Low Flow/Pressure

[hshah]

Hshah, where did the taps come from? Did u buy them or did the builder?

We bought them. The kitchen one is a Franke Kubus FilterFlow:
Franke FilterFlow Taps Kubus Hand spray SilkSteel

Trying to find the receipts for the other ones and the showers so I can tell you which ones they are. I do know they are all decent named brands.

 

[hshah]

These are what they are:

The only exception is the utility room tap which is a random one from Wickes.

 

[BLOD]

2 bar standing pressure at garden tap ? how many floors has the house got ? did you measure the dynamic pressure ?

 

[jase158]

https://www.ukbathroomstore.co.uk/phoenix-vp065-round-thermostatic-bar-valve-and-rigid-riser
En suite shower should be fine- suitable for low pressure, minimum of 0.5 bar?

 

[jase158]

Phoenix Square Stainless Steel Thermostatic Shower Column - SC002

This one requires 2 bar minimum pressure?

 

[jase158]

The rest are all low pressure showers so should work ok?

 

[hshah]

The rest are all low pressure showers so should work ok?

The issue is with all the showers and taps... as soon as another outlet is turned on the flow drops significantly.

 

[hshah]

Phoenix Square Stainless Steel Thermostatic Shower Column - SC002

This one requires 2 bar minimum pressure?

Wasn't the pressure coming up to the taps 2 bar? Obviously it will drop a little since its upstairs and would explain why that shower is weaker than the rest, but doesn't explain the flow issue we have.

 

[hshah]

2 bar standing pressure at garden tap ? how many floors has the house got ? did you measure the dynamic pressure ?

Dynamic pressure question is for jase, but I can answer the floors one... 3 floors including ground floor (one shower on ground, two on first and one on second).

 

[Ermintrude]

Ok. Pipe work right sizes? Have u checked that pipe isn't inserted too far into a tee? Or cheap ISO fitted?

Had one where branch on tee obstructed 95% of main pipe.

Not piped in 10mm is it? Sounds very much like an obstruction. 25mm mdpe restricted? Pebble?

Fit a tee on mdpe. Measure flow rate and dynamic pressure.

 

[hshah]

Ok. Pipe work right sizes? Have u checked that pipe isn't inserted too far into a tee? Or cheap ISO fitted?

Had one where branch on tee obstructed 95% of main pipe.

Not piped in 10mm is it? Sounds very much like an obstruction. 25mm mdpe restricted? Pebble?

Fit a tee on mdpe. Measure flow rate and dynamic pressure.

I will leave it to jase to answer the "technical" questions, but for my benefit, would a blockage really result in what we are experiencing? We know we are getting 18l/min after the water softener and to the taps... just went multiple taps are on the flow drops to about 4l/min.

 

[Ermintrude]

Yes . Very much so.

 

[Toxic Ted]

Sounds to me like a restriction in there somewhere. I've had foreign objects in the pipework before from a pebble to marbles (disgruntled builder), but when this is the case you normally get a spurt of decent pressure followed almost instantly by the drop.

 

[hshah]

Sounds to me like a restriction in there somewhere. I've had foreign objects in the pipework before from a pebble to marbles (disgruntled builder), but when this is the case you normally get a spurt of decent pressure followed almost instantly by the drop.

I think the pressure/low is consistent when an outlet is turned on, until another one is turned on.

How would one go about confirming there is a blockage, locating it and then clearing it?

 

[Ch4 plumbing]

I would look back to post #26 Jase, if the water board are to be believed at the meter you have 24ltr a min and at the stop tap as the new main enters the house you have 18ltrs a min! How longs the new water main? Your losing upto 6ltrs a min just their!

 

[hshah]

I would look back to post #26 Jase, if the water board are to be believed at the meter you have 24ltr a min and at the stop tap as the new main enters the house you have 18ltrs a min! How longs the new water main? Your losing upto 6ltrs a min just their!

It is about 15m of the blue pipe, which is going straight from the water meter to the stopcock.

 

[Ch4 plumbing]

Could even be a possible fault with the nrv in the meter.

 

[hshah]

Could even be a possible fault with the nrv in the meter.

The Affinity Water guy who came to check everything a while back said all that was fine. His conclusion was that our builder had kinked the pipe, but he only checked the mains, meter and the water tap in the back garden.

 

[Ch4 plumbing]

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?

 

[Chalked]

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.

 

[hshah]

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?

 

[Ch4 plumbing]

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?

 

[hshah]

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.

 

[hshah]

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.

 

[Ch4 plumbing]

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.

 

[hshah]

I wasn't digging mate it was just a reply to an earlier post.

And no offence was taken

 

[dancinplumba]

What about hosepipe on outside tap and use to bypass parts of the install to isolate the problem ?

 

[hshah]

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?

 

[dancinplumba]

After the filter ? . cut pipework near a bathroom and connect hosepipe there, connect direct to unvented cyl ?

 

[Chalked]

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,

 

[hshah]

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).

 

[hshah]

Your outside tap shouldn't be filtered or softened,

Sorry, I was wrong. See post above please.

 

[Chalked]

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 .

 

[dancinplumba]

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

 

[PlumbBobBob]

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

 

[jase158]

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

 

[hshah]

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?

 

[jase158]

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?

 

[hshah]

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?

 

[Ch4 plumbing]

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.

 

[hshah]

I would suggest that's not for open forum, but that's just my opinion.

Jase can just text me a quote

 

[dancinplumba]

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

 

[hshah]

Think about this jase, a blockage would give reduced flow rate

So that would explain the drop from 24l/min to 18l/min, but I still don't get why I can't have two outlets on at 8l/min.

 

[kris]

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.

 

[kris]

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.

 

[kris]

Also I'd disconnect the non return valve that should be near the mains and try it without it.

 

[hshah]

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?

 

[dancinplumba]

If nrv on main then exp vessel is a must

 

[kris]

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 ?

 

[jase158]

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.