Ask The Trades - Shower problem.

m GDPR opt-out	Shower problem. Sep 14^th, 2011, 2:10pm Hi all, I have just fitted a thermastat controlled mixer shower to my bath. However, when running the water it pulsates and wont run as a continuous spray, although the temperature stays constant. Any idea why? Thanks M.
Back to top	IP Logged

m GDPR opt-out	Re: Shower problem. Reply #1 - Sep 14^th, 2011, 4:24pm Perhaps I should add, we have an immersion heater and mains cold feed. Looking at the diagrams in the instructions this is apparently an unvented system and the shower should work ok with this system.Oh, and it's a Hansgrohe.
Back to top	« Last Edit: Sep 14^th, 2011, 4:26pm by melvinhill » IP Logged

TIMBA-WOLF Board Moderator Offline Timba-Wolf..... Var@*sh, should be banned!! Posts: 7158 Total Thanks: 15 For This Post: 0 KENT,(under a tree!!!!) United Kingdom Gender: Trade: Joiner	Re: Shower problem. Reply #2 - Sep 14^th, 2011, 5:02pm Out of curiosity, what sort of hand set (shower head) is on the hose, as some like the one we have is a multi head, and has a PULSE setting..... as well as many spray patterns...
Back to top	AS HONEST AND LOYAL AS THE TIMBER-WOLF. --VAR@*SH, DON'T YOU SWEAR AT ME!! PAL!!&&I DON'T SUFFER FROM INSANITY- I DAMNED WELL ENJOY IT!!!!! IP Logged

Lectrician Administrator Trade Member Author Offline Ask The Trades Posts: 8815 Total Thanks: 109 For This Post: 0 Braunton, North Devon United Kingdom Gender: Trade: Electrician	Re: Shower problem. Reply #3 - Sep 14^th, 2011, 5:11pm Are you saying it is mains pressure cold water and cylinder fed hot water - the cylinder fed from a header tank in the loft?
Back to top	Need to post a picture? Click HERE for info! IP Logged

m GDPR opt-out Total Thanks: 109 For This Post: 0	Re: Shower problem. Reply #4 - Sep 14^th, 2011, 5:40pm TIMBA-WOLF wrote on Sep 14^th, 2011, 5:02pm: Out of curiosity, what sort of hand set (shower head) is on the hose, as some like the one we have is a multi head, and has a PULSE setting..... as well as many spray patterns... Timba wolf; There's no mention of a pulse setting and it seems to do it on all settings.
Back to top	IP Logged

m GDPR opt-out Total Thanks: 109 For This Post: 0	Re: Shower problem. Reply #5 - Sep 14^th, 2011, 5:45pm Lectrician wrote on Sep 14^th, 2011, 5:11pm: Are you saying it is mains pressure cold water and cylinder fed hot water - the cylinder fed from a header tank in the loft? Lectrician; That's the one, except the header tank is about a foot above the hot tank in the same cupboard in the back bedroom and not in the loft.
Back to top	IP Logged

Lectrician

Administrator
Trade Member
Author

Offline

Ask The Trades
Posts: 8815

Total Thanks: 109
For This Post: 0

Braunton, North Devon
United Kingdom
Gender: male

Trade: Electrician

Re: Shower problem.
Reply #6 - Sep 14^th, 2011, 5:48pm

I am not a plumber, but I believe that the hot and cold feed to the mixer needs to be balanced, meaning either both tank fed, or both mains fed.

I would assume the cold tap to the bath would be better fed from the header tank, or a pressure reducing valve used.

The hot water may not have sufficient pressure for the mixer with only a foot of height - do you know the minimum operating pressure of the mixer?

Scruff will be likely on later and be able to advise exactly.

Back to top

« Last Edit: Sep 14^th, 2011, 5:49pm by Lectrician »

Need to post a picture? Click HERE for info!

IP Logged

Lectrician Administrator Trade Member Author Offline Ask The Trades Posts: 8815 Total Thanks: 109 For This Post: 0 Braunton, North Devon United Kingdom Gender: Trade: Electrician	Re: Shower problem. Reply #7 - Sep 14^th, 2011, 5:51pm Can you give us a link to the one you have bought, a link to the manual, or a scan/photo of it?
Back to top	Need to post a picture? Click HERE for info! IP Logged

m

GDPR opt-out

Total Thanks: 109
For This Post: 0

Re: Shower problem.
Reply #8 - Sep 14^th, 2011, 6:00pm

Lectrician wrote on Sep 14^th, 2011, 5:48pm:

I am not a plumber, but I believe that the hot and cold feed to the mixer needs to be balanced, meaning either both tank fed, or both mains fed.

I would assume the cold tap to the bath would be better fed from the header tank, or a pressure reducing valve used.

The hot water may not have sufficient pressure for the mixer with only a foot of height - do you know the minimum operating pressure of the mixer?

Scruff will be likely on later and be able to advise exactly.

