EHC Fusion MERCURY COMBI User manual

The Fusion Range of Boilers
the ultimate solution for central heating
INSTALLATION
&
TECHNICAL MANUAL
If you require any further assistance:
Telephone: [phone]
Fax: [phone]
E-mail: [email protected]
or visit our website www.electric-heatingcompany.co.uk
Fusion
MERCURY
COMBI

2
GB
INTRODUCTION
Please read and follow the installation and operating instructions
carefully, to ensure the long life and reliable operation of this
appliance.
The Electric Heating Company may make minor changes
if necessary in the appliance that will not be shown in the
operating instructions, so long as the main features of the boiler
remain the same.
All boilers come with a 24 month warranty that covers all
defects originating from faulty materials and workmanship in the
manufacture of the boilers.
The warranty covers the replacement of any faulty parts and
labour costs.
The warranty will not cover any damage to the boiler from poor
or incorrect installation work.
The warranty will not cover any call out charges that have not
been organised by the Electric Heating Company Ltd.
The warranty will not cover water leaks into the boiler. All
plumbing joints must be checked.
The warranty card must be completed and sent back to The
Electric Heating Company as soon as possible for product
registration ,alternatively the boiler can also be registered online
when you visit the link below.
https://www.electric-heatingcompany.co.uk/support/ warranty-
registration/
This appliance can be used by children aged from 3 years and above and persons with reduced physical, sensory or
mental capabilities or lack of experience and knowledge if they have been given supervision or instruction concerning
use of the appliance in a safe way and understand the hazards involved.
Children shall not play with the appliance.
Page Contents
INTRODUCTION 2
PREPARATION 3
INSTALLATION 4
BOILER DIMENTIONS & PLUMBING SCHEMATIC 5
COMMISSIONING 6
ELECTRICAL CONNECTIONS AND CONTROLS 7
BOILER INTERNAL LAYOUT 8
CONTROL PANEL WIRING 9
EXTERNAL WIRING 9
BOILER WIRING 12/15 kW 10
INTERNAL BOILER WIRING 19/26 kW 11
USER INSTRUCTIONS 12
ADVANCED SETTINGS 14
FAULT FINDING 15
TECHNICAL SPECIFICATIONS 16
Mercury
Combi

3
GB
PREPARATION
Instructions and Building Regulations
This appliance must be fitted in accordance with the following
instructions.
The Local Building Regulations
The Building Regulations
The Building Standards, (Scotland-consolidated) Regulations.
Local water bylaws. British Standards- code
of practice
BS EN 12828
Heating systems in buildings. Design for water-based heating
systems.
BS EN 12831
Heating systems in buildings. Method for calculation of the design
heat load
BS EN 14336
Heating systems in buildings. Installation and commissioning of
water based heating systems
BS7671
Requirements for electrical installations. IEE Wiring Regulations.
Seventeenth edition.
BS EN 13831
Closed expansion vessels with built-in diaphragm for installation
in water
C.O.S.H.H.
Materials used in the manufacture of this appliance are non-
hazardous and no special precautions are required when fitting
or servicing this appliance.
PREPARATION
1. Load Check
A load check should be taken into consideration when installing
high output boilers.
2. Boiler location
The boiler must be fitted on a wall that will provide an adequate
fixing, and should be fitted in a location that the boiler and
pipe-work are not subject to frost and damp conditions.
3. Central heating (design & installation)
Detailed recommendations are given in BS EN 12828, BS 6700
and CP 342-2
Pipes forming part of the useful heating surface should be
insulated to prevent any potential heat loss or frost damage
(BS 6700).
Drain valves should be fitted at the lowest point of the system
pipe work in an accessible position.
Drain valves should be in accordance with BS 2879 and copper
tube to BS EN 1057. is recommended.
LOCATION
The boiler can be installed in almost any location within a domestic
or commercial property, however consideration should be given to
future maintenance. Never leave the boiler switched off if there is
danger of having temperatures below 0°C in the room where it is
located.
We recommend that a minimum clearance of 450 mm should be
allocated for the removal of the front cover and adequate access
to the boiler plumbing and the internal electrical connections.
A 50 mm allowance should be made at either side of the boiler
to allow free flow air into the boiler case and allow access to
screws on the boiler case.
THE BOILER MUST BE INSTALLED IN THE UPRIGHT POSITION,
FAILURE TO DO SO WILL INVALIDATE THE WARRANTY

