Replacing a shower valve body from the back question

[Jsmallberries]

Around 2016 I rebuilt my tiled stall shower and installed a Grohe valve body 30015 with cartridge 47678 and a Concetto shower handle. Thought I was done

A few years later, the mixing valve started failing, where to have an even hot cold mix, the handle was barely moved. If it was put in the middle, the water was too hot. Last year I finally decided to replace it. Grohe sent a replacement free of charge. 11 months later the valve started leaking. Need another cartridge/valve in less than a year. Now 3 in 7 years.

I've had bad luck with this set up, plus the brushed nickel handle and escutcheon plate is faded and weathered looking. This happened within the first couple of years too. They also designed this particular valve body where the shut off stops are blocked by the ears on the valve body. Are their products just bad or did I just luck out with a lemon, discontinued POS?

I can remove the drywall from a bedroom behind the shower. How hard would it be to replace this from the back.?

What is a reliable replacement?

Other shower has a Moen Posi Temp, replaced the cartridge once on 20 years.

 

[Jeff H Young]

I would say its pretty much never fun but be generous on a good size hole! you cut the hot , cold and shower riser 3 couplings and 2 90s it might be a piece of cake .

BTW, I dont have a lot of service experiance with grohe most valves give decades of service moen , delta or pfister, run a long time I hear some rag on Kohler and grohe dont go with internet no name brand stuff my opinion

 

[Sponsor]

 

[Breplum]

You got unlucky. Grohe has a more-or-LESS lifetime warranty. So ask for free replacement parts.
I've got at least a hundred of the basic cartridges installed on all varieties of bathrooms and never think twice about using old Grohe. Now that Grohe sold to Lixil and no longer has local reps, I am not a fanboy any longer. But the old cartridge 47678 stuff is fine.

 

[Jsmallberries]

Thanks,

I'm trying to shame them into a free replacement, leaking in less than a year? Really
Soft water too. They are pushing back wanting a receipt, bought online 2016? Last year they just asked for a picture. I was able to find the emails from last August. Sent those

Hoping this works, I'll go with one last replacement before attempting a change out

 

[Jeff H Young]

if its junk get rid of it not worth going through it again

 

[John Gayewski]

I can't remember what grohe valve body it was but I remember it being poorly designed with the stops blocked. My opinion is go with what works. Has grohe worked for you? If not make a change. We like delta.

 

[Jsmallberries]

So they’re sending a free replacement
I’ll give it one more shot. Next time I’ll change out the valve body.

And yes, poor design, where part of the valve blocks the shut off stops.
I asked a GROHE rep about it, their response was”

one of the quirks of this particular valve and the supervisor said using a thinner screwdriver should help

nope, too thin would make it harder to turn and strip out the slot.

 

[Jeff H Young]

now i remember those dumbass valves lol the ears in front of the screws German engineering ha ha

 

[Jsmallberries]

09 2026 leaking again, jeez, 4th time in 10 years, requested free replacement again, if not free, going to open up the wall and replace the whole thing......again

Maybe just a bad design and a one off, but never again with Grohe, not cheap either

 

[Jsmallberries]

09 2026 leaking again, jeez, 4th time in 10 years, requested free replacement again, if not free, going to open up the wall and replace the whole thing......again

Maybe just a bad design and a one off, but never again with Grohe, not cheap either

 

[Jsmallberries]

If I do replace the rough in valve, any suggestions to make it easier? See photos from the 2015 install with Grohe below

If I replace the whole thing, I might add a separate hand held. I just did the other bathroom with this Delta Monitor® 14 Series Shower with Raincan, Hand Shower & Rough Valve in Champagne Bronze
Very happy with it so far

Drywall accessible from the back

 

[Sylvan]

I would say its pretty much never fun but be generous on a good size hole! you cut the hot , cold and shower riser 3 couplings and 2 90s it might be a piece of cake .

BTW, I dont have a lot of service experiance with grohe most valves give decades of service moen , delta or pfister, run a long time I hear some rag on Kohler and grohe dont go with internet no name brand stuff my opinion

I will NOT repair or install any Kohler product.

I will replace Kohler with Delta, Moen, and Pfister in that order, as I love having peace of mind for decades with these products.

I noticed the words "Bold look" BUT never Quality " mentioned, IMHO

 

[Sylvan]

I would say its pretty much never fun but be generous on a good size hole! you cut the hot , cold and shower riser 3 couplings and 2 90s it might be a piece of cake .

BTW, I dont have a lot of service experiance with grohe most valves give decades of service moen , delta or pfister, run a long time I hear some rag on Kohler and grohe dont go with internet no name brand stuff my opinion

I will NOT repair or install any Kohler product.

I will replace Kohler with Delta, Moen, and Pfister in that order, as I love having peace of mind for decades with these products.

I noticed the words "Bold look" BUT never Quality " mentioned, IMHO

 

[Jsmallberries]

Should be able to do this from the back and use copper slip couplings to reattach new valve body, correct?
Going to go with Delta

 

[Jeff H Young]

Delta is good yes shoud be easy from the back . sometimes slip couplings are easier than ones with stops as you seemed to be mentioning

 

[Rim Country Plumbing Co.]

Plumber here (Rim Country Plumbing Co., Payson AZ). Back-side valve swaps are one of the nicer jobs when the drywall is accessible — a few things from doing these:

- Cut the access hole bigger than you think you need. You want room for two wrenches on every joint, and you'll thank yourself when you're sweating the last coupling.
- Copper repair couplings (the no-stop/slip type) are the right call, like you figured. Mark your insertion depth with a Sharpie before you slide them on — in a tight wall cavity it's easy to push one too far and starve the joint.
- Before you close the wall: pressure-test everything, leave it pressurized overnight if you can, and take photos of the new valve location for the next person.
- While it's open, replace the shower arm and check the tub spout/diverter. And look for old water damage on the framing — a slow drip from that Grohe could have been feeding mold for years.
- Delta MultiChoice is a solid pick. The universal rough-in means if you ever want to change trim styles down the road, you won't be opening the wall again.

 

[KlamathFallsPlumbing]

Since you're going in from the back, cut the access opening generously - you'll want room to work a torch or press tool around the valve. Slip couplings on the copper make the swap much easier in a tight space, and add blocking between the studs to mount the new Delta valve solidly so it doesn't stress the connections. Snap a photo of the old piping layout before you cut anything, and consider a valve with integral stops so the next cartridge change doesn't need a whole-house shutoff.