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That's a fair assumption, the other question I'd ask is did the builder flush the main thoroughly before connecting onto the new system within the house?

That we don't know. The whole property was redone so a lot of the time he was with his team just doing their thing.

I just phoned my father who also confirmed that the pipe is more or less straight from the water main to the stopcock. The only time it bends is in the utility room, to connect to the copper pipe / stopcock.


Apologies for sounding dense, but I still can't get my head around how/why if we are getting 18l/min into the property, two taps cannot be on at the same time providing 8l/min each?
 
It should have been checked first then a system designed to what flow/pressure was available or achievable. It's kind of past that stage now though?
 
You could search for the 6 litres for ever. You currently have with no restrictions 24lpm. Even that is poor for a property your size.
To make things work well the system should have been designed to give EACH bathroom between 20-30lpm.

Whilst all that is true, at the moment we have 3 people living there. At most two bathrooms are being used at the same time so we could get away with the 24l/min we are expecting. In a few years time when we may have more people living there we can invest in a break tank and pump.
 
It should have been checked first then a system designed to what flow/pressure was available or achievable. It's kind of past that stage now though?

Very much so. Thanks to you guys I know now what should have been done and will bear that in mind for next time (I hope there isn't a next time though as this house was a pain). However, the question is what do we do now.
 
Very much so. Thanks to you guys I know now what should have been done and will bear that in mind for next time (I hope there isn't a next time though as this house was a pain). However, the question is what do we do now.

I wasn't digging mate it was just a reply to an earlier post.
 
What about hosepipe on outside tap and use to bypass parts of the install to isolate the problem ?
 
What about hosepipe on outside tap and use to bypass parts of the install to isolate the problem ?

Sorry, I don't get what you mean? The outside tap gets 18l/min and branches off after the water filter. How could we use that to isolate parts of the system?
 
After the filter ? . cut pipework near a bathroom and connect hosepipe there, connect direct to unvented cyl ?
 
Sorry, I don't get what you mean? The outside tap gets 18l/min and branches off after the water filter. How could we use that to isolate parts of the system?
Your outside tap shouldn't be filtered or softened,
 
After the filter ? . cut pipework near a bathroom and connect hosepipe there, connect direct to unvented cyl ?

Sorry, I lie. It branches off the kitchen line, which is before the softener.

All the pipework is in the walls/under the floor and is near impossible to get to. I don't see what this would prove, since we do have two outlets very close to the stopcock (one about 75cm away and one 4m away) and we experience the issue where is the second tap is turned on the flow is halved in the first (both to 4l/min).
 
So
24 lpm at mains ( so water board say!)
18 from before softener, 6 lpm lost ( this might be all you can get through that tap at your pressure)
12 at outlets (probably restricted by softener, hoses and valves.)

therefore when running two outlets you get 6 lpm .
 
Sorry, I lie. It branches off the kitchen line, which is before the softener.

All the pipework is in the walls/under the floor and is near impossible to get to. I don't see what this would prove, since we do have two outlets very close to the stopcock (one about 75cm away and one 4m away) and we experience the issue where is the second tap is turned on the flow is halved in the first (both to 4l/min).
Am not onsite so :)
 
is there enough room for jase to take the stopcock off the imcoming main to double check what flow you have before it? obviously linking up back to outside so as not to flood the place
 
So
24 lpm at mains ( so water board say!)
18 from before softener, 6 lpm lost ( this might be all you can get through that tap at your pressure)
12 at outlets (probably restricted by softener, hoses and valves.)

no 18 at outlet of iso before tap, 6l/min from outlet of tap, when its on its own, no other outlets running.

2 outlets reduces flow to 4l/min
 
is there enough room for jase to take the stopcock off the imcoming main to double check what flow you have before it? obviously linking up back to outside so as not to flood the place

There is space if we move the water filter out of the way, which is fairly easy to do.

I was also thinking, if we think its the mains pipe that could be the issue, can we temporarily put another one from the meter to the stopcock (run it through the house). Then we can see how everything behaves?
 
There is space if we move the water filter out of the way, which is fairly easy to do.

I was also thinking, if we think its the mains pipe that could be the issue, can we temporarily put another one from the meter to the stopcock (run it through the house). Then we can see how everything behaves?

This is what I am thinking!

step 1, disconnect mains and connect new mains to outside, do dynamic pressures and flow rate with open outlet
step 2, reconnect mains with new pipe from meter (if accessible) to house
step 3, do dynamic pressures on mains with system connected
step 4, check every single outlet (that is accessible) for dynamic pressure, flow before and after taps.
step 5, buy one tap and replace in several places to see if this makes a difference
step 6, breaker tank and pump

Obviously if it any of the above fixes it then we know the issue.

