Mira Orbis User manual

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These instructions are to be left with the user
Installation and User Guide
Mira Orbis Thermostatic Electric Shower

2
Contents
Introduction .............................................................................................3
Guarantee.................................................................................................4
Patents and Design Registration ...........................................................4
Important Safety Information .................................................................5
Warning! ............................................................................................... 5
Caution! ................................................................................................ 6
Pack Contents Checklist ........................................................................8
Specifications ..........................................................................................9
Installation Requirements ...................................................................... 9
Installation .............................................................................................12
Installation of Mira Orbis.....................................................................12
Commissioning .....................................................................................16
User Instructions...................................................................................18
Clock Setting ...................................................................................... 23
Fault Diagnosis......................................................................................25
Heater Settings...................................................................................25
Maintenance...........................................................................................29
Handset - Cleaning.............................................................................29
Inlet Filter - Cleaning/Renewing .........................................................29
Clock Battery Replacement Procedure ..............................................30
Dimensions ............................................................................................31
Wiring Diagram......................................................................................32
Spare Parts ............................................................................................ 33
Accessories ...........................................................................................35
Notes ......................................................................................................36
Customer Services................................................................................39

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Introduction
Thank you for purchasing a quality Mira product. To enjoy the full potential of your
new product, please take time to read this guide thoroughly. Having done so, keep
it handy for future reference.
The Mira Orbis is a thermostatic electric shower with separate controls for power
selection and temperature/flow adjustment. A unique thermostatic valve stabilises
temperature changes caused by water pressure fluctuations. These can result from
taps being turned on or off, or toilets being flushed. A digital display indicates shower
temperature, clock (with battery backup), low flow and over temperature warnings.
The Mira Orbis comes complete with a set of Mira Energise Shower Fittings.
Mira Orbis 9.0 kW
A 9.0 kW 240 V AC (8.2 kW 230 V AC) heater with Mira Energise adjustable spray
handset with four different spray actions (start, soothe, force and eco*). Supplied
complete with flexible hose, clamp bracket assembly, slide bar, supports, hose
retaining ring and soap dish. Available in white/chrome.
Mira Orbis 9.8 kW
A 9.8 kW 240 V AC (9.0 kW 230 V AC) heater with Mira Energise adjustable spray
handset with four different spray actions (start, soothe, force and eco*). Supplied
complete with flexible hose, clamp bracket assembly, slide bar, supports, hose
retaining ring and soap dish. Available in white/chrome and black/chrome finish.
Mira Orbis 10.8 kW
A 10.8 kW 240 V AC (9.9 kW 230 V AC) heater with Mira Energise adjustable spray
handset with four different spray actions (start, soothe, force and eco*). Supplied
complete with flexible hose, clamp bracket assembly, slide bar, supports, hose
retaining ring and soap dish. Available in white/chrome finish.
* The eco setting reduces the water flow to give economical use of water, whilst
still giving an adequate shower performance. This setting performs best with most
gravity, pumped, and mains pressure unvented systems. On electric showers and
some combination boiler systems the economy setting will have no effect, and will
give the same spray action as the start setting.
If you experience any difficulty with the installation or operation
of your new Electric Shower, please refer to ‘Fault Diagnosis’,
before contacting Kohler Mira Ltd.
Our telephone and fax numbers can be found on the back cover of this guide.

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Patents and Design Registration
Design Registration 000738141-0002
Patents GB: 2 341 667, 2 404 000, 2 428 286
Eire: 82835
Patent Applications UK: 2 427 460
Eire: 2004/0483, 2006/0462, 2008/0289
Recommended Usage
Domestic 
Light Commercial 
Heavy Commercial 
Healthcare 
Guarantee
For domestic installations, Mira Showers guarantee the Mira Orbis against any
defect in materials or workmanship for a period of two years from the date of purchase
(shower fittings for one year).
For non-domestic installations, Mira Showers guarantee the Mira Orbis against
any defect in materials or workmanship for a period of one year from the date of
purchase.
For terms and conditions refer to section “Customer Services”.

