Power Shower install - some kind of cold water supply fault

[lloydie33]

Dear all,

I've just had a new Hudson Reed (thermostatic, twin controls) shower installed with new tank, pipework and a 3bar stuart turner pump (twin). Its set up to power the other shower downstairs too.
The problem is that the new shower sometimes doesn't have sufficient flow- through to kick off the pump. The one downstairs always kicks off fine.
On investigation to check the flows... with the pump turned off if I over-ride the 38oC stop then the hot water comes through ok (considering it only has 1.5m head) but the cold water doesn't come through. If I remove the shower head and try to suck the water through (in case of an air lock) I still get virtually no flow and a lot of resistance if the valve is set to below the 38oC point.

Please could anyone suggest further diagnoses, or any ideas at all.

My current thoughts are:
The cold water is not getting through the shower valve - blocked filter or dodgy non return valve?
Antiscald valve is dodgy?

Just to say if the pump does kick in then you get a decent shower!

Many thanks,

Steve

 

[seco services]

whats the cold like to the other shower without the pump running ?

 

[lloydie33]

Hi,
Just checked that and it seems pretty good, though of course being downstairs it has a decent head. Just to be clear I tried it with pump off and only cold water on, with shower valve set to <20oC.

I tried the new shower too with pump off and only cold water on, with shower valve set to cold - no flow. If I suck on the end of the shower hose there is strong resistance to any flow, though I can get a little water out.

Many Thanks,

Steve

 

[seco services]

have you any isolation valves between the pump and new shower that maybe not fully open.
if not can only be a blocked filter or faulty non return valve as you said on the pipework to the new shower.

 

[lloydie33]

There are isolator valves on the 22mm pipework for both hot and cold but they are upstream from the pump and therefore isolate the old and new shower supply.

I'm hoping the rather nice and 'just finished' tiles don't have to be disturbed...

Thanks again for your quick response, I will see what can be done to get at the inlet filter & non-return valve. The mixer is recessed into a stud wall, mounted on ply.

Cheers, Steve

 

[lloydie33]

I've been asking around and have just had the suggestion from Hudson Reed was that there could be this kind of problem if there are 2 non-return valves, e.g. one on the pump and one in the shower valve (the Hudson Reed diagram clearly shows it). Apparently its quite easy to have it so that the pressure between them is higher than atmospheric and so on opening the shower valve there is no reason for the valve to open and allow flow.

Does this sound resonable?

The suggestion was to remove the valve in the shower mixer, this may be somewhat awkward to do...

Cheers, Steve

 

[seco services]

have you got any more non return valves fitted apart from the one in the mixer valve ?

 

[lloydie33]

I phoned Stuart Turner and they said there are none fitted to the positive pressure monsoon pump. So it looks like there are only the ones fitted to the mixer (1 hot, 1 cold).

Trying again tonight with the new mixer turned to cold and with the other shower running, it then worked fine.
Turned the old shower off, then sucked through the water on the new shower...some resistance then the water flowed fine, either set to hot or cold. So looks good for now. Maybe its just a bit sticky.

Hudson Reed were also very helpful and have sent me 2 non-return valves just in case.

Thanks again for your help.

Cheers, Steve

 

[lloydie33]

Aaarrgh...
Dear all,
I thought things were ok but after the other shower downstairs is turned off and everything left for say 10mins, then I still don't get any flow either hot or cold through the new Hudson Reed (HR) shower valve upstairs (no shower head on).
In detail; if I turn the pump off, then turn the thermostat valve on the HR valve to hot I get no flow unless I suck on the shower hose, then again after some resistance I get good flow that keeps going. If I turn the valve to cold then I get no flow & even if I suck hard on the shower hose I still get no real flow - though I can feel the resistance (vacuum).
I does sound like sticky non-return valves. However, although the hot is much easier to get flowing, surely not both of the HR non-return valves are that sticky?
I have replaced the downstairs shower valve so there is now no dripping and thus potential for airlocking or vacuum affecting the upstairs HR non-return valves.

Any suggestions for further diagnosis would be most welcome?

Cheers, Steve

 

[lloydie33]

Would the hot water supply significantly 'leak' through into the cold water (or visa versa) if I removed the inlet non-return valves in the new Hudson Reed shower?

I suspect that if I could remove the non-return valves then the flow would be much better, no matter what other problems might exist.

Cheers,

Steve

 

[v17kas]

Hi,

I too have a twin Stuart Turner pump and HR shower (PIN001) with the same issue.

Please advise if you managed to resolve this issue in the end?

Thanks in advance,

Vik