ELECTRIC SHOWER Installation & User Guide THESE INSTRUCTIONS ARE TO BE LEFT WITH THE USER 1
Contents Introduction .......................................................................................................... 3 Important Safety Information ............................................................................. 4 Pack Contents Checklist ...................................................................................... 7 Specifications ...................................................................................................... 8 Dimensions ............................
Introduction Thank you for purchasing a quality Mira Zest Shower. To enjoy the full potential of your new shower, please take time to read this guide thoroughly, and keep it handy for future reference. Mira Zest electric showers have separate controls for power selection and for temperature/flow adjustment. A unique flow regulator stabilises any temperature changes caused by water pressure fluctuations, which can result from taps being turned on or off or toilets being flushed.
Important Safety Information WARNING! 1. Products manufactured by us are safe and risk-free, provided that they are installed, used and maintained in good working order, in accordance with our instructions and recommendations. 2. THIS APPLIANCE MUST BE EARTHED. 3. In accordance with ‘The Plugs and Sockets etc. (Safety) Regulations’ in force at the time of installation, this appliance is intended to be permanently connected to the fixed electrical wiring of the mains system. 4.
CAUTION! 1. Read all of these instructions and retain this guide for later use. 2. Pass on this guide in the event of change of ownership of the installation site. 3. Follow all warnings, cautions and instructions contained in this guide, and on or inside the appliance. 4.
9. When this appliance has reached the end of its serviceable life, it should be disposed of in a safe manner, in accordance with current local authority recycling, or waste disposal policy.
Pack Contents Checklist Tick the appropriate boxes to familiarise yourself with the part names and to confirm that the parts are included.
Specifications Dimensions 103mm 310mm 205mm 53mm 8
Wiring Diagram 9
Plumbing 1. Minimum maintained inlet pressure for satisfactory operation: 0.7 bar 2. Maximum static inlet pressure: 10 bar 3. Minimum static pressure to keep the flow valve closed: 0.5 bar Electrical 1. The appliance requires a 40 Amp fuse. 2. The terminal block will not accept cable larger than 10 mm2. Standards and Approvals 1. This Mira Zest shower complies with all the relevant directives for CE marking. Flow Rate Graph Temperature Rise (°C) 1.
Installation Requirements Plumbing 1. The Mira Zest 7.5 kW and 8.5 kW electric showers are designed to operate with a minimum maintained inlet pressure of 0.7 bar up to a maximum static inlet pressure of 10 bar. 2. The appliance is normally connected to the cold water mains-fed supply.
9. Do not install the appliance in a position where it may become frozen. The shower unit must not be fitted where it may be exposed to freezing conditions. The shower unit must not be used if you suspect it may be frozen. 10. We recommend that a non-restrictive (free-flowing) isolating valve is fitted in the cold water supply pipe to allow the complete maintenance of the appliance. Do not use a valve with a loose washer plate (jumper) as this can lead to a build up of static pressure. 11.
15. A hose retaining ring is supplied to prevent the handset from dropping below the spillover level of the bath or shower, which could lead to contamination from back-siphonage. Hose Retaining Ring 25 mm minimum Spillover Level The supplied hose retaining ring should meet the majority of user requirements for shower installations with flexible outlet fittings. However, there will be occasions when the hose retaining ring will not provide a suitable solution.
Electrical 1. In a domestic installation, the rating of the electricity supply company fuse and the consumer unit must be adequate for the additional demand. This is a highpower appliance, and it is essential to contact your electricity supply company to ensure that the supply is adequate for the appliance. Voltage drop due to local heavy demand will reduce the performance of the shower. 2. The appliance must be earthed by connecting the supply-cable earth conductor to the earth terminal. 3.
6. A separate, permanently connected supply must be taken from the consumer unit to the appliance through a double-pole switch, which has a minimum 3 mm contact separation. The switch can be a ceiling mounted pull-cord type within the shower room, or a wall mounted switch in an adjacent room. 7. DO NOT twist the individual cable cores of the live and neutral conductors, as this will prevent them from entering the terminal block. 8. DO NOT exert strain on the terminal block. 9.
Installation WARNING! Isolate the electrical and water supplies before installing the shower. 1. Decide on a suitable position for the appliance (minimum distance of 200mm from the ceiling to allow for cover fit and removal). The position of the appliance and the shower fittings must provide a minimum gap of 25 mm between the spill-over level of the shower tray/bath and the handset. This is to prevent backsiphonage 2.
8. 9. Determine the direction of the incoming water supply: falling (entering the shower from the top), or rising (entering the shower from the bottom). Do not use an incoming supply entering the shower directly from the back. Add an elbow to the supply pipe and connect it as a rising or falling supply. Rotate the inlet connector to suit the direction of the incoming water supply. 10. The case has thinned sections that can be removed to allow entry of the supply pipe and electrical cables.
