Mira Enhance Operation manual

1
Installation & User Guide
SHOWER PUMP
THESE INSTRUCTIONS ARE TO BE LEFT WITH THE USER

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ii
Contents
Section
1 ..... Important Safety Information ........................................... 3
2 ..... Introduction
Description ................................................................. 5
Operation ................................................................... 5
3 ..... Specifications:
Weight ........................................................................ 7
Dimensions ................................................................ 7
Power Supplies .......................................................... 7
Water Standards ........................................................ 8
Connections ............................................................... 8
4 ..... Pack Contents Checklist:
Mira Enhance Shower Pump ..................................... 9
Documentation ........................................................... 9
5 ..... Installation:
Plumbing .................................................................. 10
Electrical .................................................................. 14
6 ..... Commissioning
Commissioning ................................................................. 17
7 ..... Maintenance:
Fault Diagnosis ........................................................ 18
Appendices:
1 ..... Parts List:
Spare Parts .............................................................. 20
Guarantee, Customer Care Policy, and How to contact us
Back cover
Page

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Section
1Important Safety Information
1.WARNING!
1.1. Products manufactured by Mira are precision engineered and should give
continuous superior and safe performance provided they are installed, operated
and maintained in accordance with the instructions and recommendations
given in this manual.
1.2. Installation must be carried out by qualified personnel only.
Failure to comply with these safety instructions will cause risk to people and
equipment and may invalidate the guarantee.
Identified hazards are highlighted by the following symbols:
Danger from general causes:
Danger from electrical causes:
Instructions which if ignored could cause damage or impair the function of
the pump are highlighted by the word: ATTENTION
2. Caution!
2.1. Read all of these instructions and retain this manual for later use.
2.2. Pass on this manual in the event of change of ownership of the installation site.
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. The installation should be carried out by a plumber or contractor
who is registered, or is a member of, an association such as:
2.3.1. Institute of Plumbing (IOP), throughout the UK.
2.3.2. National Association of Plumbing, Heating and Mechanical Services
Contractors (NAPH & MSC), England and Wales.
2.3.3. Scottish and Northern Ireland Plumbing Employers’ Federation
(SNIPEF), Scotland and Northern Ireland.

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WARNING - THIS APPLIANCE MUST BE EARTHED.
2.4. WARNING! THIS APPLIANCE MUST BE EARTHED. MAKE SURE
SUPPLEMENTARY BONDING COMPLIES WITH THE "REQUIREMENTS
FORELECTRICALINSTALLATIONS",oranyparticularregulationsorpractices,
specified by the local electricity supply company.
The pump is supplied with a pre-wired flow switch and mains cable and must
be permanently connected to the fixed wiring of the mains system.
Warning! Do not use a plug and socket.
2.5. The inclusion of a Residual Current Device (RCD) (Earth trip) with a trip current
of 30mA is recommended. This may already be part of the consumer unit.
2.7. 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.
Standards and Approvals
1. The Mira Enhance complies with all the relevant directives for CE marking.