I believe it is the mains for these reasons:

The flow may be good but the pressure can be bad, due to reduced pipework size.
For instance if you put your hand over a hose pipe, you think the water is coming out really fast (flow or L/min), however if you were to measure it, it is actually really low (Bar/ Dynamic pressure)

So a blockage could be giving a good flow rate but the pressure is low.
This in turn would hit the taps and the taps would then restrict it even more.

For example if you were to run a hose and twist it a little in the middle, you will still get a reasonable flow, however if you were to kink it twice it would barely dribble out.

Hope this explains it well!! someone might be able to explain it better.

Just out of curiosity, did you fall out with the builder at any point?
 
We haven't fallen out with him but towards the end of the work (interior decorating) he started asking for more money. That was after all the plumbing was done so he couldn't have done something to it. We actually came to an agreement a few weeks ago to give a little more money and that is when he came back to do the utility room sink etc.

So for the above, how much would steps 1 to 5 cost me?
 
We haven't fallen out with him but towards the end of the work (interior decorating) he started asking for more money. That was after all the plumbing was done so he couldn't have done something to it. We actually came to an agreement a few weeks ago to give a little more money and that is when he came back to do the utility room sink etc.

So for the above, how much would steps 1 to 5 cost me?

I would suggest that's not for open forum, but that's just my opinion.
 
This is what I am thinking!

step 1, disconnect mains and connect new mains to outside, do dynamic pressures and flow rate with open outlet
step 2, reconnect mains with new pipe from meter (if accessible) to house
step 3, do dynamic pressures on mains with system connected
step 4, check every single outlet (that is accessible) for dynamic pressure, flow before and after taps.
step 5, buy one tap and replace in several places to see if this makes a difference
step 6, breaker tank and pump

Obviously if it any of the above fixes it then we know the issue.

I believe it is the mains for these reasons:

The flow may be good but the pressure can be bad, due to reduced pipework size.
For instance if you put your hand over a hose pipe, you think the water is coming out really fast (flow or L/min), however if you were to measure it, it is actually really low (Bar/ Dynamic pressure)

So a blockage could be giving a good flow rate but the pressure is low.
This in turn would hit the taps and the taps would then restrict it even more.

For example if you were to run a hose and twist it a little in the middle, you will still get a reasonable flow, however if you were to kink it twice it would barely dribble out.

Hope this explains it well!! someone might be able to explain it better.

Just out of curiosity, did you fall out with the builder at any point?
Think about this jase, a blockage would give reduced flow rate
 
I'm with dancing on this. Nighmare jase .You can change taps and youl still have the same issue i think as because multiple outlets are poop flow you need to trace back to where it's better . There will be one problem that's causing many poor outlet flow rates. I know it's not easy but replacing taps won't really help . Not good to do but it's process of elimination. Tees need to be cut in certain bits if accessible n gauges put on or valves to measure different points ... Like ermi said earlier a tee in too far with a certain fitting it's just finding it. Good luck bud and patience n perseverance.
 
24 lam at the mains is poor to start with and if only 18 at the softner then that would indicate to me that the problem is outside. Not inside.
 
Also I'd disconnect the non return valve that should be near the mains and try it without it.
 
24 lam at the mains is poor to start with and if only 18 at the softner then that would indicate to me that the problem is outside. Not inside.

Whilst it may be poor, why can't I have two taps on at 8l/min with 2l/min to spare?
 
Hi there hshah the tests you guys done to get these figures did you do the checks a couple different times to see if any variation In results. Stick presdure gauges on get your bar reading at stopcock and open outlets and check if gauge drops dramatically. . What was your bar reading on incoming main ?
 
Think about this jase, a blockage would give reduced flow rate

Yeah which is hopefully how I explained it!! Reduced flow to 18 l/min but when faced with the taps, the pressure isn't there to help with the flow which is why it reduces down to 6l/ min?
i am not very good at explaining principles of plumbing.
 
24 lam at the mains is poor to start with and if only 18 at the softner then that would indicate to me that the problem is outside. Not inside.
Provided water board are telling truth and not covering their own backsides.
 
Also I'd disconnect the non return valve that should be near the mains and try it without it.

No NRV, no drain valve, pretty sure the pipe wasn't flushed and probably left in trench for few weeks whilst other work was done with nothing on the ends of pipes.

pretty sure it is mains inlet but only one way to find out, problem is the main is in centre of house, all newly tiled floors.
 
If you are going to run a temp pipe to an outlet further on, then use it to "blow back" into a large tub to flush back anything that could possibly be in there and do the same with the MDPE with the stopcock removed and being controlled from the street in short bursts.
 
i would check this if there a water meter fitted ? turn all off in the house (stopcock) and see if meter still spins (possible leak outside if does )

2bar is low for standing pressure

I had similar problem a few months ago but was a shared main someone bodged a section with little bits of copper and some pushfit crap
 
Affinity Water had cut the main before the meter to test the flow and pressure there... they recorded 24l/min and 2 bar.

We are seeing 2 bar after the stopcock and water softener, so all that is being lost is the flow (from 24l/min to 18l/min).
 
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