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Discuss Advice on Hot/Cold bath mixer in the Bathrooms, Showers and Wetrooms area at

  1. AlexTeslin

    AlexTeslin New Member

    Hi All,

    I am a resident of council flat in a 4 story block. Last week my local council has started a work on regeneration program, which includes kitchen and bathroom improvement. To cut the story short, they've installed a new bath with the new bath/shower mixer. And this is where the problem is.

    When I run hot and cold using a bath only tap the water flows just fine. And the cold water has more pressure than the hot. But when I then pull the switch, or whatever it's called, to direct the water to the shower hose, only the hot water flows from the shower head. No cold is flowing at all. Hence the pressure is very low and there is no way to regulate the temperature.

    I asked the plumber who installed the tap and he said to me that he can come back for a private work and install a pump to make my shower work correctly.

    I went to my local bath/shower shop, as I thought there is something wrong in the setup as there was no cold water whatsoever, for an advice. The shop assistant told me that it's difficult to suggest but it looks as either the pipes are not wide enough or something wrong with pipes in general.

    He also told me that I can't install a pump as I have a new combi boiler and no water tanks.

    Can anyone please suggest, if this has to do with pipes and in which case I have to ask the council plumber to fix the problem? Or should I wait until the work is done and call him back to install the pump? But then can I install the pump for the combi setup?

    In fact if anyone can suggest what solutions have I got or what needs to be done?

    Thank you,
  2. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    So you have a combi boiler (mains pressure hot water) no cylinder etc

    If yes then you should have cold water coming out of the shower

    Turn the shower to fully cold (eg the lowest temp) does any water come out from the shower head and is it cold ?
  3. AlexTeslin

    AlexTeslin New Member

  4. AlexTeslin

    AlexTeslin New Member

    Hi Shaun, thank you for your reply.

    I've turned cold water tap only and the cold water came out, yes.
  5. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    At full height et out the shower head as high as possible?
  6. AlexTeslin

    AlexTeslin New Member

    It's fine, I raised the head as high as possible - no pressure difference.

    What I've noticed though is when i then turned hot water tap, the hot water came. When I then turned cold water tap off the water pressure has increased slightly, with only hot water. Why? I expected the water pressure decrease after turning cold off.
  7. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    TBH you should (near enough) have the same hot pressure as the cold

    I would put the fault down to a cheap tap / mixer

    I would phone the council up and tell them something is wrong as it was ok before the alterations
    • Agree Agree x 1
  8. AlexTeslin

    AlexTeslin New Member

    You think there is nothing wrong with pipes under my bath?

    And can you please suggest whether I can use a pump in my combi setup?
  9. snowhead

    snowhead Well-Known Member

    Ring the Council First thing tomorrow.
    You shouldn't have to pay anyone, or wait for a fix.

    When you turn on the Hot , it should be Hot.
    When you turn on the Cold it should be cold.
    When you mix the water with both taps it should vary from cold through warm to hot, depending on the mixer setting.

    Having only Hot coming out of the shower is not good, in fact it's worse than that.
    • Agree Agree x 1
  10. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Did you have a shower before/ if not did the taps work etc

    And no it won't work / not allowed
  11. AlexTeslin

    AlexTeslin New Member

    No, when I moved in I didn't have a shower. So I installed my old shower myself by plugin in the push-fit shower mixer. And I had the same problem then, but I was waiting for the new bath and kitchen from the council and was hoping that the problem will be solved with the new setup. So in short, yes, i had the same problem with my old setup.
  12. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    That is very strange but tbh not your problem as your renting it's upto the council they shouldn't install a pump on a combi system
  13. AlexTeslin

    AlexTeslin New Member

    Ok, so pumps can't be installed with the combi boiler - that's what I thought. Even though I still have no idea why this is the case but one thing I know that I should have a cold and hot water running together in my shower, right? Will call the council first thing in the morning, but I already spoke to them and they are hesitant of fixing it. Anyway, thank you for your replies and suggestions.
  14. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Correct and it's a health hazard as you can't wash ;)
  15. AlexTeslin

    AlexTeslin New Member

    Well, I had another plumber from the council and he said that my cold pipe in the bathroom is not coming from the boiler but from the tank. Only kitchen pipe is coming from the boiler. So that's explains now I suppose.

    So asked the question what can be done to resolve the issue, could I install a pump if there is a tank. He said I still can't install the pump because the pump will produce too much pressure and I will get only the cold water in the shower and not hot. So it's the opposite with cold/hot.

    The only solution he suggested was to add the new pipe for the cold water from the kitchen to the shower, which will produce the same flow. Then I could mix cold and hot.

    It would have been nice to have a pump and have a very strong shower, but still, it will be better than before.
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