Thanks for that Lectrician, the recommended operating pressure is 0.2-5 bar.

Back to top

IP Logged

m GDPR opt-out Total Thanks: 109 For This Post: 0	Re: Shower problem. Reply #9 - Sep 14^th, 2011, 6:06pm Lectrician wrote on Sep 14^th, 2011, 5:51pm: Can you give us a link to the one you have bought, a link to the manual, or a scan/photo of it? http://www.plumbworld.co.uk/link/1/pwhg0015installation.pdf
Back to top	IP Logged

CWatters

Super Member

Offline

"Daddy fick it" says James

Posts: 5150

Total Thanks: 58
For This Post: 0

Gender: male

Re: Shower problem.
Reply #10 - Sep 14^th, 2011, 6:47pm

I'm not a plumber either but... does it do it with the shower hose or head disconnected?

Perhaps the high cold pressure is causing the pressure in the mixer assembly to exceed that in the hot pipe. eg preventing or reducing the hot flow. The mixer would react to that by turning down the cold flow. That might cause the pressure to drop allowing the hot to flow again and triggering the mixer to open the cold again. eg oscillation and pulsing flow.

If removing the head/hose stops it pulsing then perhaps look at putting a pressure reducer in the cold flow.

Back to top

IP Logged

m

GDPR opt-out

Total Thanks: 58
For This Post: 0

Re: Shower problem.
Reply #11 - Sep 14^th, 2011, 8:54pm

CWatters wrote on Sep 14^th, 2011, 6:47pm:

I'm not a plumber either but... does it do it with the shower hose or head disconnected?

Perhaps the high cold pressure is causing the pressure in the mixer assembly to exceed that in the hot pipe. eg preventing or reducing the hot flow. The mixer would react to that by turning down the cold flow. That might cause the pressure to drop allowing the hot to flow again and triggering the mixer to open the cold again. eg oscillation and pulsing flow.

If removing the head/hose stops it pulsing then perhaps look at putting a pressure reducer in the cold flow.

Thanks CWatters, but it still does it without the shower head on

Back to top

IP Logged

Lectrician Administrator Trade Member Author Offline Ask The Trades Posts: 8815 Total Thanks: 109 For This Post: 0 Braunton, North Devon United Kingdom Gender: Trade: Electrician	Re: Shower problem. Reply #12 - Sep 14^th, 2011, 9:04pm Does it do it with just the hot open, or just the cold open, or only when both are open?
Back to top	Need to post a picture? Click HERE for info! IP Logged

Lectrician

Administrator
Trade Member
Author

Offline

Ask The Trades
Posts: 8815

Total Thanks: 109
For This Post: 0

Braunton, North Devon
United Kingdom
Gender: male

Trade: Electrician

Re: Shower problem.
Reply #13 - Sep 14^th, 2011, 9:11pm

A quick glance at the manual throws up two lines that concern me:

"Hot and cold supply pressure should be balanced"

"If a water supply is fed by gravity then the
supply pressure should be verified to ensure the
conditions of use are appropriate for the valve."

The diagram shows a minimum head from the bottom of the cold water tank feeding the hot water cylinder to the top of the shower head to be 1m - I doubt you can achieve this if the shower head is on a wall, and water tank is sat above the cylinder in a cupboard?

Going by the diagram for a gravity fed system, your cold feed to the mixer must be from the same cold tank the feeds the cylinder. This is what will then provide equal pressure (although still a minimium of 1m head required for both to provide adequate pressure).

Back to top

« Last Edit: Sep 14^th, 2011, 9:15pm by Lectrician »

Need to post a picture? Click HERE for info!

IP Logged

m

GDPR opt-out

Total Thanks: 109
For This Post: 0

Re: Shower problem.
Reply #14 - Sep 14^th, 2011, 9:21pm

Lectrician wrote on Sep 14^th, 2011, 9:11pm:

A quick glance at the manual throws up two lines that concern me:

"Hot and cold supply pressure should be balanced"

"If a water supply is fed by gravity then the
supply pressure should be verified to ensure the
conditions of use are appropriate for the valve."

The diagram shows a minimum head from the bottom of the cold water tank feeding the hot water cylinder to the top of the shower head to be 1m - I doubt you can achieve this if the shower head is on a wall, and water tank is sat above the cylinder in a cupboard?

Going by the diagram for a gravity fed system, your cold feed to the mixer must be from the same cold tank the feeds the cylinder. This is what will then provide equal pressure (although still a minimium of 1m head required for both to provide adequate pressure).

I think you have hit the nail on the head Lectrician, a reduction valve looks like the answer. Thanks M.

Back to top

IP Logged

greg GDPR opt-out Total Thanks: 109 For This Post: 0	Re: Shower problem. Reply #15 - Sep 25^th, 2011, 4:44pm Quote: .... except the header tank is about a foot above the hot tank in the same cupboard in the back bedroom and not in the loft. How high is the header tank in relation to the shower head?
Back to top	IP Logged