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Important Safety Information
Installation must be carried out in accordance with these instructions, and must be
conducted by designated, qualified and competent personnel.
WARNING!
Follow all warnings, cautions and instructions contained in this guide, and on or
inside the shower.
1. This shower can deliver scalding temperatures if not operated, installed
or maintained in accordance with the instructions, warnings and cautions
contained in this guide and on or inside the appliance.
1.1. 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.
1.2. This product is suitable for installation within Zone 1 and is rated IP X4.
1.3. Isolate the electrical and water supplies before commencing installation. The
electricity must be turned off at the mains and the appropriate circuit fuse
removed, if applicable.
1.4. Mains connections are exposed when the cover is removed.
1.5. Refer to the wiring diagram before making any electrical connections.
1.6. Make sure all electrical connections are tight, to prevent overheating.
1.7. Make sure that any pipework that could become frozen is properly insulated. The
shower unit must not be fitted where it may be exposed to freezing conditions.
The water supplies to this product must be isolated if the product is not to be
used for a long period of time. If the product or pipework is at risk of freezing
during this period they should also be drained of water.
1.8. DO NOT switch on if there is a possibility that the water in the shower is
frozen.
1.9. DO NOT install the product in a position in which service access is restricted.
1.10.DO NOT commission this appliance if water leaks from the unit or the heater tank
pressure relief valve. If water leaks from the pressure relief valve, maintenance
will be required before the shower can be safely used.
1.11.DO NOT fit any form of outlet flow control as the outlet acts as a vent for the
tank body. Only Mira recommended outlet fittings should be used.
1.12.This product is not suitable for areas with high humidity (i.e steam rooms).
Please consult your installer.
1.13.THIS APPLIANCE MUST BE EARTHED. MAKE SURE SUPPLEMENTARY
BONDING COMPLIES WITH THE ‘REQUIREMENTS FOR ELECTRICAL
INSTALLATIONS’.
In accordance with the current edition of ‘The Plugs and Sockets etc. (Safety)
Regulations in force at the time of installation, this shower is intended to be
permanently connected to the fixed electrical wiring of the mains system.

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1.14.This appliance must be provided with means for disconnection that is
incorporated into the fixed wiring in accordance with the relevant local wiring
regulations.
Caution!
2.1. Read all of these instructions and retain this guide for later use.
2.2. The electrical installation must comply to 'BS 7671 - Requirements for Electrical
Installations', commonly referred to as the IEE Wiring Regulations - Part 7, or
any particular regulations and practices, specified by the local electricity supply
company.
2.3. The plumbing installation must comply with the requirements of UK Water
Regulations/Bye-laws (Scotland), Building Regulations or any particular
regulations and practices, specified by the local water company or water
undertakers.
2.4. Make sure that you fully understand how to operate this shower and make sure
that it is properly maintained in accordance with the instructions given in this
manual.
2.5. Anyone who may have difficulty understanding or operating the controls of any
shower should be attended whilst showering. Particular consideration should
be given to:
2.5.1. The young.
2.5.2. The elderly.
2.5.3. The infirm.
2.5.4. The disabled.
2.5.5. Anyone who suffers from a medical condition that can result in temporary
incapacity (e.g. epilepsy or blackouts).
2.5.6. Anyone inexperienced in the correct operation of the controls.
2.6. This appliance is not intended for use by persons (including children) with
reduced physical, sensory or mental capabilities, or lack of experience and
knowledge, unless they have been given supervision or instruction concerning
the use of the appliance by a person responsible for their safety.
2.7. Children should be supervised to make sure that they do not play with the
appliance.
2.8. Sunburn or skin conditions can increase your sensitivity to hot water. Make
sure that you set the shower to a cooler temperature.

