The product is a mixing fitting for the bathtub with electronic control of water temperature and filling volume. If an electronic drain / overflow fitting is installed, filling and emptying of the bathtub can be regulated using the mixing fitting.

On technical requirements met and the use in potable water installations, see Regulations from section: Application areas .

A drain/overflow, water inlet and a pipe interrupter are required for the complete mounting of the product. Further information on this can be found at Accessories .

Regular maintenance is part of running the system properly Maintenance .

The electronic mixing fitting is intended to fill a bathtub with the individually desired water temperature. For this purpose, the mixing fitting has three memory locations in which the individual preferred settings for water temperature, fill volume, and fill depth of the tub can be saved and used for the next bath.

The electronic mixing fitting has been optimised for controlling electrically operated Viega bathtub drains/overflows. When a manually operated drain and overflow fitting is used, all functions of the mixing fitting can be used, except for the electronic opening and closing of the drain.

The following basic functions at the mixing fitting can be controlled electronically:

• Starting and stopping the water inlet

• Setting the water temperature

• Setting the strength of the water inlet

• Switching between bathtub inlet and hand shower

• Opening and closing the bathtub drain (only with electronically controlled processes; see product portfolio)

• Saving, using, and deleting personal settings

Special functions are those functions not required for the daily use of the mixing fitting. Special functions are for example basic settings and maintenance and cleaning functions.

The mixing fitting has the following special functions:

• Diagnosis mode for performing a functionality test

• Performing a thermal disinfection

• Resetting the factory settings

• Enabling the safeguarding function for locking "Thermal disinfection" and "Reset to factory settings"

• Unlocking the temperature safeguard

• Cleaning mode for short-​term disabling of the control element, e.g. for cleaning

• Automatic opening and closing of the drain set if the respective Viega drain set has been mounted (motor-​driven drain plug)

The mixing fitting is equipped with a rechargeable battery that supplies power to the mixing fitting in the event of a power failure in order to close the mixing fitting.

The rechargeable battery is immediately recharged after the power supply is restored.

The mixing fitting has two functions protecting the user from scalding:

• From a temperature of 40 °C, the temperature setting via the control element is stepped down with factor 1:10. This means that the temperature is increased at a much slower rate so that the user cannot unintentionally set a much higher temperature.

  The temperature reduction takes place at the normal rate even if the scalding protection is enabled.

• Thermal disinfection can be disabled via the option lock. This function can for example be used to protect children from scalding.

The electronic mixing fitting differentiates between two operating statuses:

• Operating status "OFF" with water supply switched off

• Operating status "ON" with water supply switched on

The available functions depend on the current operating status.

The control element can be pressed and turned.

Keep pressed long = Illuminated ring indicates different menu functions.

Press briefly = Water flows in / water inlet stops

Turn = Make various settings (e.g. change water temperature).

Pressing and holding the control element calls up the menu. As long as you keep control element A pressed, the different menu functions are displayed one after the other. The menu functions are distinguished by different colours on the illuminated ring. Each colour signifies a different menu function (see table below).

All instructions for operating the mixing fitting are of a uniform structure. Two factors influence the function of the product, and a combination of these factors brings a result. These two factors are the current operating status and the action carried out by the user.

Example:

The following requirements exist for the mounting of the mixing unit:

• The mixing unit may only be mounted horizontally or vertically as shown in the illustration.

• The mixing unit must remain accessible for the purpose of maintenance and the top of the casing must be removable.

  Mounting can take place in e.g. a side room or in a pre-​wall inspection opening.

• A 230 V connection is available as power supply, see Regulations from section: Mounting the mixing unit .

• The mixing unit must not be so far away from the control element that the connection cable (3 m) is subjected to tensile stress.

  If required, the connection cable of the control element can be extended to 6 m Accessories .

The following requirements exist for the mounting of a control element:

• The element should be easily reachable from both inside and outside the tub.

• Fixing can take place on an even surface with the dimensions 60 x 60 mm (e.g. in the pre-​wall) or on the tub rim.

• A drill hole with a diameter of 38–40 mm is required for fixing an element.

• If mounting is to take place on the tub rim, Viega recommends having the drill holes made by the manufacturer, if possible.

• There must be clearance of at least 40 mm provided behind or below the mounting area.

• The connection cable must be laid free of tensile stress from the installation position of an element to the controller unit.

  If required, the connection cable can be extended from 3 m to 6 m Accessories .

• When mounting on the tub rim, it must be ensured that the elements are never submerged in water. Contact with splash water does not present a problem.

The following requirements exist for the mounting of the drain / overflow:

• The bathtub is installed.

• The drain pipeline is installed all the way to the bathtub.

• The underside of the bathtub is accessible.

To ensure that no bath water flows back into the potable water installation, a pipe interrupter must be installed in the pipeline between the mixing unit and the bathtub inlet.

The following schematic diagram shows what this should look like:

It is important that the pipe interrupter is mounted vertically, in the direction of flow and at least 150 mm above the upper edge of the bathtub.

Observe the local standards and regulations.

The pipe interrupter is not included in the scope of delivery and must be ordered separately. Observe the instructions for use of the pipe interrupter.

Requirements:

• The installation location is permanently accessible even after mounting, and the casing cover can be removed (e.g. through an inspection opening).

