Question about Grohe Plumbing

2 Answers

I have no hot water coming out of a shower with a Grohe 2 part control. One controls volume, the other controls temperature. I tried installing a new temp. control valve, but there was no difference. I then removed it and ran the water without the temperature control valve in place and only cold water flowed out. It's in an older home with the possibility of galvanized pipes being clogged, but there is plenty of hot water coming through the sink. The mixing valve is behind a tile wall. Do you have any suggestions before I have to remove some tile?

Posted by on

  • 1 more comment 
  • kbizzarro Sep 09, 2010

    Thanks for your suggestion. I'll give it a try. I just have to figure out how to get that compressed air from my compressor with any pressure into the shower control opening. If I take the control valve out ( which operates the temperature and flow control through an approx. 1 1/2" opening) it will be difficult to seal. I will try sending it back through the shower head supply tube and see if I can get some air pressure to blow back through the sink.

  • kbizzarro Sep 11, 2010

    I tried your suggestion, but unfortunately, it didn't clear the line enough to make a difference. I got some limited blow back through the sink supply tube, but not enough to make a difference after repeatedly trying compression and decompressing the line with 120#s of air pressure. I ended up removing some wall tile and found copper feeds to the mixing valve, but unfortunately I suspect that there may be galvanized pipe in the floor between the sink and shower. Access to this section to verify will involve either ripping out a tile mud floor, or from underside ceiling exposure from a very large formal living room.
    Someone had renovated this bathroom previously, but unfortunately they probably didn't do a complete overhaul of the ancient plumbing. I need Superman with his X-ray vision for this one!

  • kbizzarro Sep 11, 2010

    There is only one exterior on/off water control with a water temperature dial attached to the same arm.
    There is no way to turn only the hot side on by itself. I blew compressed air back through the shower head arm,trying to clear any possible blockage, removed the supply tube under the sink and still pushed back very limited pressure after fully opening the shower control set on 110 degrees ( it's highest dial temp). After opening a wall section, I found copper supply tubes to the shower control valve, but I suspect that they are fed by a galvanized feed after the sink and back to the shower.

×

Ad

2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 905 Answers

Hello,

Your description indicates that it is indeed the mixing valve (tempering valve) that is at issue.

There are a few things that you can try, depending on how far you want to go. By default, the mixing valve will go to "full hot" once it detects water temperature has dropped below its set point. If you have even a trickle of water when turned to full hot, then you may be able to pump a weak acid through the hot water pipe (break apart a union that feeds only the shower), and the acid may clean out the build up. This probably won't work since only the cold side is flowing.

Before removing tile, consider accessing it from the other side of the wall, through plaster / drywall. Once repair is done, hide the access panel using a picture / frame or some other method.

Posted on Sep 10, 2010

  • Sheldon Dedek Sep 12, 2010

    I saw your comments in response to other solutions, and have a suggestion to add to the compressed air idea.

    If there is a restriction in the pipe that runs in the floor, the air may be whistling by it, making noise. If you are able to use a long hose between the compressor and the shower head, you can make it relatively quiet in the bath area.

    When the air is blowing back through the sink, use a "Super Ear" or similar type of amplifier to see if you can trace the flow of air from the sink back to the shower. When you come across a "noisy" area, mark it. Trace back from shower to the sink, and see if the previous marked area is the noisiest spot.

    If it is, that is likely where your obstruction is located. I may not be superman, but with a child's toy, you can have Super-Hearing.

×

Ad
  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Master
  • 43,501 Answers

Hi,
Before removing tile I would shut the hot water off and then open the hot on the sink... then blow compressed air backwards through the hot pipe and see if you can get the dirt to back out...you probably have rust built up in there and maybe if you can blow it back and out the sink it will work for you....
Remember is take the aerator off of the sink so that the **** can come out there....or better yet take the supply tube off at the sink and let the air blow out there so you don't run the risk of plugging the sink faucet up...

heatman101

Posted on Sep 09, 2010

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

I have a Grohe shower system that has the temperature control it was working fine and now the water only comes out luke warm. the handle goes from 65 degrees to 110 degrees. I live in a older highrise...