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2.9. If any of the following conditions occur, isolate the electricity and water supplies
and refer to 'To contact us', on the back page of this guide.
2.9.1. If the cover is not correctly fitted and water has entered the appliance
case.
2.9.2. If the case is damaged.
2.9.3. If the appliance begins to make an odd noise, smell or smoke.
2.9.4. If the appliance shows signs of a distinct change in performance,
indicating a need for maintenance.
2.9.5 If the shower is frozen.
2.9.6 DO NOT operate this appliance if water leaks from this appliance.
3. Switch off the appliance at electrical isolating switch when not in use. This is
for safety and is recommended with all electrical appliances.
4. DO NOT position the handset to spray water directly on to the appliance.
e.g. when cleaning shower control.
5. 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.
6. Make sure that this guide is left with the user.

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Pack Contents Checklist
Mira Orbis
3 x Wall Plugs
3 x Fixing Screws
1 x Mira Orbis
1 x Compression Nut
1 x Olive
2 x Case Inserts
Tick the appropriate boxes to familiarise yourself with the part names and to
confirm that the parts are included.
Documentation
1 x Guarantee Registration Document
1 x Installation Template
1 x Installer Checklist

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Specifications
1. Plumbing
Minimum maintained inlet pressure for 9.0 kW and 9.8 kW, 70 kPa (0.7 bar)•
for satisfactory operation.
Minimum maintained inlet pressure for 10.8 kW, 100 kPa (1.0 bar) for
•
satisfactory operation.
Maximum static inlet pressure 1000 kPa (10 bar).
•
Minimum static pressure 20 kPa (0.2 bar) to keep the inlet valve closed.•
2. Electrical
The Mira Orbis 9.0 kW requires a 40 Amp circuit protection device.
•
The Mira Orbis 9.8 kW requires a 45 Amp circuit protection device.•
The Mira Orbis 10.8 kW requires a 45 Amp circuit protection device.•
The terminal block will accept cable up to 16 mm².•
3. Standards and Approvals
The Mira Orbis complies with all relevant directives for CE marking.•
Installation Requirements
1. Plumbing
The appliance is designed to operate with a minimum maintained inlet pressure•
of 0.7 bar (for 9.0 kW and 9.8 kW) and 1.0 bar (for 10.8 kW) up to a maximum
static inlet pressure of 10 bar.
When installed in very hard water areas (above 200 ppm temporary hardness)
•
your installer may advise the installation of a water treatment device, to reduce
the effects of limescale formation. Your local water company will be able to
advise the hardness of water in your area.
It is recommended 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 pressures.
The appliance is suitable for installation within the shower area. It is fitted with
•
a pressure relief device and must be positioned over a water catchment area
with the controls at a convenient height for all users.
The appliance must be fitted on to a finished flat and even wall surface (this
•
wall surface should be tiled or waterproofed). DO NOT fit the appliance to
the wall and tile up to the case. For safety requirements, an air gap must be
left behind the appliance.

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Avoid layouts where the shower hose will be sharply kinked. This may reduce•
the life of the hose.
A Soap Dish/Hose Retaining Ring is supplied to prevent the handset from
•
dropping below the spill-over level of the bath or shower tray, which could
lead to contamination from back-siphoning. 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 it will not provide
a suitable solution. In these instances an outlet double checkvalve, e.g. a
Mira DCV-H, must be fitted. This will increase the required supply pressure
typically by 0.1 bar (see section “Accessories”).
Supply pipework
• MUST be flushed to clear debris before connecting to the
appliance.
To avoid damage to the case when soldered fittings are used, pre-solder the
•
pipework and fittings before connecting them to the inlet connector assembly.
Refrain from applying excessive force when making any connections. Always
provide mechanical support when making the plumbing connections.
The appliance is fitted with a brass inlet compression assembly for connecting
•
to a 15 mm supply pipe from the top, bottom or back. The fitting of double
checkvalves in the inlet supply to the appliance, can cause a pressure
build-up, which could exceed the maximum static inlet pressure and damage
the appliance.
Isolating Valve
Avoid Sharp Kinks
Convenient height
for all the family
25 mm Min.
Bath
Shower Tray
Fixed to finished
wall surface
Minimum
200 mm from
ceiling
Hose Retaining Ring

