We continue with our focus on Digital Showers by taking you through some of our most asked questions from fellow installers when it comes to installing and configuring our wireless Mira Digital Showers.
Typical Installation Scenarios
As you know all Mira Digital Showers are essentially available in two options; a High Pressure/ Combi Boiler Valve and a Pumped Valve for Gravity Fed Systems. We recommend the correct digital valve for the following typical installations.
- For a household with an Instantaneous Multipoint Water Heaters and Combination Boiler then you need to recommend a Mira digital shower- high pressure/combi valve, for example, the Mira Platinum Dual Ceiling Fed - high pressure/combi
- For a household with a mains pressurised instantaneous hot water shower, heated from a thermal store, again we would recommend the high pressure/combi valve option, for example, the Mira Platinum Dual Rear Fed - High Pressure / Combi boiler Shower
- Households with gravity fed systems where the shower control must be fed from a cold water storage cistern and a hot water cylinder we recommend our Pumped for Gravity Systems digital valve, for example, Mira Platinum Dual Rear Fed Pumped for Gravity
The adjacent schematic shows a good installation set-up of wireless digital showers such as the Mira Platinum or Mira Vision.
- A separate, permanently connected supply must be taken from the ring main to the appliance through a 3 amp double pole switched fused spur providing a minimum 3mm contact separation gap in each pole.
- Ensure the switched fused spur is easily accessible for servicing and resetting purposes.
- The use of supply-line or zone strainers will reduce the need to remove debris at the Digital Mixer Valve. The recommended maximum mesh aperture dimension for such strainers is 0.5 mm.
- Pipework must be rigidly supported to avoid any strain on the connections.
- A 30m Residual Current Device (RCD) must be included in the electrical circuit. This may be part of the consumer unit or a separate unit.
- Long inlet pipework (dead-legs) should be kept to a minimum to avoid temperature fluctuations.
- Supply pipework layout must be arranged to minimize the effect of other outlet usages upon the dynamic pressures at the Digital Mixer Valve inlets.
- To eliminate pipe debris it is essential that supply pipes are thoroughly flushed through before connection to the Digital Mixer Valve.
Valve Installation Orientation
The Digital Mixer Valve (which contains the thermostatic mixing valve) may only be orientated in the positions shown above when mounted on a vertical or horizontal surface. Failure to do so will compromise the ability of the unit to fail-safe and deliver constant blend. If the power supply cable is damaged, it must be replaced by the manufacturer or a service engineer.
While is good to cover best practice, it’s important to ensure poor installation can be avoided. Here are some of the most common practices that we would advise against.
We recommend the following:
- Installation Conditions - we recommend you avoid Installing the Digital Mixer Valve where it can become frozen and where it can be subjected to ambient temperatures in excess of 40ºC
- Easy access to the digital mixer valve for any maintenance is key. Please avoid positioning the digital mixer valve where maintenance access is poor or unsafe.
- Do not install the digital shower into a system where the cold water cistern holds less than 230 litres and into a system where air locking could occur.
To avoid poor communication between the mixer valve and wireless controller, do not install the mixer valve under a metal bath, in front of the metal cistern, on foil backed plasterboard, more than the recommended distance away etc.