1. Introduction
This manual provides essential information for the safe and efficient installation, operation, and maintenance of your GROHE 29120000 Thermostatic Mixer. Please read these instructions carefully before beginning installation or use, and retain them for future reference.
Product Features:
- GROHE QuickFix installation system for simplified setup.
- Control of water outlets via intuitive SmartControl push-buttons.
- GROHE SmartControl: intuitive operation by pressing a button.
- Scratch-resistant surface with GROHE StarLight coating for lasting brilliance.

Image Description: This image displays the GROHE 29120000 thermostatic mixer. It features a circular chrome faceplate with two push-button controls for water outlets and a larger rotary knob for temperature adjustment, marked with a 38-degree Celsius safety stop. An integrated shower holder is visible on the right side.
2. Safety Information
Always observe local plumbing and building codes. Installation should be performed by a qualified professional to ensure proper function and safety. Before installation, ensure the main water supply is turned off. Avoid using abrasive cleaners or solvents on the chrome finish, as this may damage the GROHE StarLight coating.
3. Package Contents
Verify that all components are present before beginning installation:
- GROHE 29120000 Thermostatic Mixer unit
- Mounting hardware
- Instruction manual
4. Installation
The GROHE 29120000 Thermostatic Mixer is designed for concealed installation. The GROHE QuickFix system facilitates a straightforward and secure mounting process. Professional installation is highly recommended.
Important Note: Rapido Smartbox Requirement
This thermostatic mixer requires the separate GROHE Rapido Smartbox 35600000 for installation. The Smartbox serves as the universal rough-in unit for various GROHE SmartControl trim sets.

Image Description: This image highlights a crucial installation requirement: the GROHE 29120000 thermostatic mixer needs the GROHE Rapido Smartbox 35600000 for proper installation. The image shows the mixer's internal components and the necessary Smartbox, emphasizing their compatibility.
System Overview
The SmartControl system allows for flexible configuration of your shower. The diagram below illustrates how the universal box integrates with various shower components.

Image Description: This diagram illustrates the modular nature of the GROHE SmartControl system. It shows the central SmartControl universal box (item 4) and various compatible components such as different shower heads (item 2), hand showers (item 3), and different styles of control panels (item 1). The arrows indicate water flow and connections for a complete shower system.
- Ensure the Rapido Smartbox 35600000 is securely installed within the wall according to its specific instructions.
- Connect the water supply lines to the Smartbox.
- Mount the GROHE 29120000 trim set onto the Smartbox, ensuring all connections are tight and sealed.
- Test for leaks before finalizing the wall finish.
5. Operation
The GROHE 29120000 Thermostatic Mixer provides precise control over water flow and temperature for an optimal showering experience.
Water Flow Control (SmartControl Buttons)
The two push-buttons on the mixer control the water flow to different outlets (e.g., overhead shower, hand shower). Press a button to turn on the water flow to the corresponding outlet. Rotate the button to adjust the water volume from a gentle spray to a powerful jet. Press the button again to turn off the water flow.
Temperature Control
The large rotary knob at the bottom of the mixer controls the water temperature. Rotate the knob to adjust the temperature. The 38°C mark indicates a safety stop to prevent accidental scalding. To increase the temperature beyond 38°C, press the safety override button (usually integrated into the knob) and continue rotating.
6. Maintenance
Regular cleaning and care will ensure the longevity and appearance of your GROHE thermostatic mixer.
Cleaning the Finish
The GROHE StarLight chrome finish is scratch-resistant and easy to clean. Use only a soft cloth and mild soap or a specialized GROHE cleaning product. Avoid abrasive sponges, scouring agents, or cleaners containing alcohol, acids, or solvents, as these can damage the surface.
Filter Maintenance
Periodically check and clean the integrated filters (if accessible) to prevent reduced water flow caused by debris or sediment.
7. Troubleshooting
If you experience issues with your thermostatic mixer, consult the following common solutions:
- No water flow or low pressure: Check if the main water supply is open. Ensure filters are clean and not obstructed.
- Temperature fluctuations: Verify that the hot and cold water supplies are correctly connected. Clean the thermostatic cartridge if necessary (professional assistance recommended).
- Leaking: Check all connections for tightness. If the leak persists, contact a qualified plumber.
For persistent problems, contact GROHE customer support or a certified service technician.
8. Specifications
| Attribute | Detail |
|---|---|
| Manufacturer | Grohe |
| Item Model Number | 29120000 |
| Product Dimensions (LxWxH) | 18 x 34.5 x 14.7 cm |
| Item Weight | 1.94 Kilograms |
| Color | Chrome |
| Finish | Chrome |
| Material | Metal |
| Style | 2 shut-off valves with shower holder |
| Shape | Round |
| Installation Method | Widespread (Concealed) |
| Number of Holes | 2 |
| Handle/Lever Placement | Central |
| Handle/Lever Material | Metal |
| Usage | Shower |
| Included Components | Thermostatic unit |
| Inlet Connection Type | BSPT |
| Outlet Connection Type | BSPT |
| Number of Ports | 2 |

Image Description: This technical drawing provides the precise dimensions of the GROHE 29120000 thermostatic mixer. It shows a width of approximately 24.31 cm, a height of 20 cm, and a depth of 18 cm from the wall, including the integrated shower holder. These measurements are essential for planning installation.
9. Warranty and Support
GROHE products are manufactured to the highest quality standards and come with a manufacturer's warranty. For specific warranty terms and conditions, please refer to the documentation provided with your purchase or visit the official GROHE website. For technical support, spare parts, or service inquiries, please contact GROHE customer service.