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2. Electrical
In a domestic installation, the rating of the electricity supplier’s fuse and the•
consumer unit must be adequate for the additional demand. All Mira electric
showers are high power units, it is essential to contact your electricity supplier
to ensure that the supply is adequate for the product. Voltage drop due to
local heavy demand will reduce the shower’s performance.
The appliance
• must be earthed by connecting the supply-cable earth
conductor to the earth terminal. Supplementary bonding: Within the bathroom
or shower room, all accessible conductive parts of electrical equipment and
extraneous conductive parts (metal parts) that are likely to introduce earth
potential, must be electrically bonded to earth using a minimum cable size of
4.0 mm2 if the cable is not mechanically protected, (2.5 mm2if mechanically
protected).
The minimum cable size (cross-sectional area) required should be in
•
accordance with BS 7671.
As a guide only, and in accordance with BS 7671 we recommend close circuit
•
protection: i.e. 9.8 kW = 45 Amp
A 30mA Residual Current Device (RCD)
• MUST be included in the electrical
circuit. This may be part of the consumer unit or a separate unit.
A separate, permanently connected supply must be taken from the consumer•
unit to the appliance through a double-pole switch, which has at least 3 mm
contact separation. The switch can be a ceiling mounted pullcord type within
the shower room or a wall mounted switch in an adjacent room.
DO NOT
• twist the individual cable cores of either the live or neutral conductors,
as this will prevent them from entering the terminal block.
DO NOT
• exert strain on the terminal block. Make sure that the electrical
connections are tightly screwed down.
DO NOT• turn-on the electrical supply until the plumbing has been
completed.

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Double-pole
Isolating Switch
Consumer Unit
Installation
Installation of Mira Orbis
Warning! Turn off the electrical and water supplies before proceeding with the
installation of the Mira Orbis. The electricity must be turned off at the mains and
the appropriate circuit fuse removed, if applicable.
Note! An installation template is supplied to help you install the Mira Orbis.
Remove the three cover retaining
screws.
Carefully remove the cover, making
sure that you do not strain the multi-
connector.
Carefully remove the multi-connector
from the socket on the control PCB in
the case
Remove the service tunnel.
Cover
Cover Retaining
Screw
Service Tunnel

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Two case inserts are supplied with the Mira Orbis, so that they can be trimmed
to suit the supplies entering the product. Before fitting the cover, make sure that
the case inserts are fitted.
Thoroughly flush the mains-fed cold water supply pipe. The supply must
be clean and free from debris BEFORE connecting the Mira Orbis.
To flush the pipework, turn on the water supply and drain a minimum of 10 litres
(2 gallons) of water into a bucket or catchment area. Turn off the water supply.
An installation template is supplied to help you install the Mira Orbis.
Put the installation template on the wall and mark through the positions of the
fixing holes. Make sure that the position of these holes do not come in line with
any buried cables or pipework. Make sure that sufficient electrical supply cable
is available for connection to the terminal block.
Drill and plug the top two fixing holes. Secure the Mira Orbis to the wall with the
screws provided. Drill the bottom fixing hole with the product in place. Alternative
fixings (not supplied) may be necessary for some wall structures. Avoid drilling
into any supply cable/pipe.
Determine the direction of the inlet
water supply: top (falling), bottom
(rising), or back inlet.
Note! Make sure that the back inlet
does not go directly back into the wall.
Use a soldered elbow.
Swivel the inlet connector assembly
to suit. Remove the inlet blanking cap.
Avoid trapping the green earth bonding
wire.
Install the mains-fed cold water supply
pipe. Do not overtighten.