12. Secure the shower to the wall loosely through the top two fixing holes, using the supplied screws. 13. Mark the position of the bottom fixing hole. 14. Remove the shower from the wall. Drill the bottom fixing hole and insert the supplied wall plug. 15. Thoroughly flush the mains-fed cold water supply pipe. The supply must be clean and free from debris BEFORE connecting the appliance. 16. Replace the shower on the wall and secure through the three fixing holes, using the supplied screws. 17.
18. Bring the electrical cables into the case. 19. Strip back sufficient of the outer cable insulation to enable routing to terminal block. 20. Fit an earth sleeve to the earth wire. 21. Loosen the screws in the terminal block and insert the bare wires into the clamps. L (Live) = Brown wire T (Earth) = Green sleeved wire N (Neutral) = Blue wire Note! Do not twist the cores of the wires or strain the cables to make them reach the terminal block. 22. Connect the conductors firmly into the terminal block.
23. If necessary, fit an earth bonding clamp to the supply pipe and ensure that the bonding complies with the relevant regulations in force at the time of installation. 24. Replace the service tunnel. 25. Replace the cover. If the cover does not fit easily, rotate the knobs slightly so that they fit onto the spindles. Do not force the cover. 26. Tighten the three cover screws.
Commissioning Commissioning If you are unsure how electric showers work, please read through the Operation section before continuing. 1. Make sure that the TOP control knob is in the 'STOP' position and that the electrical supply has been isolated. 2. Turn the BOTTOM control knob fully anticlockwise to the full cold position. 3. Turn the water supply fully on at the isolating valve, check that water is not leaking from the bottom of the case. 4.
Operation Advice to Users 1. Electric showers work by taking in cold water and passing it over the heating elements contained in the tank inside the shower. 2. The showering temperature is adjusted by turning the temperature control knob, which varies the flow of cold water across the elements. The slower the rate of flow, the warmer the water, and vice versa. The holes in the spray plate of the shower handset should always be kept clean to maintain a consistent flow and stable shower temperatures.
Operation Instructions Note! Read the Important Safety Information section first. WARNING! The spray plate holes must be kept clear. The spray plate should be regularly removed and cleaned in descalent. Lack of regular spray plate cleaning will lead to poor performance and cause early failure of the appliance. See the shower fittings User Guide for more information. To turn the shower on 1. Switch on the electrical supply at the double pole switch. 2. Turn the power knob to High.
To turn the shower off 1. Turn the power knob to Stop. Note! A small amount of water may continue to flow from the handset for a few moments. 2. Switch off the electrical supply at the double pole switch.
Fault Diagnosis Customer Fault Diagnosis The troubleshooting information below gives details on what you can do as a user if you encounter problems with the shower. If this information does not fix the problem, contact the installer for advice. Read the Important Safety Information section first and refer to the appliance diagram. WARNING! There are no user-serviceable components beneath the cover of the appliance. Only a competent tradesperson should remove the cover.
Malfunction No water or very low flow rate. No hot water from shower, with the knobs in any position. Shower temperature cycles between hot and cold. Cause Remedy The handset sprayplate is blocked. Clean the handset sprayplate. Refer to the Maintenance section of the handset manual. The incoming water supply stop valves, or the appliance isolating valve, is closed. Open the stop/isolating valve completely. The hose or handset is blocked. Clear the blockage or replace the hose or handset.
Installer Fault Diagnosis The troubleshooting information below gives details on solutions to problems with the shower, for installers. Before replacing any parts, ensure that the underlying cause of the malfunction has been resolved. Read the Important Safety Information section first and refer to the appliance diagram. Malfunction No hot water from shower, with the knobs in any position. Shower temperature cycles between hot and cold. Turning the temperature knob does not affect the water temperature.
Malfunction Cause Remedy No water or very low The handset sprayplate is Regularly clean the handset flow rate. blocked. sprayplate. Refer to the Maintenance section of the handset manual. Open the stop/isolating valve The incoming water supply stop valves, or the completely. appliance isolating valve, is closed. The hose or handset is blocked. Clear the blockage or replace the hose or handset. Insufficient water supply pressure. Contact the local water authority.
Malfunction Water leaks from the bottom of the case near the outlet, and there is no flow from the handset. The water can not be turned off. Cause Remedy The pressure relief valve in the tank has been triggered, (the shower has a pressure relief valve assembly that works to reduce the damage if the outlet is blocked or the unit is frozen). Resolve the blocked outlet, and replace the tank assembly.
Maintenance Any maintenance must be carried out by a qualified tradesperson, following the instructions provided. Before replacing any parts, ensure that the underlying cause of the malfunction has been resolved. WARNING! There are no user-serviceable components beneath the cover of the appliance. Only a competent tradesperson should remove the cover. Cleaning Many household and industrial cleaners contain abrasives and chemical substances that can damage the finish of your shower.
