Help with shower pump please?!

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Hello everyone.
Hope anyone can help me please. I got a plumber to install a shower pump Grundfos STP 3.0 B to get enough pressure to run a shower and hot water in the basin on my new bathroom. Also bought this one since later I plan to put a new shower on the old bathroom (currently it has an electric shower).

Problem is that, this pump which is supposed to have a low noise operation etc (many reviews online state how quiet it is), it’s nothing like that for me. It’s really noisy and it’s does this pulsating on/off vibrating noise…really loud…so much so that my neighbour can hear it on the other side of the wall. Even worse is that, even if I turn the shower or hot water basin tap on for 10 seconds, it then continues to do the same loud pulsating noise for a good 20minutes after…nothing happens when I turn the cold water tap. Surely this is not normal. It was not a cheap pump!

Is this a sign of a faulty pump or installation issue. What shall I do?

For info, a photo of the set up. I also put a new hot water tank next to it and the cold water tank is in the loft directly above this photo, maybe 1.5/2m above.

For info, I’m completely ignorant when it comes to these things as well, which doesn’t help!

Thanks in advance
 

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Oh dear, that's an installation issue I'm afraid, what a muppet. That pump will happily and wildly resonate it's head off, in what is in essence a resonance chamber of an airing cupboard with it hung to a wall that will just amplify it, especially if the walls are plasterboard.

That needs to be on the floor on a nice thick piece of concrete. Especially if it's got 3 bar worth of horses.
it then continues to do the same loud pulsating noise for a good 20minutes after
Are you saying the pump keeps on hunting (turns on and off) for 20mins after the outlet is closed?
 
Oh dear, that's an installation issue I'm afraid, what a muppet. That pump will happily and wildly resonate it's head off, in what is in essence a resonance chamber of an airing cupboard with it hung to a wall that will just amplify it, especially if the walls are plasterboard.

That needs to be on the floor on a nice thick piece of concrete. Especially if it's got 3 bar worth of horses.

Are you saying the pump keeps on hunting (turns on and off) for 20mins after the outlet is closed?
Yes….if I turn the hot water tap or the shower thermostatic valve (even if on cold) on the new bathroom that is furthest away, even if for 5secs…it starts but then stays on and off doing that horrible loud noise for at least 20 minutes (counted today)!
I thinking about trying to put the pump on the floor (it’s timber tho) on a bit of carpet maybe? It’s on rubber feet so it can’t be screwed down or anything I assume.
Alternative I could try and get a concrete slab, cut a piece just to put it down underneath…but the space is quite tight in the cupboard floor.
Do you think it can be easily rectified then?
 
How far away is the furthest bathroom?

Doesn't matter about a wooden floor but carpet is a waste of time. It needs something that is heavy and wont vibrate, hence the concrete. A slab cut up is fine it just needs to be thick enough, then there nothing for the pump to resonate against. Use pads of silicone adhesive (not sealant) to set the concrete on to the floor with, that will also help absorb vibration.

(edit addition) What's the loud noise, just the pump starting and stopping?

Of course it won't cut out the actual noise of the pump but it does stop the space from amplifying it and the vibrations.
 
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How far away is the furthest bathroom?

Doesn't matter about a wooden floor but carpet is a waste of time. It needs something that is heavy and wont vibrate, hence the concrete. A slab cut up is fine it just needs to be thick enough, then there nothing for the pump to resonate against. Use pads of silicone adhesive (not sealant) to set the concrete on to the floor with, that will also help absorb vibration.

(edit addition) What's the loud noise, just the pump starting and stopping?

Of course it won't cut out the actual noise of the pump but it does stop the space from amplifying it and the vibrations.
I would say in straight runs probably 7-8m to my basin and 9-10m to the shower head.
Yes, the noise is just humming noise from the hunting...all the reviews online say the pump is quite silent which I find it very strange...the spec says it has a noise reducing operation...lol
I can be sat downstairs in the furthest point in the house extension and I can still hear it going...
and I still don't understand why it still keeps on going for 20 min after when everything is shut?!
I have some thick granite and concrete slabs that will be cut soon to do the job.
 
I have a stuart tuner 3 bar pump and the noise is also very audible - I wish I had gone unvented but its too late - These things make noise and there seems to be no way round them

Mine is sat on a plywod base and a rubber mat pecially made for these pumps but still noisy sadly
 
I would say in straight runs probably 7-8m to my basin and 9-10m to the shower head.
OK, shouldn't be too much of an issue at that distance.

The other issue is that 3bar pump will empty that cylinder and the attic cistern in not time at all. Do you know what size the attic cistern is and the size of the HW cylinder? Given the pump is half way up the cylinder the pump could also be drawing the water level down to below the level of the pump in minutes, causing air to be drawn in and causing cavitation and that would cause all sorts of running problems and possibly the behaviour you are describing.

Who fitted the pump, did they come recommended? If the pump is drawing in air or running dry it can easily be damaged in no time at all. Do know you will always have a certain amount of noise when the pump is running - your is rated @<70Db @1m
 
OK, shouldn't be too much of an issue at that distance.

The other issue is that 3bar pump will empty that cylinder and the attic cistern in not time at all. Do you know what size the attic cistern is and the size of the HW cylinder? Given the pump is half way up the cylinder the pump could also be drawing the water level down to below the level of the pump in minutes, causing air to be drawn in and causing cavitation and that would cause all sorts of running problems and possibly the behaviour you are describing.