• The installation location is situated in such a way that the installation location of the control elements can be reached with a cable of 3 m length (6 m with extension).

• A 230 V connection is available as power supply, see Regulations from section: Mounting the mixing unit .

• The mixing unit can be mounted with the connections facing either down or to the left. Other mounting positions or mounting at an angle impair the functionality of the mixing unit.

Mounting of the control element is shown here at the bathtub rim by way of example. For mounting it at another surface, e.g. in the pre-​wall, the same steps and preconditions apply.

Requirements:

• The planned installation location of the control element can be reached from the installation location of the mixing unit with a cable of 3 m length (6 m with extension).

• At the installation location, there is a drill hole with a diameter of 38–40 mm.

• Behind the drill hole, there is a clearance of at least 40 mm.

An electrically driven drain and overflow fitting must be used to be able to open and close the drain using the control element. Viega recommends one of the four models mentioned in Accessories . The motor of these models has a connection through which it is connected to the control of the mixer unit.

Requirements:

• The mixer unit has been mounted.

• The motor-​powered drain and overflow fitting has been mounted.

• The mixer unit is accessible and the lid had been removed.

• The motor of the drain and overflow fitting can be accessed from the installation location of the mixing unit using a 3 m cable (5 m with extension).

The electronic mixing fitting has three program memory locations to which the users can save their individual settings. The individual settings include the water temperature, the strength of the water stream and the water volume defined via the inflow time.

The program memory locations are assigned the following values in the factory setting:

• Program memory location 1: 12 °C, 100 % water stream strength, 45 min inflow time

• Program memory location 2: 25 °C, 100 % water stream strength, 45 min inflow time

• Program memory location 3: 38 °C, 100 % water stream strength, 45 min inflow time

You can also control the water supply and temperature via the program memory, see Filling the bathtub using the program memory .

The mixing unit has three program memory locations through which the water supply can take place:

• Briefly press the control element 1 x = program memory location 1

• Briefly press the control element 2 x = program memory location 2

• Briefly press the control element 3 x = program memory location 3

The program memory locations save personal settings for bathtub filling (temperature, water flow volume and water stream strength). When a program memory location is called up, the bathtub fills automatically with the preset values.

Use this function to reset all settings to delivery state (see Factory settings ).

While the function lock is enabled, the functions "Thermal disinfection" and "Reset to factory settings" are blocked. The function lock servers as a child protection or safeguard against unauthorised use.

In care mode, the electronic mixing unit is disabled for 45 seconds. This allows you to clean the control element, for example, without accidently triggering a function.

You can disable the care mode before expiry of the 45 seconds by pressing the control element once more until the illuminated ring goes out.

Thermal disinfection is a five-​minute program, and ensures that germs in the mixing unit are removed by hot water. The mixing unit is flushed through at the maximum supply temperature. The least amount of water is used.

The fitting can carry out an automatic system diagnosis. The sensors for temperature and volumetric flow are tested.

During the analysis, the illuminated ring of the control element shows which component of the product is being checked right now.

Display during analysis:

• Illuminated ring inactive: automatic adjustment of the valves

• Illuminated ring red: hot water valve opens fully (caution: risk of scalding!)

• Illuminated ring green: hot water valve closes fully

• Illuminated ring blue: cold water valve opens fully

• Illuminated ring inactive: cold water valve closes fully

After completion of all analysis steps, the illuminated ring of the control element indicates the findings.

The following findings can be displayed:

• Illuminated ring flashes amber twice: device functions properly

• Illuminated ring flashes amber three times: temperature sensor defective – check the connection and replace

• Illuminated ring flashes amber four times: flow sensor defective – check the connection and replace

Normal soap or a mild cleaning agent can be used for regular maintenance and prevention of lime scale on the control elements. Use no scouring agent or abrasive objects.

Strong stains can be removed using typical household cleaner. Rinse the detergent very thoroughly with clear water after the prescribed dwell time. There should be no residue on the components.

If the rechargeable battery is not sufficiently charged (e.g. due to age), the mixing unit will close and can no longer be used. The control element then flashes red five times.

Viega recommends replacing the battery every 3–5 years, depending on use.

For a description of the replacement of the battery, see Replacing the rechargeable battery .

Depending on the local water quality, the filters in the corner valves must be cleaned or replaced regularly. At commissioning, specify a maintenance interval which is in keeping with the local water quality.

For a description of the filter replacement, see Changing the filters in the corner valves .

Some of the causes for malfunctions can be identified by system diagnosis. Since the system diagnosis tests important (also safety-​relevant) functions of the fitting, carry out a system diagnosis regularly.

Viega recommends running a system diagnosis every 18 months. When the device is used very often, reduce the interval correspondingly.

To prevent germ infestation of the water even with infrequent use of the bathtub, Viega recommends carrying out a thermal disinfection in the following cases and intervals:

• after the bathtub has not been used for 72 hours, see Regulations from section: Maintenance

• otherwise after 7 days at the latest, see Regulations from section: Maintenance

Depending on the local water quality, the filters in the corner valves need to be changed regularly.

Requirements:

• The corner valves are accessible (e.g. through a revision opening).

Requirements:

• The mixing unit is accessible (e.g. through a revision opening).

• The lid of the mixing unit can be removed.

• A spare battery is available.