Very poor shower - Worse when heating used more than norm - Hot water tank - Pump

[gashead86]

Hi Guys,

First and foremost a quick apology should this be in the wrong part of the forum. I have put here in the general section of the forum as frankly I am not entirely sure what part of my plumbing is actually causing the problems...

Cutting a long story short, I essentially have a mains mixer shower that is very poor and is particularity poor in winter months when we are using the heating frequently.
The main problem with the shower is very poor pressure, but also the temperature tends to fluctuate considerably whilst trying to take a shower.

I have a potterton suprima boiler that feeds a hot water tank in my airing cupboard, said tank then leads to a Nabis pump that then feeds the shower. Somewhere along this line there is obviously a plumber.

I have had two plumbers out to look at this and both pretty much scratched their heads. One did seem sure that the problem was linked to the pump as apparently the pump is way louder than it should be. I have also noticed many time sthat the pump sounds like it is really struggling to operate, almost as if it is tryting to push water through the pump quicker than it is being put in. Hope that makes sense!

The pump itself is only a couple of years old and has always sounded horrific since day 1 out of the box. This leads me to believe that the problem is with the supply to the pump rather than the pump itself. But this is purely a hunch.

Has anyone out there ever experienced anything like this? Or more to the point got any ideas as to what might be causing the problem?

Very grateful for any help offered at all guys.

Thanks

Greg

 

[Plumbstar Tom]

First thing I would do is undo the pump flexis and check the feeds have flow and the filters are clean.

Where is the pump sited? Is it single or twin (ie does the pump have one side that pumps or two?)

 

[IDCHAPPY]

How is it supplied to the pump?

 

[gashead86]

First thing I would do is undo the pump flexis and check the feeds have flow and the filters are clean.

Where is the pump sited? Is it single or twin (ie does the pump have one side that pumps or two?)

Hi There,

The pump is in the airing cupboard directly below the tank and approx 40cm away from the shower which is on the other side of the airing cupboard wall in the bathroom.

Is a two sided I believe.

 

[gassafe]

Blocked inlets filters to the pump would be my 1st check...

A plumber should be able to tell if the pump is piped correctly, the look at the shower itself, and possible the thermostat cartridge. Also descaler the shower head.

 

[gashead86]

Hi There,

Pump is twin I believe and the pump is directly below the hot water tank ans is approx 40com away from the shower itself which is located on the other side of the airing cupboard wall in the ensuite.

Pump is fed by standard copper pipe from tank and then onto flexi from pump itself.

 

[gassafe]

If there are isolation valves it should be fairly easy to check the inlet filter on the pump. The shower is nice & local to the pump so it should all be okay.

 

[gashead86]

Not at home at the moment, but fairly sure there is. Think we fitted one to the pipework when the last pump blew up a couple of years ago!

If I am able then I shall pop off the flexi and check for any blockages.

 

[gassafe]

Not at home at the moment, but fairly sure there is. Think we fitted one to the pipework when the last pump blew up a couple of years ago!

If I am able then I shall pop off the flexi and check for any blockages.

Disconnect where the flexi joins onto the pump, should be 2 inlet metal mesh filters!

 

[jam1979]

I would also run the flexis off into bucket to release any trapped air

 

[Masood]

I'm wondering whether the pump is fed off the hot water draw off rather than a flange and is sucking air in...

 

[gashead86]

I'm wondering whether the pump is fed off the hot water draw off rather than a flange and is sucking air in...

Checked the filters and they are all good, so I guess that eliminates that.

The air theory is interesting, I don't know the technicalities, but that is exactly how the pump sounds, as if it is sucking in air rather than water at times leading to it making a terrible noise.

But then why would that only be an issue when the heating is used regularly? As I said before, it is pretty much perfect all the way through the summer.

Thanks for all the help and suggestions so far guys. I really appreciate it.

 

[gassafe]

But then why would that only be an issue when the heating is used regularly? As I said before, it is pretty much perfect all the way through the summer.

its a long shot, but the 3 way valve is passing so when in heating mode it's also heating the cylinder, which when being heated can produce air bubbles in the cylinder (like a kettle boiling) which is benign sucked into the your pump!!

iv also seen a lot of pump flanges piped up wrong, with the vent goin to the pump & the pump supply going to rest of house!!!

Post up a pic if you can, it might be quicker!