Mira Excel Operation manual

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These instructions are to be left with the user
Installation & User Guide
MIRA EXCEL
SHOWER CONTROL

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CONTENTS
Introduction ............................................................................................. 3
Important Safety Information ................................................................. 4
Pack Contents Checklist ......................................................................... 5
Dimensions ............................................................................................. 7
Specifications .......................................................................................... 8
1. Pressure Ranges ............................................................................. 8
2. Temperature Control ........................................................................ 8
3. Standards and Approvals ................................................................. 8
4. Flow Rates ....................................................................................... 9
Installation Requirements .................................................................... 10
Typical Suitable Installations ............................................................. 10
Installation ............................................................................................. 14
Excel ...................................................................................................... 14
1. Back inlet supplies (rising or falling concealed pipework) ............... 14
2. Exposed supplies (rising or falling surface pipework) .................... 17
Excel B .................................................................................................. 22
3. Solid and dry-lined walls................................................................. 22
4. Stud Partitions and Shower Enclosures (Front Face) ..................... 28
5. Laminated Panels and Shower Enclosures (Rear Face) ................. 29
Control Assembly Fitting Instructions ................................................. 31
Reversed Inlet Connections .................................................................. 32
Commissioning ..................................................................................... 34
1. Maximum temperature setting ........................................................ 34
2. Maximum Temperature Settings for Reversed Inlet Connections .. 36
3. Temperature override button - disable ............................................ 37
Operation ............................................................................................... 38
Fault Diagnosis ..................................................................................... 39
Maintenance .......................................................................................... 43
1. Cleaning ......................................................................................... 43
2. Cartridge assembly - renewal ......................................................... 43
3. Cartridge assembly 'O' seals/inlet strainers - renewal ..................... 43
Spare Parts ............................................................................................ 44
Customer Service .................................................................... Back Page

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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 Excel is a thermostatic shower control with independent selection of spray
force and temperature. The shower control incorporates a wax capsule temperature
sensing unit. This provides an almost immediate response to changes in pressures
or temperature of the incoming water supplies to maintain the selected temperature.
An adjustable maximum temperature stop is provided which limits the temperature to
the desired level. An override button allows the user to exceed the preset maximum
temperature. The flow control utilizes ceramic plate technology operating directly on
the hot and cold inlets to provide precise control and isolation of the incoming water
supplies. Inlet filters are fitted to protect the thermostatic control mechanism.
The Mira Excel (Exposed Version) has adjustable inlets to fit pipework centres between
150 mm and 155 mm.
Shower controls covered by this guide:
Mira Excel
An exposed shower control for connection to wall mounted or rear entry pipework.
Mira Excel B
A built-in shower control for connection to concealed pipework.
INTRODUCTION
If you experience any difficulty with the installation or operation of your new shower
control, then please refer to "Fault Diagnosis", before contacting Kohler Mira Limited.
Our telephone and fax numbers can be found on the back cover of this guide.

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IMPORTANT SAFETY INFORMATION
Warning!
1. Products manufactured by us are safe and without risk provided they are installed,
used and maintained in good working order in accordance with our instructions
and recommendations.
Caution!
1. Read all of these instructions.
2. Retain this guide for later use.
3. Pass on this guide in the event of change of ownership of the installation site.
4. Follow all warnings, cautions and instructions contained in this guide.
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 the young, the elderly, the infirm, or anyone inexperienced in the correct
operation of the controls.
6. When this product 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.

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9
PACK CONTENTS CHECKLIST


Tick the appropriate boxes to familiarize yourself with the part names and to
confirm that the parts are included.
Excel shower control
Documentation
1 x Installation and User Guide 
1 x Customer Support Brochure 
1 x Installation Template 
1 x Excel 
1 x O-Key 
2 x Compression Nuts 
2 x Olives 
2 x Pipe Concealing Plates 2 x Wall Plugs 
2 x No. 8 x 3/4" Screws 

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Excel B shower control
Documentation
1 x Installation and User Guide 
1 x Customer Support Brochure 
1 x Installation Template 
1 x Concealing
Plate Assembly 
1 x Excel B 
(with building-in shroud)
1 x Shroud 
1 x Knob Assembly 
2 x No.8 x 1 1/4" Screws 
4 x M5 x 50 mm Screws (2 fitted) 
2 x M4 x 30 mm Screws 
2 x Wall Plugs 
3 x Compression Nuts 
3 x olives 