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2
Section Introduction
1. Description
The Mira Enhance single impeller centrifugal pump is designed to receive a single
gravity feed from a mixing valve and provide a pressurized supply to a fixed shower
head or shower handset. (Refer to Figures 2 and 3). The pump is not suitable for an
installation in the system layouts shown in Figures 4 and 5.
The pump is more effective when pushing water along a pipe rather than pulling. Thus
the pump is best positioned as close to the hot water or blend water source as possible
to reduce cavitation (air bubbles) in the pipes. The greater the static (inlet) water
pressure on the pump the better it will operate. Thus positioning a pump at high level
is not advantageous, and may result in inferior performance.
Due consideration should be made to the pump position as any noise generated may
be amplified by installation conditions such as reverberant panels etc. The pump motor
is air cooled and it is important that the flow of air around the motor is not impeded. The
pump should be sited in a frost free area and inlet/outlet pipework layouts which can
create significant airlocks are best avoided.
ATTENTION: Pipework on the outlet side of the pump that could be prone to airlocks
can be fitted with a float-type automatic air vent (bottle vent) at the highest point as
shown in Figure 3. This will ensure that air released in the hot water during the pumping
and heating process can be vented.
The stored hot and cold water volumes should be sufficient for the required duty.
Typical minimum flow rates are 10 l/min for a pulsating handset or overhead shower.
The manufacturer’s data for the outlet fittings should be consulted.
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 safe
for future reference.
2. Operation
The pump would normally start automatically when the mixing valve is set to open. The
contacts of the flow switch at the pump outlet close when the flow rate in the outlet pipe
is more than 1.4 l/min. When this occurs the electrical circuit to the motor is completed
and the pump operates. The opposite action occurs when the mixing valve is set to
shut.
A vertical distance of 300 mm between the water discharge point through the shower
outlet and the base of the cistern would typically achieve the flow rate required.
However, long pipe runs or restrictive terminal fittings will increase the gravity head
required to produce the required flow.

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To overcome an initial low flow rate in the outlet pipe it is possible to bypass the function
of the flow switch by the addition of a momentary action switch connected in parallel
with the flow switch (Refer to Figure 6). When the mixing valve is set to on and the
momentary action switch operated, the pump will run. The pump will then maintain the
necessary flow rate in the outlet pipe and will continue to operate until the mixing valve
is set to off.
Suitable momentary action switches are as follows:
}ceiling mounted pull cord switch
MK4408P wall mounted seal switch
Crabtree CT2147
MK3190RCWH1(5A)

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1.Weight
Mira Enhance Shower Pump = 2.7 kg (Pump only)
2. Dimensions
14
140
100
53
160
51
107
12 (offset)
All dimensions are nominal and in millimetres
External Dimensions
Figure 1
3.Power Supplies
3.1. Single Phase 230V 50Hz fused supply through a 5A fused connection unit
or equivalent, refer to Figure 6.
3.2. Absorbed Power Approximately 85W during normal working conditions.
3
Section Specifications

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4.Water Standards
4.1. This product complies with all relevant directives for CE marking.
4.2. Maximum Hot Water Temperature 80oC. It is recommended that stored
water temperatures should never exceed 65oC. The use of hot water above
60oC may lead to cavitation (air bubbles) which will increase pump noise and
reduce the service life of the product. A temperature of 60oC is considered
sufficient to meet all normal requirements and will minimize the deposition
of scale in hard water areas.
4.3. Delivery Rates See Pump Performance Graph. Terminal fittings and
associated pipe work will reduce this figure.
0.6
0.5
0.4
0.3
0.2
0.1
0
0 5 10 15 20 25
Mira Enhance Shower Pump Performance Graph
Flow Rate (l/min)
Total Head Pressure (bar) at Pump
4.4. ATTENTION: Inlet Pressure Maximum inlet static pressure 3 bar (30m
head).
5. Connections
5.1. Plumbing
Inlet - compression fitting to fit 22mm copper pipe
Outlet - compression fitting to fit 15mm copper pipe.
FS4 Flow switch - push-fit fitting to fit 15mm copper pipe.

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Section Pack Contents Checklist
1. Mira Enhance Shower Pump


 Tick the appropriate boxes to familiarize yourself with the part names and to
confirm that the parts are included.

