ago now. I listed it after they messed about with he supply but whether they would accept that as proof is doubtful?

I only have the 1 stopcock located in the front drive. The next stopper along the line is the isolator for the kitchen tap but this does not stop the flow in the mains line, just the kitchen sink. There's nothing in between this isolator and the stop cock in the driveway unless it's under the concrete in the drive without any access to it?

There is a stop cock on the pavement literally 2" from the boundary of my property? Could this be the 2 stop cocks?

 

[Mr.B]

I recently rang South West Water to say I couldn't shut my main stop valve completely off (it's in the pavement outside the house) ... it kept letting by when I turned it off and prevented me from doing some internal work.

They turned up and the fella replaced the top half of the tap with a new one.

And since it has been fixed the flow to my house has improved quite markedly. I'd suspected the flow had been slowing down over a period of months.

The rubber washer in the old tap had disintegrated and I'm guessing that a piece of the old washer had jammed in the tap body and was restricting the flow.

Maybe something similar happening with the OP?

 

[hard-work]

The stopcock under the concrete drive needs looking at. Tell the water company it is the only stopcock on the line so is theirs with them having to fix it. They may want proof that the flow/pressure is poor inside the house, so a pressure/flow test after the kitchen stoptap. If poor then it points to them and their work.

 

[denso13]

Tell the water company it is the only stopcock on the line so is theirs with them having to fix it.

It doesn't matter if it's the only one. The end user is responsible for everything on their land and the water company are responsible for everything outside this.This is why main stopcocks are normally in the pavement or road.

 

[hard-work]

It doesn't matter if it's the only one. The end user is responsible for everything on their land and the water company are responsible for everything outside this.This is why main stopcocks are normally in the pavement or road.

I do believe that the water company have to provide a stop valve. If it is not on their side then it is on the other. The 1st valve on the lines is still their properly no matter where it is. They can always fit one in the pavement if they want to. If they do then they had better ensure the 18 litres/min reaches your house.

 

[denso13]

The 1st valve on the lines is still their properly no matter where it is.

No, it really isn't https://www.ofwat.gov.uk/households/supply-and-standards/supply-pipes/

 

[denso13]

Do you ever read the links you give? Or more importantly understand them?

Yes, what you have quoted backs up exactly what I said.

Are you hard of reading or what?

 

[denso13]

The pipe in question, in the OP's property is a supply pipe as described in the page I linked to. Therefore point three is relevant in your quote which says,

Stop-taps along the length of the supply pipe, and any water fittings, are the property owner’s responsibility to maintain.

Where on earth does that say it is the Water Companies responsibility? Whose responsibility is it according to the point 3 above you quoted?