Plumbing emergency! Shower mixer is stuck and won't shut. How do I uninstall that thing?

Forums › Home Workshop DIY › Plumbing emergency! Shower mixer is stuck and won't shut. How do I uninstall that thing?

PPAP

41 posts

Geek

#185158 11-Nov-2015 23:50

Ok, not quite an emergency now as I found out that I can turn off the inlet valve on the hot water tank and turn the shower mixer to the hot end, it stopped. And I turned the hot water power off. So we can still use the cold water in the house. I think that gives me the chance to fix it by myself rather than call a plumber now.

It's a Methven brand, don't know how old but looks like this. http://www.methven.com/nz/showering/shower-mixers/minimalist-shower-mixer-all-pressure We bought the house 5 month ago and the bath room looks quite new. The Methven installed manual doesn't help much as it might be a different model. http://files.methven.com/nz/installation-sheet/mmhpscp-installation-sheet.pdf

I cannot find a screw or a hidden screw anywhere on the mixer. I did some fix job on the kitchen tap which was very easy. But this time I cannot even remove the top cover. It seems the whole stainless thing is a cylinder shape and that is "maybe" screwed on the brass base.

Any hint or help would be greatly appreciated. Guys.

PPAP

41 posts

Geek

#1426640 11-Nov-2015 23:55

So called 20 year guarantee.

I think that manual might be a different model?

andrewNZ

2487 posts

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#1426641 12-Nov-2015 00:06

Let me tell you from experience, the shower mixer is the last thing you want leaking. I'd be letting a plumber do this one so you have someone to hold responsible if it goes wrong.

I don't know how lng mine was leaking (I'd guess a year or more), but I had to tear the wall open to dry it and kill the mould (my framing was as wet as wood can get, you could run your nail along the timber and squeeze out water). My carpet was rotten and if I had a wooden floor it'd be buggered too.

Insurance doesn't pay out much for gradual damage 1500 less excess in my case, which doesn't come close to paying for the damage.

The manual appears to show a standard cartridge mixer. The cartridge will be cracked.
There will be a grub screw holding the handle on. It'll be underneath. Once you get that off the rest will present itself..

I suspect the handle might be the grub screw in this case, but I could be wrong.

Seriously, get a plumber.

PPAP

41 posts

Geek

#1426643 12-Nov-2015 00:54

Long story short, I fixed it.

Will update tomorrow with new photos.

mattwnz

20153 posts

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#1426645 12-Nov-2015 01:17

I have one of these same models. Think they were released about 2002-3, as I recall getting it when it was recently released. Would be interested in the type of problem you had.

Dingbatt

6756 posts

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Lifetime subscriber

#1426717 12-Nov-2015 08:41

andrewNZ: Let me tell you from experience, the shower mixer is the last thing you want leaking. I'd be letting a plumber do this one so you have someone to hold responsible if it goes wrong.

I don't know how lng mine was leaking (I'd guess a year or more), but I had to tear the wall open to dry it and kill the mould (my framing was as wet as wood can get, you could run your nail along the timber and squeeze out water). My carpet was rotten and if I had a wooden floor it'd be buggered too.

Insurance doesn't pay out much for gradual damage 1500 less excess in my case, which doesn't come close to paying for the damage.

The manual appears to show a standard cartridge mixer. The cartridge will be cracked.
There will be a grub screw holding the handle on. It'll be underneath. Once you get that off the rest will present itself..

I suspect the handle might be the grub screw in this case, but I could be wrong.

Seriously, get a plumber.

The grub screw is visible in the second photo. You are quite right, undo the grub screw, pull the handle housing (called lever handle in diagram) off. Then it's just a matter of unscrewing the round cover at the front of the cartridge housing then undoing the brass retaining ring, pulling out the failed cartridge and replacing it with a a new one.
When I did mine, the handle housing took a little force to get off which had me thinking I was doing something wrong. However, it was plain sailing, as you pointed out, once that was off.

Oh, and needless to say, turn the water off at the mains before starting (I know the OP has resolved his problem, this is for others) and depressurise the pipes using the lowest tap in the house first.

“We’ve arranged a society based on science and technology, in which nobody understands anything about science technology. Carl Sagan 1996

PPAP

41 posts

Geek

#1427046 12-Nov-2015 16:59

If it was more than replace the cart or some kind of easy job, I would call a plumber to get some sort of guarantee. But luckily it turned out to be a fairly easy job.

Yes the handle bar is the grub screw as well. They came out together and the cover still didn't come off at all. That's why I was looking for another locking screw.

There is a white plastic bit, maybe some sort of washer, on the top of the screw hole inside. Last week the handle bar got loose, I removed it and installed back without thinking, too easy. It worked fine for a while, but what I didn't know is that the white plastic bit was not in position, it got loose inside the cover and eventually jammed the movement of the cover last night. So it was a easy fix, just used a tiny screw driver to move the white plastic bit to where it should be. That's it.

What concerns me is that even with the grub screw off, I still cannot remove the cover. It was very very tight, I was worrying about applying too much pulling force would damage something on the back.

Any comment please.