Who fitted the pump, did they come recommended? If the pump is drawing in air or running dry it can easily be damaged in no time at all. Do know you will always have a certain amount of noise when the pump is running - your is rated @<70Db @1m
A very good point - It should have been fitted from the side entry
 
OK, shouldn't be too much of an issue at that distance.

The other issue is that 3bar pump will empty that cylinder and the attic cistern in not time at all. Do you know what size the attic cistern is and the size of the HW cylinder? Given the pump is half way up the cylinder the pump could also be drawing the water level down to below the level of the pump in minutes, causing air to be drawn in and causing cavitation and that would cause all sorts of running problems and possibly the behaviour you are describing.

Who fitted the pump, did they come recommended? If the pump is drawing in air or running dry it can easily be damaged in no time at all. Do know you will always have a certain amount of noise when the pump is running - your is rated @<70Db @1m
I can't remember exact but I believe they both are around or over 100 ltrs.
ive never run out of water with the newer tanks (and I have 3 women in the house). My brother in law fitted the whole system.
A very good point - It should have been fitted from the side entry
But the tank does have a side entry...ive checked. I would have to create an opening...sounds like a very tricky job.
Im really hoping that putting the pump on the floor will resolve it. Fingers crossed!
 
I can't remember exact but I believe they both are around or over 100 ltrs.
ive never run out of water with the newer tanks (and I have 3 women in the house). My brother in law fitted the whole system.

But the tank does have a side entry...ive checked. I would have to create an opening...sounds like a very tricky job.
Im really hoping that putting the pump on the floor will resolve it. Fingers crossed!
It should come out of the side otherwise you will have air in the pump - Do it once and proeprly
 
It should come out of the side otherwise you will have air in the pump - Do it once and proeprly
But shouldn’t then the tank have an entry/connection on the side? Is it normal and easy to create one on a round copper cilinder? This diagram shows from the top!?

1705827445003.jpeg
 
It does have a warwix flange so that is there to minimise air getting to the pump.
But the tank does have a side entry
Does or doesn't? An essex flange could be cut into the side of the cylinder but may not be needed.

The trouble with a 3bar pump is that is moves water very quickly, it can in some instances draw water faster then the cylinder and the attic cold water cistern (CWSC) can replace it. Without being onsite it is really hard to suggest whether the supply and pipework is suitable to feed that chunky pump. I presume the supply to the cylinder from the cistern is 22mm?

I'd certainly move it to the floor to start with, then see how things go from there. I'd also run the pump on an outlet to test it's max output and see how the supplies deal with the draw. Can I ask, is your BIL qualified/experienced?
 
It does have a warwix flange so that is there to minimise air getting to the pump.

Does or doesn't? An essex flange could be cut into the side of the cylinder but may not be needed.

The trouble with a 3bar pump is that is moves water very quickly, it can in some instances draw water faster then the cylinder and the attic cold water cistern (CWSC) can replace it. Without being onsite it is really hard to suggest whether the supply and pipework is suitable to feed that chunky pump. I presume the supply to the cylinder from the cistern is 22mm?

I'd certainly move it to the floor to start with, then see how things go from there. I'd also run the pump on an outlet to test it's max output and see how the supplies deal with the draw. Can I ask, is your BIL qualified/experienced?
Sorry! Doesn’t have one!

Yes, 22mm from the cold water tank.
The installer is my brother in law who has been a plumber for over 20 years…everyone makes mistakes I suppose! Hopefully moving it to the floor will rectify it.

I still don’t understand why the pump continues to do that horrible loud noise for that much time even after everything is turned off!? That doesn’t make sense to me!

Also the power on the shower is better than it was without the pump of course but I was expecting a lot more power, especially if you guys are saying 3bar is a lot of horses!?

By a “great chance of luck”, you don’t work in Sheffield do you? Lol
 
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Excuse me butting in - but it seems to me that there has been some confusion and 'cross-purposes' regarding the "side Entry" mentioned by JackK in post no.8. Your HW cylinder doesn't have and doesn't need a flange fitted on the side (an Essex Flange) - you already have a flange fitted at the top of the cylinder. Trouble is - it's been plumbed the wrong way round. The air-free outlet at the side of the flange should be connected to the shower pump to prevent air reaching the pump, as shown in the diagram in post no. 11. In fact, the pump has been connected to the top outlet of the flange. I think these connections should be reversed. See attached diagram
Flange.jpg
 
The installer is my brother in law who has been a plumber for over 20 years…everyone makes mistakes I suppose! Hopefully moving it to the floor will rectify it.
Apologies, I'm not suggesting that your BIL hasn't installed it correctly, it was just to understand whether the installer was experienced or not. That and the fact that he isn't back sorting it out for you as I wouldn't have expected an experience resource to not ensure that everything was ok, or be back to sort it. Though I must be honest the pump sitting on that little platform was always going to be really noisy.
you already have a flange fitted at the top of the cylinder. Trouble is - it's been plumbed the wrong way round. The air-free outlet at the side of the flange should be connected to the shower pump to prevent air reaching the pump
No it hasn't, the flange they have is a Warwix flange, not a Surrey (S) flange. A warwix flange vents to the side and the dip tube air free water is the centre tube, a surrey flange is the other way around, as per your diagram. Have a look at the flange that is fitted to the top of the cylinder in the first pic

Surrey Flange, top vent --------------- Warwix flange, side vent

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