Our main bathroom shower isn’t mixing the hot and cold water any more, its just luke warm. We’ve spoken to loads of plumbers and none are available till after Christmas, but we’ve got a bunch of family over for a week next Monday!

So, here are a couple of photos of the offending mixer.

The plumbers we’ve spoken to suggest its the thermostatic valve. Does anyone recognise this and can name its make?

The added complications are:

1) The entire bath is tiled so we can’t easily access the isolation valves without chipping away and removing some tiles.
2) There’s no name or model anywhere that we can use to ring round the plumbing merchants to try and source a replacement part.

Any ideas on how to fix this? Emergency mixer shower thingy on the bath taps?

Turn the water off at the main stop cock , take off the shiwer by undoing the 3 nuts, take it to a plumbers merchants and they should be able to give yiu a new unit that fits, or replace the thermostatic unit thats inside, its a case of pulling the sealed unit out and replacing it with a new one,

easygirl, the three nuts being the two water ones and the small grub screw at the back?

If the centre to centre of the pipes is 6″ then you should be OK just to fit a replacement
Where are you based?
I am a plumber

Turning off your mains water won’t really help unless you are on a combi or unvented.

So am I right in thinking you don’r get enough hot water through the valve?

If so it could be the thermostat or it could be a dirty / blocked strainer on the inlet hot water side.

Isolate water, remove cartridge from valve body look fro mesh type filters, or look in inlet elbows for mesh or cartridge type.

Check the water is hot going to the shower on the elbows. How scaled is the water with you? Could be the thermostat is scaled or the movement which adjusts is sticking. You ‘should’ be able to unscrew the face and the stat and valve should come away. Clean and descale and then rebuild with plumbers silicon grease. Just done mine, although slightly different, principles should be the same. Oh and turn the water of first !! The grub screw just holds the mixer to the baseplate which is screwed to the wall.

Looking at the picture it ‘should’ unscrew just in front of the elbows.

I have similar symptoms – although my mixer is much more integrated into the tiles than your model – removing that looks simple.

For now I’ve just reduced the flow through the main stopcock – I reckon they forgot to fit a flow restrictor in the cold side.

If you turn on a couple of other cold taps and the shower runs hot then this could be your issue too.

1) The entire bath is tiled so we can’t easily access the isolation valves without chipping away and removing some tiles.

That’s the big problem. If you’ve got a hot water cylinder and cold tank in the attic you may be reduced to turning off the boiler, draining the cold tank in the attic (which should feed the hot water cylinder and the cold tap) and draining the hot water cylinder. To do this turn off the feed to the cold tank or tie up the ball valve and turn on the hot and cold taps.

If you end up getting a plumber in, get some isolation valves where you can get at them even if it’s in the attic or under the carpet in the hall (depending on where the pipes run).

soops a plumber!! rolls around on floor holding stomach 😀
actually he is, just needs to turn up now & then.

If you tie up the ball valve in the cold water tank and then drain completely via the cold taps, when you open the hot taps you will only lose a few litres from the hot water tank, which is really handy if its already hot and you don’t want to waste it 🙂 The cold water tank feeds into the bottom of the cylinder so without the head of water, the cylinder cannot empty.

There should be an isolation valve somewhere downstream of the cylinder.

So, we are on a Combi system so the water is heated on demand.
The left hand elbow gets hot when it is on but only a tiny amount of the water is mixing so the shower output is slightly warmer than bloody freezing.

I’ve eyeball measured the distance between the elbows at about 130mm, but from watching this video: http://www.youtube.com/watch?v=W60cYIzokec it lookslike I might not have to take it off at the elbows, which is what I thought I’d have to do!

We are in Norwich and the water is very hard, lots of limescale.

The trouble is, there are probably tens of thousands of different cartridges!?

I’m sorry if I’m wrong, but I *think* you can take out the thermostatic valve, and run it as a normal mixer tap? Worth considering if you’re desperate? It won’t maintain a constant temperature, but will allow for hot showers at least.

I asked my shower makers for a service kit as the tap was getting very stiff. They wanted £130 for one 😯

Thats why I stripped, cleaned ( although I have a water softener, the brass had gone a bit green on the threads) and rebuilt. If you are on a panic. Measure beween the centres on the mixer and just get a new mixer to mount to the wall. If you are unsure on what you have and xmas round the corner, maybe the quickest, albeit a bit more pricier way of doing it.

So, I’ve figured out how to strip it down somewhat. But I’m stuck now and a part appears to be broken.

Then once I’d wiggled off the broken plastic part, this is what I’m faced with/

Would removing the circlip allow the final section to slide off the spindle? hmmm

Circlip off, the thermostatic unit should be behind it, make sure water is off

exactly the issue I had last week. Find the model of the shower then do a You Tube search, probably this one as the parts and shower look like the one I found a video of (edit: not that shower, but the internals look the same):

[video]http://www.youtube.com/watch?v=1QoIYPG4IMA[/video]

Didn’t take me long (although there was a butt clenching moment when I thought the shower would break before I took out the cartridge) Just, as everyone else has said, isolate the water supply, and don’t worry when you take the cartridge out that water starts pouring out. Also, wear gloves to handle the cartridge if you can, I found out the hard way just how sharp brass threads are, I slashed up my fingers and thumb real good.

The cage that pushed against the spring had broken a prong and I think that had become jammed. Cleaned it all, put it back together (minus one prong) and it seems to work ok at the moment, will replace the thermostat and whatnot after xmas.

AND PUT THE PLUG IN!!!!!

You’d be amazed what you can lose down the plughole

dirty / blocked strainer on the inlet hot water side

I’m betting on this, at the inlet to the pump (assuming its pumped) though it’s less common for the scale to be in the hot side it could be something else.

listen to Bear, he knows his stuff.

Bollox Bollox Bollox! The Stop cock has seized and the god damn useless plumbers that tiled in the bath have not put in isolation valves!
I’m trying to contact the old owners via the Agents to see if they know whether any isolation valves were put in and if so where.

Any tips how to unseize the stop cock? I’ve given it a blast of GT85! It’s an old Victorian house and the tap is about 8″ down with little room to use anything to get leverage on it.

have you taken the side panel off the bath? or is that where the tiles are too?

isolation for our shower was all under there – the pipes were only in the wall after they went past the top of the bath. If the pipes come down from the ceiling have a look in the loft.

I’d be wary about putting too much force through the stop cock tap – it would be a bad thing if it broke. You could try one of those pipe freeze kits though?