Removing internally screwed thermostatic cartridge

Saruman

Hopefully someone can help.

My shower thermostatic cartridge failed. It only delivered hot water, not cold.
Unfortunately taking it out to replace has turned in to a bit of an ordeal.

If you look at the attached pictures, the one called plumbing.jpg shows what I'm looking at right now.
Then look at Thermostatic-Shower-Cartridge.jpg
The piece on the right of that image is what I could remove. It's only part of the whole cartridge (M12HJ8). Clearly there's a design fault in them because when you buy a new one, the website tells you that because both pieces unscrew the same way (anti clockwise) the internal piece can sometimes come out and leave the larger cartridge behind.
"The cartridge will unscrew from the valve anti-clockwise. Unfortunately the top piece unscrews from the cartridge anti-clockwise, therefore if the entire cartridge is seized in the valve with limescale, it might need more force to unscrew than the top piece, thus the separation of the parts."

so looking back at plumbing.jpg you can see I need to remove an internally screwed in nipple.

As far as I can tell, I need an internal pipe wrench to remove it, something I can't seem to find for sale in Ireland.

I did cut in to the internal piece and try wedging items in there to turn it but I haven't manage to find a piece of metal that's the right size or strong enough to do the job. Everything I have is either too big or too small.

It might be easier to get the internal pipe wrench but just checking here if anyone knows that this is the correct tool and if there are any shops in Ireland, ideally Dublin 15 or Dublin 11 that sells them?

sullzz

Saruman wrote: »

Hopefully someone can help.

My shower thermostatic cartridge failed. It only delivered hot water, not cold.
Unfortunately taking it out to replace has turned in to a bit of an ordeal.

If you look at the attached pictures, the one called plumbing.jpg shows what I'm looking at right now.
Then look at Thermostatic-Shower-Cartridge.jpg
The piece on the right of that image is what I could remove. It's only part of the whole cartridge (M12HJ8). Clearly there's a design fault in them because when you buy a new one, the website tells you that because both pieces unscrew the same way (anti clockwise) the internal piece can sometimes come out and leave the larger cartridge behind.
"The cartridge will unscrew from the valve anti-clockwise. Unfortunately the top piece unscrews from the cartridge anti-clockwise, therefore if the entire cartridge is seized in the valve with limescale, it might need more force to unscrew than the top piece, thus the separation of the parts."

so looking back at plumbing.jpg you can see I need to remove an internally screwed in nipple.

As far as I can tell, I need an internal pipe wrench to remove it, something I can't seem to find for sale in Ireland.

I did cut in to the internal piece and try wedging items in there to turn it but I haven't manage to find a piece of metal that's the right size or strong enough to do the job. Everything I have is either too big or too small.

It might be easier to get the internal pipe wrench but just checking here if anyone knows that this is the correct tool and if there are any shops in Ireland, ideally Dublin 15 or Dublin 11 that sells them?

Had a similar issue before, i ended up drilling a hole in the face of the cartridge, heating up around where the thread is with a blowtorch and with a large flat head screwdriver and hammer hit it loose using the screwdriver in the drilled hole.

Saruman

I've tried that but without the heat. Will give that a go thanks.

sullzz

Saruman wrote: »

I've tried that but without the heat. Will give that a go thanks.

The heat is the key, you really need a blow torch and really heat it...... Just be careful not to burn the house down .. that would be too much heat