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DIMENSIONS
Excel
NOTE:- NOT TO SCALE - All dimensions are nominal and in millimetres
Excel B
134 208
150 - 155
100
38
22
61 - 78
151
155
155
208

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SPECIFICATIONS
1. Pressure Ranges
Excel & Excel B
1.1. Minimum maintained pressure: 0.1 bar (1.0 metre head) when used with Mira
shower fittings.
1.2. Maximum maintained pressure: 5.0 bar.
1.3. Maximum static pressure: 10 bar.
Note! Nominally equal inlet supply pressures are recommended for optimum
performance.
2. Temperature Control
2.1. Close temperature control is provided between 35 °C and 45 °C.
Note! The temperature control specification, outlined below, is achieved with the
blend set between 35 °C and 45 °C, with supply temperatures of 15 °C cold and
65 °C hot, AND, nominally equal inlet supply pressures.
2.2. The blended temperature is maintained within 2 °C with a 10 °C change in the hot
or cold supply.
2.3. The wax capsule sensor effects a shut down to seepage in approximately
2 seconds if the cold supply fails. Shut down to seepage is only achieved if the
hot supply is 12 °C above the blend temperature.
3. Standards and Approvals
3.1. Designed to comply with BS EN 1111 and 1287 for thermostatic mixing valves,
and to be used within systems designed to BS6700.
3.2. BS 6700 recommends that the temperature of stored water should never exceed
65 °C. A stored water temperature of 60 °C is considered sufficient to meet all
normal requirements and will minimise the deposition of scale in hard water areas.

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4. Flow Rates
Note! Pressure conversion: 1 bar = 10 m head of water = 100 kPa
'%156#46
56#46
5116*'
(14%'
EXCEL WITH LOGIC FITTINGS LOW CAPACITY SPRAY PLATE
'%156#46
56#46
5116*'
(14%'
EXCEL WITH LOGIC FITTINGS HIGH CAPACITY SPRAY PLATE
0
012345
Pressure Loss (Bar)
Flow Rate (L/Min)
10
20
30
40
50
0
012345
Flow Rate (L/Min)
10
20
30
40
50
Pressure Loss (Bar)

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INSTALLATION REQUIREMENTS
Typical Suitable Installations
Key to symbols appearing throughout this guide.
Read the section 'Important Safety Information' first.
Installation must be carried out in accordance with these instructions, and must be
conducted by designated, qualified and competent personnel.
1. Installations must comply with UK Water Regulations/ Bye-laws (Scotland), and
Building and Plumbing Regulations in force at the time of installation.
2. Layout and sizing of pipework must be such that when other services are used,
pressures at the shower control inlets are maintained approximately equal and
do not fall below the recommended minimum.
3. Do not install the product in a position in which service access is restricted.
4. Do not fit any form of flow control in the shower outlet, only Mira recommended
fittings should be used.
5. Do not use excessive force when making connections.
6. Do not install the product in a position where it could become frozen.
7. Supply pipes must be flushed to clear debris before connecting the shower control.
8. Conveniently situated isolating valves must be fitted for servicing purposes.
9. If the shower control is to be used with a fully modulating multipoint water heater,
fully modulating combination boiler, thermal store or unvented system an
expansion vessel must be fitted to accommodate the expansion of water in the
domestic hot water supply (this may already be part of the system, check the
details on the boiler/heater or contact the boiler/heater manufacturer).
Float operated valve
Stop or servicing valve
Shower control
Warning or overflow pipe
Drop tight pressure reducing valve
(PRV)
Twin impeller inlet pump
Tempering valve
Mini expansion vessel
Non-return valve

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HOT
COLD
Instantaneous gas-heated showers (e.g. combination boilers)
The shower control MUST be installed with a multipoint gas water heater or combination
boiler of a fully modulating design (i.e. where the water draw-off rate indirectly
controls the gas flow rate to the burner).
A drop tight pressure reducing valve MUST be fitted if the supply pressures exceed 5
bar maintained.
An expansion vessel MUST be fitted (and regularly maintained) as shown in the
diagram below to ensure that excess pressures do not damage the product. This may
already be fitted within the boiler (check with the manufacturer) and is in addition to
the normally larger central heating expansion vessel.
The hot supply temperature MUST be at least 12 °C hotter than the required blend
temperature for optimum performance.
Gravity fed showers
The shower control MUST be fed from a cold water storage cistern and hot water
cylinder providing nominally equal pressures.

