Shower Temp Question

[PaulGoddard]

Hi,

Please accept my apologies if this has been asked before, I've searched but could not find anything similar to my specific symptoms.

My setup:
- Moved into house 6 months ago, all setup below is as it was when we moved in.
- Gravity fed water system. Cold tank in loft, hot water tank in upstairs cupboard.
- Mixer shower, not sure of make/model, as despite taking apart as much as I can, parts are not branded.
- External pump = Showermate Stuart Turner 1.4bar twin pump, part number 46202
- Hot water thermostat set to 60c
- Temperature when taken from hot tap of sink next to shower confirms hot water temperature is indeed 60c

My Problem:
- When shower mixed is set fully to its hottest setting, the water temperature only reaches 33c. This makes for not a very hot shower, and a very unhappy wife.

My basic investigation:
1) If I turn the hot water temperature up very high indeed. EG 70c +, then the output from the show rises slightly to a more acceptable level for the wife, but costs me $$$ in heating the water and makes the taps too dangerous for children to scold themselves on.
2) The input pipes to the pump have the types of values on them that can be closed with a flat head screwdriver. If I close the cold value completely, the output temperature of the shower (set to max temp) goes up significantly to 55c. But I only did this as a test, fearing it could break the pump.

We've lived with this too long and I'm now keen to sort the issue.
EG get the same temperature out of the shower when set to the hottest setting as I am heating my hot water tank to.

My questions are:
1) Does this sound like a fault with the pump or the mixer shower?
2) Is it realistic to expect the temperature out of the shower on its maximum setting to the broadly similar to that of the water out of my hot tap? (EG does the pump need to mix in some cold for it to work?)
3) Would it damage my pump if I reduce the input flow of cold water by partially shutting the valve, as a simply way to fix the problem?

Thank you very much in advance for any help people might be able to give. It is very much appreciated.

Paul.

 

[Madrab]

Sounds awful like the thermostat on the shower needs looked at 1st.

 

[oldbuffer]

Hard to be sure without knowing more, but I'd start eliminating as follows (assuming shower is a thermostatic mixer):

1. Shower likely to have non-return valves and filters in hot inlet and cold inlet. Dismantle as far as necessary to get at these and make sure filters are clean and valves not jammed.

2. Most thermostatic mixers have output temperature adjustment, normally set to 38 but can be overridden by pressing a button for hotter temperature. Make sure maximum temperature hasn't been set too low. If you haven't got the instructions make notes / take pictures to make sure you can put things back as they were.

 

[PaulGoddard]

Thanks for the replies.
Sounds like the next step is to get in and carefully dismantle the mixer tap then (having turned off the water).

Not sure it helps much, but I've uploaded some photos.
(Could not get them the right orientation, as they looked the right way up on my PC prior to uploading?)

Thanks,

Paul.


View media item 88517View media item 88518 View media item 88519 View media item 88520 View media item 88521 View media item 88522 View media item 88523 View media item 88524 View media item 88525

 

[PaulGoddard]

I've been looking a bit further a terminology to describe what we have.
From what I can figure out, what we have is called a "concealed mixer with 2 way diverter".
It has two leavers.
The top one controls flow, and when pushed to the right water comes out of the shower, and to the left it comes out of the bath.
The bottom leave controls the temperature.

I'm to try taking the leavers off, then the back plate, to see if I can access the mixer mechanism behind. Hoping it might have some make/model number on it.

 

[PaulGoddard]

Here is a few more photos of the front of the mixer unit.
View media item 88539 View media item 88540 View media item 88541