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Feed cable into Case. Fit Earth sleeve
(not supplied) and strip insulation.
Do not twist cable cores.
Firmly connect the conductors. Do not
exert strain on the terminal block.
L = BROWN
E = GREEN/YELLOW
N = BLUE
Before refitting the cover, pull the plastic
tab off the battery to activate it.
Refit the Service Tunnel.
Connect the multi-connector to the
socket on the PCB.
Refit the Cover. Make sure that it fits
correctly. Do not overtighten screws.
Do not use alternative screws to secure
the Cover. This can cause internal
damage to the appliance. Do not seal
around the back of appliance.
Install the shower fittings in accordance
with the manufacturer’s instructions.
Cover
Cover Retaining
Screw
Service Tunnel
Important! Make sure
that the inlet earth wire is
routed as shown. Failure
to do so may cause
product malfunction.

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Cold Water Supply
Pipe (Bottom Entry)
Service Tunnel
Fixing Screw
Holes For Cover
Retaining Screws
Case Insert
Electrical
Supply Cable
Terminal
Block
Inlet Connector
Assembly
Heater Tank

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Commissioning
If you are unsure how an electric shower works, please read through the User
Instructions section before continuing.
Note! The temperature display throughout this guide will depend upon inlet supply
conditions and product settings.
Turn control to full cold. Turn the water supply
fully on.
Check for water leaks. Switch on the electrical
supply and press the
‘Start/Stop’ button
The temperature indicator
becomes illuminated,
showing time. Temperature
will be displayed after a few
seconds.
Press the ‘Low’ button,
light on the button comes
on
Water will be at full force
and at a cool temperature
as indicated by the
temperature indicator.
Turn the control slowly.
Temperature remains cool
and flow is reduced
Electrical supply is turned
off at the mains.
0 - 5 Secs
1.
4.
3.2.
6.5.
9.8.7.
5 - 10 Secs

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Turn control to full cold. The temperature will rise
slightly as indicated by the
temperature indicator.
0 - 10 Secs
12.11.10.
The flow rate will increase.
Adjust temperature as
required. Flow rate will adjust
automatically.
5 - 10 Secs
13.
15.
14.
16.
Press STOP button, light on the
temperature indicator dims to standby
state. When the shower has stopped
running the temperature display will
only show the clock. The water flow
will continue for a few seconds before
stopping. Isolate power. Display will go
blank.
Press the ‘Medium’ button,
light on the button comes
on
Press the ‘High’ button,
light on the button comes
on

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The warmer the
shower, the lower
the flow rate and vice
versa.
Heated water is produced by adjusting the flow of cold water passed through a
heater tank.
The shower has three
heater settings.
User Instructions
How Your Electric Shower Works
The shower will purge water from
its tank for a few seconds.
Residual water may drain over a
few minutes.
17. 18.
Note! A slight hissing sound may be heard from the Mira Orbis during operation.
High mains water pressure and high shower temperatures will affect the tone. This
is quite normal in use.
0 - 5 Secs
The temperature
indicator shows the
temperature of the
shower.

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The shower's top priority is to keep the desired water temperature constant. Electric
showers with thermostatic control are able to keep a stable temperature across the
range from hot to cold, whilst also dealing with fluctuations in electrical and water
supplies. As a result, there is a temperature limit the shower cannot go beyond. For
safety, this temperature is factory set and cannot be adjusted to make the shower
hotter or colder.
Thermostatic (Temperature-Stable)
THERMOSTATIC
ELECTRIC
SHOWER
ORDINARY
ELECTRIC
SHOWER

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Water inlet pressure fluctuations due to other draw offs (e.g. flushing toilet). Shower
temperature will be controlled to within ± 2°C of the set temperature provided that
the supply conditions remain within the required operating parameters (refer to
section: ‘Specifications’).
For a cold shower select ‘Low’.
For a summer warm shower select ‘Medium’.
For a winter warm shower select ‘High’.
During extremes of mains water supply temperature, adjust heater setting to obtain
a better showering temperature.
The Effect of Seasonal Changes
The Effect of Other Water Devices
Example of how shower temperature
stabilises due to pressure changes.