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Combined outlet PRV
with internal non-return valves
- Expansion vessel required.
Cold takeoff after PRV
- Expansion pressure taken up by
unvented cylinder expansion vessel.
Unvented mains pressure showers
The shower can be installed with an unvented, stored hot water cylinder. Only a
"competent person" as defined by Part G of Schedule 1 of the Building Regulations
may fit this type of system.
For packages with no cold water take off after the appliance reducing valve, it will be
necessary to fit an additional drop tight pressure reducing valve when the mains
pressure is over 5 bar. The drop tight pressure reducing valve must be set at the
same value as the unvented package pressure reducing valve.
Note! An expansion vessel MUST be fitted (and regularly maintained) if any form of
backflow prevention device is fitted, e.g. non-return valve, PRV. This will ensure that
excess expansion or pulse pressures do not damage the product or the plumbing
system.
Reduced pressure to cold inlet of shower
Reduced pressure
to unvented cylinder
High Inlet Pressure
Expansion Vessel
Reduced pressure to
unvented cylinder
Reduced pressure to
cold inlet of shower
High Inlet Pressure
HOT
COLD
Safety devices not shown for
clarity

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Mains pressurised instantaneous hot water shower, heated from a thermal
store
Packages of this type, fitted with a tempering valve can be used.
A drop tight pressure reducing valve MUST be fitted if the supply pressures exceed
5 bar maintained.
An expansion vessel MUST be fitted (and regularly maintained) if any form of backflow
prevention device is fitted, e.g. non-return valve, PRV. This will ensure that excess
expansion or pulse pressures do not damage the product or the plumbing system.
The expansion vessel may already be fitted externally or internally within the thermal
store (check with thermal store manufacturer).
Pumped showers (inlet pumps)
The shower can be installed with an inlet pump (twin impeller). The pump MUST be
located on the floor next to the hot water cylinder. The hot water cylinder/vent pipes
must be arranged as shown to achieve air separation.
90°
30 to 60°
Air Separation
COLD HOT

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INSTALLATION
Excel
1. Back inlet supplies (rising or falling concealed pipework)
Read the section: Installation Requirements first.
1.1 Decide on a suitable position for the
shower control. The position of the
shower control 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 back-siphonage.
1.2 Use the installation template to mark
the positions of the holes for the
backplate and the pipe centres.
1.3 For solid walls drill the backplate holes
with a 6 mm diameter drill and insert
the wall plugs (supplied). For other
types of wall structure alternative fixing
may be required.
1.4 Use the two No. 8 x 1 3/4" fixing
screws (supplied) to fix the backplate
to the wall. Make sure that the two
angled fixing holes are at the bottom
of the backplate.
Spirit Level
Hose Retaining Ring
25 mm Minimum
Spill-over Level
Installation Template
Fixing Screw
Backplate
Wall Plug

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1.5 Use a spirit level and pencil to mark
the route of the hot and cold water
supply pipes at 150-155mm centres.
Note! The Excel is supplied with inlet
connections hot left, cold right and
bottom outlet as standard. For
installations with reversed hot and cold
supplies complete the installation and
refer to section: Reversed Inlet
Connections.
1.6 Remove the plaster and brick/block to
the required depth to conceal the
pipework.
Note! Depth must be sufficient to
prevent pipe concealing plates fouling
on the plumbing elbows.
1.7 Install the supply pipes. The pipes
must project 18 mm from the finished
surface of the wall at 150-155mm
centres.
Note! Use the installation template to
ensure pipes are in the right position.
1.8 Finish the surface of the wall as
required. The recesses from which
the pipes emerge must also
accommodate the 32 mm diameter x
10 mm deep flanges on the pipe
concealing plates.
1.9 Fit the pipe concealing plates over the
hot and cold supply pipes.
Concealing Plates
18 mm from
finished wall
surface
150-155 mm
Centres
32 mm
Dia

