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Discuss Hot Water not running to new shower - New Bathroom Renovation! in the Bathrooms, Showers and Wetrooms area at

  1. Ciel

    Ciel New Member


    I recently had my bathroom renovated, and all seemed well at first (apart from the electrical outlets, but that'll be sorted soon, I hope).

    I had this shower put in:

    Aquarius Dunbar Thermostatic Period Shower Valve & Traditional Head With Fixed Rail Kit 13108 | UK Bathroom Store

    There was a minor issue where the fitter/plumber had mixed up the cold and hot water pipes, so the indicators he put it were incorrect, but I saw that as a non-issue, as long as it worked one way or another.

    When I first used it, I noticed the shower was either fully hot, or fully cold - I would have to turn the temperature knob/dial fully one or another for any temperature change to happen. And as I said, it would change from boiling hot, to freezing.

    I thought this might be an issue, but I decided to change the temperature on the boiler instead, and leave it running on its max temperature.

    Now, though, there is no hot water running to the shower, no matter which way I turn the thermometer dial. The boiler just doesn't kick in to indicate it's heating water. The boiler is still running hot water to the taps in the bathroom and kitchen, and radiators throughout the house, so I have no idea what's going on.

    The bathroom was renovated 2 days ago, and I've just sent a text to the plumber. But what could be causing this issue? Previously, why was the temperature either just fully hot or fully cold? I thought this thermostatic shower valve was meant to mix the water... And now, where is there no hot water coming out at all?
  2. YorkshireDave

    YorkshireDave Plumber

    We may have ideas as to why here, such as being piped backwards, but really your first port of call must be the plumber then, possibly, Aqualisa tech support, who will have a much better idea of what causing your symptoms.
    • Agree Agree x 1
  3. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    I’d say Piped wrong
    • Like Like x 1
  4. bogrodder

    bogrodder Plumber GSR

    Filters blocked?
  5. Ciel

    Ciel New Member


    I'll certainly be getting the plumber out next week to sort this out.

    Do you know if all plumbers are required to sort out their plumbing issues within a certain time? What I mean this, is there a guarantee period on works?

    Also, can you explain to me how the piping being backwards could cause this no mixing of water, then altogether no hot water at all?
  6. Ciel

    Ciel New Member

    It's a new shower - is this likely?
  7. Ciel

    Ciel New Member

    Can you explain how the piping being wrong can cause this? The hot came at first, though it didn't mix with the cold water, then it stopped altogether..
  8. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    Because there is a thermostatic cartridge in there probably that only works with hot coming in one way
    • Agree Agree x 2
  9. Ben-gee

    Ben-gee Plumber Top Contributor!!

    The thermostatic shower cartridge closes the cold inlet if it’s too cold and it closes the hot inlet if it’s too hot.
    If YOUR shower gets to hot it closes the cold, so gets hotter so shuts down altogether as fail safe.
    Most have to be plumbed the correct way around - sometimes the cartridge can be reversed but I’m not familiar with your particular one.
    Simplest solution is to cross the hot/cold shower feeds at some point to correct them.
    • Agree Agree x 2
  10. Ric2013

    Ric2013 Plumber

    I can't really understand why it worked one way at first and now works another way but, as the others have explained, you can't just reverse the hot and cold on a thermostatic mixer unless the manufacturer has made specific provision for this.

    As far a guarantee goes, the work will be covered by the Consumer Rights Act.

    If the reversed pipework was your plumber's fault and not your fault, then it would be reasonable to expect the plumber to rectify this as the plumber presumably told you it would work like this and it doesn't and you have to give him an opportunity to make good. Unless, of course, he can show that the manufacturer states reversed pipes are okay.

    However, you've possibly made it slightly more complicated if you supplied the shower yourself. If the shower is correctly replumbed and you still have problems, is the fault inherent in your shower, or has the reversed pipework damaged it? If the plumber supplied the shower, then, at this point, he must replace or repair, but if you supplied it you may find yourself stuck between a plumber who thinks the shower is defective and UKbathroomstore who may think the plumber broked it.
  11. Ciel

    Ciel New Member

    I did supply the shower myself, as it would have been £100 less..

    Is it likely the reverse pipework would have damaged anything inside it? Surely if it was defective, it wouldn't have supplied hot water at all at first?
  12. Ciel

    Ciel New Member

    Is it possible that this cartridge is now damaged? If it shut itself down, can it be reopened and reused, or would a new one have to be purchased?
  13. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    Contact manufacturer
    • Agree Agree x 1
  14. bogrodder

    bogrodder Plumber GSR

    Yes, could be loose bits of sealant, wood shavings, brick dust etc. All depends how clean the installer was, find where they are and check them
  15. Ben-gee

    Ben-gee Plumber Top Contributor!!

    Buying things yourself to save money means you now have to deal with that and really ought to pay for any time the plumber has to take to refit (should it turn out the shower is faulty). Suddenly you’ll wish you hadn’t “saved” that £100, we may have to pay a bit more than internet - but this gets us loyal and quick redress from our local suppliers in cases such as this.
    Having said all that in your particular case I don’t see any excuse for piping up the wrong way around and just leaving it like that when this is discovered.
    • Like Like x 2
    • Agree Agree x 1
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