WEll, the question is do your sinks have water that is hot enough? If no, perhaps your water heater is set too low. If yes, many shower controls have hot limiter and if you pull the handle, often there is a spline assembly that stops the travel from going hot, adjust to allow more.

Dec 13, 2010 | Grohe Home

2 Answers

Final install of handle ,control valve etc.


If you but a trim kit it has the installation instructions for the trim with it. Did you open the stops to let water in?

Jun 28, 2010 | Grohe Integrated 1/2'' Shower Thermostatic...

3 Answers

Install trim and adjust the thermostat on a Grohe shower faucet


Before you install the temperature control knob, adjust the valve body (47111) with a wrench to set the temperature to "100 degree or close to it". Now, place the limit ring to tdc (top dead center) and control knob with the red 100-degree align to it. Your problem may have been the valve's temperature setting is out range when you installing the temperature control knob.

Jun 28, 2010 | Grohe Grohmix Thermostat Valve & Trim -...

1 Answer

I'd like to install 1 shower had and one hand held shower. What do I need to have ?


well you can do a 3 way shower valve , or a mixing valve with 2 control valves. or you can do just to regular shower valves one for each of the heads you want one for the rain and one for the shower head. this way is cheeper and you can have one on hot water and the other cold water or the other way around or both the same temp.

Apr 26, 2010 | Grohe Integrated 1/2'' Shower Thermostatic...

1 Answer

The temperature in my shower is very luke warm only at the shower


Do you mean the other faucets in the house are hot and only the shower is warm? If so there is an anti-scald adjustment on the faucet that needs to be turned up a few notches. Havent adjusted a Grohe faucet but most faucets you rmove the handle and behind the handle is a nothced adjustment ring that prevents the faucet from getting too hot. This ring, or stop, is pulled out and twisted clockwise(or counter clockwise to set higher or lower max temp, then pushed back. maybe you can look up grohe to see which way ring or stop adjusts for hotter water.

Jan 23, 2010 | Grohe Integrated 1/2'' Shower Thermostatic...

2 Answers

I have exactly the same problem


you need to change the cartridge, it is a temp control and is going bad so it keeps you from burning yourself it is like a mixing valve and is givng more cold water, that way you don;t get burned,,

Jun 18, 2009 | Grohe Integrated 1/2'' Shower Thermostatic...

1 Answer

Installation problem: Grohmix shower valve 1 1/2'' extension


This is what you should have... Grohe Grohmix Thermostat Valve & Trim - 34436
  • Paraffin cartridge
  • Lever volume control
  • Grip ring temperature control
  • 1/2" NPT female connections
  • Service stops
  • Includes rough-in valve and trim
  • Integrated temperature and volume control
  • Requires Twin Ell (03 671) for shower/tub combinations with diverter spout Note:
  • Requires Twin Ell (03 671) for shower/tub combinations with diverter spout
  • Grohe Grohmix Thermostat Valve & Trim - 34436

    Mar 26, 2009 | Grohe Grohmix Thermostat Valve & Trim -...

    1 Answer

    Grohe Thermostatic Valve


    the temp, control valve is getting to hot!!! there for only let so much hot water go thru, did you take the inner parts out when soldering this in, if not you might have damaged it, and if so need to replace the cartdrige

    Feb 10, 2009 | Grohe Integrated 1/2'' Shower Thermostatic...

    Not finding what you are looking for?
    Plumbing Logo

    Related Topics:

    234 people viewed this question

    Ask a Question

    Usually answered in minutes!

    Top Grohe Plumbing Experts

    Donni Steen

    Level 3 Expert

    659 Answers

    john h

    Level 3 Expert

    12173 Answers

    Mike

    Level 3 Expert

    4340 Answers

    Are you a Grohe Plumbing Expert? Answer questions, earn points and help others

    Answer questions

    Manuals & User Guides

    Loading...