Replacing bath & shower mixer bar

7 Apr 2015
Reaction score
United Kingdom

I had a plumber come and replace a bath & shower mixer at short notice as it started shooting water all over the bathroom.

Unfortunately he did a really bad job with the installation. A couple of rubber washers were missing from the mixer bar package and he 'improvised' with some cheap silicone sealant around the top (where the bar connects to the pipes on top of the bath), which then leaked. I had to add loads more silicone to make it water tight, but it looks really messy and is starting to get black mould. Also, the mixer bar seems to be failing as the shower doesnt get as hot as it should.

So, I would like to replace it and do it myself.
The mixer bar looks like this one, except it had a kit to allow mounting on top of the bath:

What I am wondering is, are there water tight washers I could buy for underneath, and what kind of tools will I need? Large adjustable wrench?

I know how to turn off the water.
It would be great to know how to do this in case hard water kills any more mixer bars in future. I'm thinking about getting a water softener installed eventually.

Sponsored Links
How old is the mixer?

Thing is you can purchase washers for the shower tap valves, no need for silicon, if the shower came incomplete it should have been taken back.

If the water is not heating correctly are you sure the plumber connected the pipes correctly?
Was this installed recently or quite some time ago?

Either way, the manufacturer should have an MI, which will detail the parts included in the installation. Find the details of the rubber washers you are missing and that will be a start.

I assume you mean it is leaking down from the mixer valve under the bath, through the holes designed for taps?

In which case, you will need the washers that are needed to seat under the tap before it seats on the bath, you will then be able to tighten up the backnut using a crows foot basin wrench, probably 3/4" being that it's a bath attachment.
Thanks, good specific info there.

I dont have the packaging from the mixer and after googling a bit it seems to be discontinued. These products seem to endlessly rinse and repeat so it's impossible to service them. But yes, the leak was around the bath tap holes so I guess they should be standard. Will see if I can measure to check if its a 3/4 wrench I definitely need.
Sponsored Links
You can get backnut and washer sets on ebay and all sorts of places.

Just check that it's 3/4" inlets, which they should be if it's for the bath.

If you are buying a new tap, it should come with it though.

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local