3. Use a suitable spanner to remove the filter from the inlet connector assembly. Hold a wrench across the flats of the inlet connector assembly to prevent damage to the connector, whilst removing the strainer. Inlet Filter Inlet Connector Assembly 4. Remove the inlet filter. 5. Clean the inlet filter with a stiff brush. If necessary, use a kettle descalent in accordance with the manufacturer's instructions. Refit the components in reverse order. 6.
Relief Valve Assembly - Resetting WARNING! Isolate the electrical and water supplies before removing the cover. Mains electricity connections are exposed when the cover is removed. 1. Remove the three screws that hold the cover, remove the cover. Note! The rubber ball is ejected to reduce the damage if the outlet is blocked or the appliance is frozen. 2. Remove the five screws that hold the switch assembly, heater tank and, flow regulator assembly.
Flow Regulator Assembly/Switch Assembly- Removal and Installation WARNING! Isolate the electrical and water supplies before removing the cover. Mains electricity connections are exposed when the cover is removed. 1. Remove the three cover retaining screws, the cover and the service tunnel. 2. Remove the hose from the outlet connector and loosen the connection to the inlet connector. 3. Remove the six screws that hold the switch assembly, heater tank, flow regulator assembly and inlet connector.
5. Carefully pull off the two brown wires attached to the microswitch. Note the position of the wires. Microswitch 6. Carefully pull off the blue wire and brown wire from the solenoid, fitted to the flow regulator. Note the position of the wires.
7. Carefully pull the flow regulator assembly, switch assembly and the heater tank away from the case. Carefully separate the flow regulator from the switch assembly and inlet connector by gently pulling apart. Switch Assembly Heater Tank Inlet Connector Flow Regulator Assembly 8. Refit the components in reverse order. Make sure that the electrical wires and ‘O’ seals are installed in the correct positions.
Heater Tank - Removal and Installation WARNING! Isolate the electrical and water supplies before removing the cover. Mains electricity connections are exposed when the cover is removed. 1. Remove the three cover retaining screws, the cover and the service tunnel. 2. Remove the hose from the outlet connector and ease the inlet connector off the inlet supply pipe. 3. Remove the six screws that hold the inlet clamp bracket, flow regulator assembly, switch assembly, and heater tank.
4. Remove all wiring from the switch assembly. Switch Assembly Note! Using long nose pliers, gently squeeze the lever lock on the top two spade connection, and pull them off the switch assembly. Carefully pull the two lower connections off the switch assembly. 5. Lever Lock Spade Connection Carefully pull off the blue wire to the solenoid, fitted to the flow regulator. Note the position of the wire. Solenoid 6. Ease off both thin brown wires attached to the microswitch.
7. Lift out the flow regulator assembly, switch assembly and the heater tank from the case. 8. Carefully separate the flow regulator assembly from the switch assembly, inlet connector and heater tank by gently pulling apart. 9. Make a note of the positions of all the wiring on top of the heater tank. Switch Assembly Heater Tank Inlet Connector Flow Regulator Assembly 10. Remove the screw that holds the green earth wire to the thermal trip. Thermal Trip Green Earth Wire 11.
Thermal Trip - Removal and Installation WARNING! Isolate the electrical and water supplies before removing the cover. Mains electricity connections are exposed when the cover is removed. 1. Remove the three cover retaining screws, and the cover. 2. Make a note of the positions of the wiring on top of the heater tank. 3. 4. Remove the screw that holds the green earth wire to the thermal trip. Ease the thermal trip away from the heater tank. Thermal Trip Brown Red Brown Green Earth Wire 5.
Spare Parts Spare Parts List 406.27 439.75 439.76 439.77 439.79 439.81 439.87 439.88 439.89 439.90 439.91 439.92 439.95 439.99 Filter Inlet Connector Assembly Clamp Bracket Pack (components identified ‘A’) Flow Reg Assembly 7.5/8.5 kW Switch Assembly, Rotary Cover Assembly, Zest Terminal Block Assembly Seal Pack (components identified ‘B’) Screw Pack (components identified ‘C’) Thermal Trip Assembly Heater Tank Assembly 7.5 kW Heater Tank Assembly 8.
Spare Parts Diagram 439.79 B A 439.75 406.27 C B 439.77 C 439.90 A 439.87 C B B C 439.95 439.99 439.91 439.92 439.
Notes 42
Notes 43
Customer Service Mira Showers guarantee products against any defect of Spare Parts materials or workmanship for one year from the date of We maintain an extensive stock of spares, and aim to have purchase. functional parts available for ten years from the date of final To validate the guarantee, please return your completed manufacture of the product. registration card.