Mira Enhance Shower Pump 
Inlet Adaptor 
Flow Switch 
Resilient Pad 
2. Documentation
1 x Installation, Operation and Maintenance Guide 
1 x Customer Support Brochure 

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5
Section Installation
5
1. Plumbing
WARNING
ATTENTION: DO NOT FIT INLET CHECK VALVES. INLET CHECK VALVES CAN
SERIOUSLY DAMAGE THE PUMP.
1.1. ATTENTION: The pump must be mounted in a horizontal position with the
outlet connection vertically upwards. The operation of the flow switch will be
impaired in any other position.
1.2. Operational difficulties may be experienced if plumbing layouts shown in
Figures 4 and 5 are used.
1.3. ATTENTION: The pump and pipes must not be installed against wood,
plastic or any other material which may be effected by heat from the pump.
1.4. The hot feed from the cylinder must be as illustrated. Side entry cylinder bosses
are not recommended. A drop in cylinder water level could expose a top entry
immersion element. Air in water gathers at the edge of the cylinder, and in the
centre, during the heating process, before travelling up the vent.
1.5. ATTENTION: Water pumps can develop leaks and should, therefore, not be
situated where seepage may go undetected or cause damage. The pump must
be installed such that it is accessible for servicing or removal. When servicing
or disconnecting, small amounts of water may drain from the unit and pipework.
1.6. Pump performance is maximised by the use of 22 mm pipe, especially on the
inlet pipework and where long outlet pipe runs are used.
1.7. Pipe jointing should be via P.T.F.E. tape or fluid sealant. Do not use hemp and
paste which may affect the operation of the flow switch and plastic internal
components.
1.8. ATTENTION: Care should be taken when using soldering fluxes. Protect the
pump from damage whilst making soldered connections as some fluxes cause
damage to plastic components.
1.9. Pipe connections to the pump should be supported to reduce strain and
must be correctly aligned prior to installing the pump to reduce the risk of
scolding.

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1.11. Ensure no fluid drips onto the pump motor or its electrical connections
during installation, venting or operation as when the pump is energised this
may create a risk of electric shock.
1.12. Joint and assemble the adapter to the pump inlet. Do not overtighten the
adapter.
1.13. Install a short length of 15mm pipe at the pump outlet, tighten the
compression joint. Push the flow switch onto this pipe (end marked Inlet first)
ensuring that the flow switch is fitted vertically (See to Figure 7).
1.14. Place the pump on its resilient pad and complete the inlet and outlet pipe
work.
1.10. It is recommended that inlet/outlet isolation valves are fitted within close
proximity of the pump to permit isolation for servicing (See Figures 2 & 3).

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B
Minimum
1.5m with
simultaneous
other hot
water
services
Cistern
Warning Pipe
(overflow)
Cold feed
to cylinder
Cold feed to
mixing valve
25 mm
A
30o to 60o
90o
DHW Pump
Other hot
water services
B
A
Key to symbols used in the system layouts:
Isolation Valve
Mixing Valve
Float Type Automatic
Air Vent (Bottle Valve)
Shower Handset
Check Valve
Pressure Switch
Pressure Accumulator
Ball Valve
Fixed Shower Head
DHW Domestic Hot Water
Fault
System Layout
Figure 2

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Cistern
DHW
Pump
Optional Check Valve
Other hot water
services
System Layout with High Level Pipework
Figure 3
Other hot water
services Pump
Cistern
DHW
Unsuitable System Layout
Figure 4

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2. Electrical
WARNING: THIS APPLIANCE MUST BE EARTHED.
All electrical installations must comply with current IEE regulations and be undertaken
by a qualified person.
2.1. The power to the pump should be through a double pole, switched, fused
connection unit or equivalent with a 5A fuse (Refer to Figure 6), the contact
separation in each pole should be at least 3mm. A cable with a minimum core
area of 0.75mm2should be used from the fuse to the pump.
2.2. Remove the terminal cover (single screw) and connect the electrical supply
and, only if necessary, connect the momentary action switch to the
appropriate terminals (Refer to Section 2, Operation):
L = Brown, N = Blue, E = Yellow/Green, FS = Flow Switch and External
Switching. (Refer to Figure 6). Ensure that the cable gland nut is tightened
to provide strain relief.
Other hot water
services
DHW
Cistern
Pump
Unsuitable System Layout
Figure 5

