Changing a thermostatic cartridge in my concealed shower valve

[Yukster]

My thermostatic cartridge in my Crosswater shower valve (handles, two outlets) need changing. It has been playing silly buggers for a couple of weeks when I couldn't get the water to go hotter although in other taps the hit water is very hot. Today it developed a leak and I found the part number on my faulty cartridge to ensure that I get the right spare part.

What I could use help with is how to open the cartridge clamp nut that is holding the therm (bottom) cartridge in situ. I looked at the Crosswater downloadable maintenance pdf and it says 'remove the cartridge clamp nut'. The trouble is I don't know how to do it! Do I need a special tool for it?

 

[RandomGrinch]

Hi,

From what I can gather, all the parts are listed here:
https://www.showerspares.com/crossw...er-totti-thermostatic-shower-valve-2007-2013/



What is holding you up, is part 11, the 'thermo collar'



This needs unscrewing first, using some adjustable grips (and some cloth for protecting the surface).

Once tht is removed, you should be able to reach part 9, the 'retaining nut'



Which you can undo with a 38mm spanner.

I hope that makes sense and helps!

 

[Yukster]

Hi,

From what I can gather, all the parts are listed here:
https://www.showerspares.com/crossw...er-totti-thermostatic-shower-valve-2007-2013/

View attachment 249721

What is holding you up, is part 11, the 'thermo collar'

View attachment 249718

This needs unscrewing first, using some adjustable grips (and some cloth for protecting the surface).

Once tht is removed, you should be able to reach part 9, the 'retaining nut'

View attachment 249719

Which you can undo with a 38mm spanner.

I hope that makes sense and helps!

Now that you pointed this out it's obvious. But as you can see from the pic above, the dumbass who installed the shower valve set it too deep so the thermo collar is hard to access as it's not proud of the tiles. It's also set in cement. So after carefully chiseling the cement, how do I grab the collar from the front without bending it? I thought I might use two long nose pliers at 6 and 12 o'clock but I'm not sure if that's a good idea

 

[RandomGrinch]

Yes, I'm sorry, it does look quite well set back!

I would possibly try turning it with some pliers from the inside.
You could also try some penetrating oil on the threads?

Theoretically it shouldn't have been wound on very tightly in the first place!

But really thinking outside of the box, do you have something like a rubber watch strap, that can be wrapped tightly around the outside and assist turning it?

 

[Yukster]

Yes, I'm sorry, it does look quite well set back!

I would possibly try turning it with some pliers from the inside.
You could also try some penetrating oil on the threads?

Theoretically it shouldn't have been wound on very tightly in the first place!

But really thinking outside of the box, do you have something like a rubber watch strap, that can be wrapped tightly around the outside and assist turning it?

Rubber strap is a good idea, I'll see if I can find someone like that. What penetrating oil can I use? Is WD-40 a no no?

 

[Diyisfun]

Rubber strap is a good idea, I'll see if I can find someone like that. What penetrating oil can I use? If WD-40 a no no?

Rubber strap..use elastic band

 

[RandomGrinch]

Rubber strap is a good idea, I'll see if I can find someone like that. What penetrating oil can I use? Is WD-40 a no no?

The usual WD40 isn't a penetrating oil.
A specialist version is available, but it's expensive for a single use:

https://www.toolstation.com/wd-40-specialist-fast-release-penetrant/p20970

Apparently, a mix of vegetable oil and 10% acetone, can do a pretty good job too!

 

[Yukster]

The usual WD40 isn't a penetrating oil.
A specialist version is available, but it's expensive for a single use:

https://www.toolstation.com/wd-40-specialist-fast-release-penetrant/p20970

Apparently, a mix of vegetable oil and 10% acetone, can do a pretty good job too!

Once I removed the cement the collar unscrewed pretty easily with a long nose pliers. Unfortunately, there is not enough room to use a spanner so my options are to use a grinder to extend the opening or get a 38mm socket to unscrew the retaining but. But that is expensive to buy for a single use

 

[kidgreen61]

Long socket/ box spanner of the correct size.

 

[Yukster]

Long socket/ box spanner of the correct size.

I haven't managed to find a 38mm box spanner. Screwfix or Toolstation don't seem to sell it. And I'd rather buy locally as I need to fix my shower asap! Arrrgggg

 

[polesapart]

38mm to 1/2" socket from any decent motor parts shop. or £8-9 on ebay

 

[RandomGrinch]

I'm just wondering, if with a suitable bribe/deposit, you could borrow one from a local garage?

 

[Yukster]

I'm just wondering, if with a suitable bribe/deposit, you could borrow one from a local garage?

I can try

 

[Yukster]

The thermostatic valve I found is described as a Crosswater part but when I search for the part number on the website, it finds the Hudson Reed part which is roughly half the price. Anyone here knows if there's a difference in quality between the two original and third party parts?

 

[polesapart]

Probably made in the same factory on the same production line.