Water leak only when shower is turned on

Hi everyone - new to the forums and in need of help.

We live in a ranch style bongalow with the main bathroom on the main floor. I noticed a considerable amount of water in basement laundry room which is directly under the main bathroom.

I ran a bath and let it drain and there was no leak. I then ran the shower and was met with a steady stream of water coming down into the basement.

The tub itself has a diverter on the main spout and a single turn knob for the hot and cold (in case that makes a difference). Also, we have noticed lately that there's water coming from out of the turn knob but wasn't sure what the cause of this would be and not sure whether the new leak and that existing issue would be related now.

I have zero experience with plumbing and any help in directing my efforts would be greatly appreciated. Thanks so much in advance.

 

#1 Post a picture of the valve.
The leak at that valve is the cause and needs to be addressed ASAP.
With a brand name likely the repair parts would be free for the manufacture.
Brand name on the trim ring?

 

Hi Joecaption,

Sorry, not sure what valve you're asking about. Are you referring to the hot/cold knob that is pushing water?

Again sorry, I literally know nothing about any of this.

 

Picture of the whole thing, no close ups, needed.
Someone here will know the brand name.
Main water supply lines will need to be shut off, handles removed, cartridge removed and replaced.

 

If no leak while running the tub, it rules out drain issues or main diverter issues. If it leaks when the shower is running only, it points to a leak at the shower arm in most cases. That is the small 6 inch curved piece of pipe that goes from the shower head into the wall and is screwed into the plumbing behind the wall. There is a cover plate on that pipe that dresses out the way the hole in the wall looks. Slide that plate forward and look into the hole and see of you can see a drip when the shower is running. Lets rule that out first.

Next joint would be where the riser pipe comes off the valve body. To check that out, remove the shower on/off diverter arm, remove the two screws holding on the large cover plate to see the valve body. Temp. put the handle back on so you can operate the water. Turn on the water, then divert to shower head and look for leaks. One should be apparent at this point and let us know.

 

Do you live in a cold climate and did the house freeze at some point? If so it's common for the pipe in the wall that connects the valve up to the shower head to burst.

 

Hi Joecaption,

Ok, I've taken pic and posted below. I believe the brand is moen but age would probably be close to 20 years old.



Is this a relatively easy fix in your opinion?

Thanks.

 

Hi Pilot Dane,

We do live in a cold climate, winter in Ottawa, ON, Canada, but we had a very mild winter and to the best of my knowledge the house never froze at all. We had some cold days for sure but the leak started during very warm temps.

 

Hi Czizzi,

thanks so much for those recommendations. I'll do my best to trouble shoot the areas you suggested and report back. Do you believe it could be the cartridge in the main valve?

I only bring it up because it does have a noticeable leak at the knob during a shower. Joecaption's reply below seems to suggest that this could be the cause of my leak also. What's your opinion?

Thanks.

 

No access panel on the backside of the shower wall.

 

Hi ct-18,

None unfortunately. The bathroom bathroom is on our main floor and the backside of the shower would be a wall to our kitchen.

If there's an issue behind the wall I'll have to go through the bathroom wall. Unfortunately.

 

You can remove the knob and then the escutcheon plate. Then just stick the knob back on and turn on the water. Without the escutcheon plate you might be able to see into the wall for the source of the leak.

 

I politely disagree. Patching tile would be a bear. If you're lucky in the kitchen you can go through the back of a cabinet. Just put a premade access door when finished. It will be in the cabinet and hidden. Even if no cabinet easier to patch Sheetrock than tile. May not come to that though.

 

I agree with czizzi that the most likely problem is between the valve body and the shower head. I seriously doubt it is a cartridge problem.

I also agree with Ray that patching the kitchen wall will be MUCH easier than patching the tile wall. I detest drywall work but when I replaced my bath/shower valve I came in from the back and then patched the hole. I defy anyone to find where that patch is located.

 

Good news!

After taking the plating off and reattaching the handle and turning on the water, the only leak I could see was clearly coming from the cartridge area. And I mean calling it a leak was an understatement, it was pouring out water.

A quick run to my home improvement shop netted me an official moen replacement. The old part came out easy enough, new part went in simply and the biggest headache was getting the plate back on.

Ran a shower and not a leak to be found.

Thank you so much to everyone for your amazing advice. This seems like the best possible outcome and I'm happy I didn't have to tear down any walls.


cheers and thanks again.

 

Thank you for letting us know the solution. It may help someone else.