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2.3. Cross bond the inlet and outlet pipework, using a minimum 6mm2 cable
and bonding clamps (Refer to Figure 7). Plastic pipes do not require bonding.
Blue Brown
Terminal Block
Gland Nut
Mains Cable
Cable to Flow
Switch (FS)
E L N F/S
Brown
Brown
Blue
Blue
Brown Blue
Connection Unit
Fused 5A
Optional
Momentary
Action Switch
F/S
Wiring Diagram
Figure 6

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Outlet
Inlet
Pipe Bonding Details
Figure 7

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Section
6Commissioning
1. Commissioning
1.1. Proceed with caution due to the risk from hot water and scolding.
1.2. Ensure that the pump is electrically isolated.
1.3. Ensure that all the isolating valves are fully open and that the pump chamber
is fully flooded.
THIS PUMP MUST NOT BE RUN DRY. IF IT IS, SEAL AND BEARING
DAMAGE MAY OCCUR.
1.4. Open the shower fully. Water should flow from the outlet under the pressure
of gravity. Leave the outlet open for a short period of time to allow the air to
be expelled from the system. Turn off the shower and check the pump,
shower and the interconnecting pipework for leaks.
1.5. If no water comes out of the outlet, then the system may be airlocked or the
shower may be fitted in a negative head situation. Refer to Section 7,
Maintenance: "Fault Diagnosis" or Section 2, Operation.
1.6. Switch on the power to the pump.
1.7. Open the shower valve and check that the pump has operated automatically.
1.8. The flow rate must be at least 1.4 l/min for the flow switch to operate.
1.9. If the pump is not operating correctly repeat the commissioning procedure,

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Section
7Maintenance
1. Fault Diagnosis
Read the section "Important Safety Information" first.
Providing the shower pump has been correctly installed and is operated in accordance
with the instructions contained in this guide, difficulties should not arise. If any
maintenance is required then it must be carried out by a competent tradesperson for
whom the fault diagnosis and maintenance instructions are provided. Before replacing
any parts ensure that the underlying cause of the malfunction has been resolved.
1.1. Pump does not start
1.1.1. Check adequate gravity flow (1.4 l/m).
Isolate power and water and check:
1.1.2. Supply fuse, mains supply and the fused connection unit.
1.1.3. Free operation of the flow switch, fitted externally in the outlet vertical
pipe of the pump, with the Inlet at the bottom.
1.2. Pump does not stop after the water flow has ceased
Isolate power and water and check:
1.2.1. Check that the flow switch is fitted correctly (Refer to Section 5,
Installation).
1.2.2. Free movement of magnetic float within flow switch.
1.2.3. Any external switching connected operating correctly.
1.3. Pump operation occurs momentarily
If pump operation occurs momentarily, particularly when other hot water
services that are not on the pumped circuit are used, or an on/off pulsating
operation occurs when the shower is turned off, check:

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1.3.2. Fit check valve onto pump outlet after flow switch to prevent water
surging in the pipe work. This may increase the pressure required to
start the pump (Refer to Figure 3).
1.4. Flow starts adequately and drops after a short time
Check:
1.4.1. Sufficient stored cold water.
1.4.2. Pipe work that is prone to air-locking should be rerouted to be self
venting when not in use. Float type Automatic Air Vents are, in
general, NOT advisable for pump inlet pipe work, as a negative pump
pressure will allow air to be sucked in through Automatic Air Vents.
The pressure at the desired vent position can approximately be
determined using the Mira green book ‘A Guide to Domestic Pumped
Shower Systems’, to check whether it remains positive under
dynamic conditions.
1.3.1. There are no air-locks in the pump outlet pipe work. These will cause
water movement through the pump by compression of the air. Reroute
the pipe work or fit float type automatic air vents at air collection points.
(Refer to Figure 3).

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1Spare Parts
Appendix
226.08 Resilient Pad
872.06 Flow Switch
226.08
872.06