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1.10 Thoroughly flush the hot and cold
water supply pipes. The supplies
must be clean and free from debris
before connecting the shower
control. Failure to do so may result
in product malfunction.
1.11 Slide the compression nuts and olives
over the supply pipes.
1.12 Locate the Excel shower control on to
the backplate and supply pipes and
hold it in position.
Note! Align the adjustable inlets to aid
location onto the pipework.
1.13 Use a suitable screwdriver to tighten
the two screws in the backplate. The
screws will hold the shower control in
position.
1.14 Use a suitable spanner to
tighten the compression nuts
(anticlockwise rotation when viewed
from front). Protect the chromium
plated surfaces with a cloth.
Do not overtighten.
1.15 Turn on the water supplies and check
for any leaks.
Shower fittings
1.16 Install the shower fittings. Refer to the
Installation and User Guide for the
shower fittings.
Olive
Compression
Nut
Backplate
Screws

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2. Exposed supplies (rising or falling surface pipework)
Read the section: Installation Requirements first.
Rising Supplies
2.1 Decide on a suitable position for the
shower control. The position of the
shower control 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 back-siphonage.
2.2 Use the installation template to mark
the positions of the holes for the
backplate and the pipe centres.
2.3 For solid walls drill the backplate holes
with a 6 mm diameter drill and insert
the wall plugs (supplied). For other
types of wall structure alternative fixing
may be required.
2.4 Fix the backplate to the wall with the
two fixing screws (supplied). Make
sure that the angled fixing holes are at
the bottom of the backplate.
Hose Retaining Ring
25 mm Minimum
Spill-over Level
Installation Template
Fixing Screw
Backplate
Wall Plug

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2.5 Use the O-Key or a suitable
screwdriver to remove the blanking
plugs from the rising supply inlets.
2.6 Use the O-Key to remove the inlet
nipple bolts from the rear supply inlets.
2.7 Remove the inlet nipples.
2.8 Align and fit the inlet nipples, complete
with 'O' seals, into the rising supply
inlets.
2.9 Fit and tighten the inlet nipple bolts with
the O-Key.
Note! The nipple will still float when
the bolt has been tightened.
2.10 Screw the blanking plugs, complete
with washers into the rear supply inlet
nipple holes. Tighten the blanking plugs
using the O-Key or suitable
screwdriver.
2.11 Locate the Excel shower control on to
the backplate.
2.12 Use a suitable screwdriver to tighten
the two screws in the backplate. The
screws will hold the shower control in
position. Do not overtighten the
screws.
Blanking Plugs
Inlet Nipple
Bolts
O-Key
Inlet Nipples
Washer
Blanking Plugs
Inlet Nipples
O-Key
Inlet Nipple
Bolts
'O' Seal
Washers

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2.13 Install the hot and cold supply pipes
38 mm from the finished wall at
150-155 mm centres.
Use the installation template to make
sure the pipes are in the right position.
Note! The Excel is supplied with inlet
connections hot left, cold right and
bottom outlet as standard. For
installations with reversed hot and cold
supplies complete the installation and
refer to section: Reversed Inlet
Connections.
Note! Thoroughly flush the hot and
cold water supply pipes. The supplies
must be clean and free from debris
before connecting the shower control.
Failure to do so may result in product
malfunction.
2.14 Slide the compression nuts and olives
over the supply pipes.
2.15 Insert the hot and cold supply pipes
fully into the inlet nipples and slide the
olives and compression nuts into
place.
Note! Align the adjustable inlets to aid
location onto the pipework.
2.16 Use a suitable spanner to tighten the
compression nuts. Protect the
chromium plated surfaces with a cloth.
2.17 Turn on the water supplies and check
for any leaks.
Olive
Compression Nut
Installation
Template

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Falling Supplies
2.18 Follow the installation instructions 2.1
to 2.10 inclusive.
2.19 Use the O-Key to remove the outlet
nipple.
2.20 Carefully lever the outlet cap from the
outlet blanking plug in the shower
control body.
2.21 Use the O-Key to remove the outlet
blanking plug.
2.22 Screw the outlet nipple, complete with
'O' seal into the hole previously
blanked. Tighten the outlet nipple with
the O-Key.
2.23 Screw the outlet blanking plug,
complete with 'O' seal, into the outlet
hole between the two inlet nipples.
Tighten the outlet blanking plug with
the O-Key.
2.24 Fit the outlet cap correctly. The
matching contours of the outlet cap
and shower control body must be
aligned.
2.25 Locate the Excel shower control on to
the backplate.
Tapered End
Outlet Cap
Outlet Blanking
Plug
Outlet Nipple