4
GB
INSTALLATION
1. General
Mercury boilers must be installed by a professional plumber or
heating engineer. All Electrical works must be carried out by
a fully qualified electrician in accordance with the current
revision of BS7671 wiring Regulations.
The Electric heating Company Ltd will not be held responsible
for faulty installations which are performed by unqualified
tradespeople.
2. Pipe Connections
Mercury boilers Plumbing connections are of the compression
type. (22mm for Flow & Return & 15mm for Hot & Cold).
3. Case Removal
Remove outer screw at the bottom of the boiler and pull the front
cover outwards and upwards taking care to remove internal earth
connection. Earth connections must be re-connected before the
boiler case is re-installed.
4. Isolation Valves
We recommend that lever isolation valves are fitted on the
flow and return pipework. Such valves must be „full bore” and
not „ball valves”. The installation of “ball valves” will reduce
the recommended flow through the boiler that could promote
premature boiler shut-down.
5. Mains Water inlet
We recommend that a lockshield stopcock is fitted on the mains
inlet of the boiler to allow you set the recommended flow rate.
(Flow rates can be found in the technical table within this manual)
When the boiler is fitted in hard water areas, a water softener
must be used. Note: Salt softeners must not be used to fill the
heating system.
6. Auto air vents
An auto air vent is integral within the boiler however an additional
auto air vent must be fitted at the cylinder coil if the boiler is being
used for central heating and domestic hot water.
7. Boiler Sizing
Calculate the „space heating” requirements in accordance with BS
EN 12831 and BS EN 14336. If the boiler is to heat the domestic
hot water, an additional allowance of 3kW (10,239 Btu’s) should
be made to the ‘space heating’ calculation.
8. Insulation
Where practical, and if at all possible, we recommend that all
pipe-work be insulated, in particular the pipe-work within a boiler
cupboard. This is to reduce heat loss and reduce high cupboard
temperatures from exposed pipe-work. (BS 6700).
9. System Design
Allowance should be made for a radiator to be installed within
the heating circuit and locked open. This will be located in the
room that has the room thermostat installed.
To comply with building regulations, Part L and Part J (in Scotland),
room and cylinder stats must be fitted.
Water Connections, Provisions must be made for the replacement
of water lost from the heating system (sealed systems).
Reference should be made to BS EN 14336 for the method of
filling and make up of water. There must be no direct connection
between the boilers central heating system and the main water
supply. When mains water is required to fill the system directly,
all local water bylaws must be observed, and any connection
made must be disconnected after use.
10. Flushing
The system must be flushed to within 10% of mains water PPM to
ensure that no debris is trapped in the system as this may result in
boiler failure. Where existing radiators and pipe-work are utilized
a power flush must be carried out .For further guidance please
see - Commissioning section on page 6.
11. System pressures
All boilers are tested to 4.0 bar. The normal working pressure
of the boiler should be set to approx 1.0 / 1.5 bar. All sealed
systems should comply with the relevant building regulations and
standards, including BS EN 13831 Specification for Expansion
Vessels.
12. System types
The Fusion Mercury Combi Boilers can be used in various heating
designs including underfloor systems. When the boiler is used
with an underfloor manifold, the manifold must be of the type that
has a thermostatic mixing valve fitted to protect the floor surface.
For standard radiator systems we recommend the use of
thermostatic radiator valves on all radiators except in the room
that has the wall thermostat fitted. This radiator should be fitted
with lock-shield valves and left in the fully open position.
Systems should be designed to meet the current building
regulations in force at the current time.
13. Hanging the Boiler
Hang the boiler in a vertical position using the mounting bracket
and fixing screws provided. Make sure the boiler has the minimum
recommended clearances as mentioned within this manual.
Connect the boiler to a heating system that is equipped with full
bore isolation valves and external magnetic filter.

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GB
BOILER DIMENTIONS & PLUMBING SCHEMATIC
260mm
406mm
inlet
CH
outlet
CH
inlet
DHW
outlet
DHW
min
150mm
min.
60mm
min.
60mm
120mm 50mm
5mm
Width 451mm
Height 690mm
Depth 258mm
M
M
F - Magnetic Filter
ZK - Full Bore Isolation Valves
Z - Drain Valve
G - Radiator
ZT/ZP - TRVs
RP - Programmer / Thermostat Locksheild
MS - Stop Cock (To regulate Flow)
Note:
We don’t recommend the using single phase
boilers to fill baths due to the lower flowrates
produced by them.
Plumbing Schematic
External Weather Sensor

6
GB
COMMISSIONING
IMPORTANT:
Make sure that all plumbing connections are tight before filling the boiler and heating system.
Bleeding DHW pipework.
1. Open the DHW tap outlets one at a time.
2. Slowly open the mains Stopcock feeding the DHW circuit of the boiler, until the air has been removed from the hot water pipework,
close each tap after water starts to flow.
3. Adjust the DHW flow rate.
4. Open one of the tap outlets and adjust the flow rate by slowly closing the (MS) regulator valve to the recommended flow rate for your
boiler size. Refer to the technical table shown on page 17.
5. After the boiler has been electrically wired and tested, you can now turn on the electrical power supply to the boiler.
6. Make sure the programmer is not calling for heat at this stage.
Note: When the boiler is fitted in hard water areas, a water softener must be used. Salt softeners must not be used to fill the heating
system.
Filling the Heating Circuit:
1. Turn on the electrical power supply to the boiler.
2. Make sure the programmer is not calling for heat at this stage.
3. Connect the filling loop and tighten.
4. Make sure that all connections are tight before filling.
5. Open the filling loop and allow the system to start filling.
6. Press the right arrow key on the boiler control panel until the A (bar) led is illuminated.
7. fill the system to 1,5 bar, then start to purge the radiators until all the air is out the system.
8. This will have to be repeated several times to fully purge the system re-filling as you go.
System protection:
Note: THE HEATING CIRCUT MUST BE FLUSHED IN ACCORDANCE TO BS 7593
Failure to protect the system will invalidate the manufacturer’s warranty.
1. Fill the system with cold mains water to the recommended pressure 1.5 bar and check for leaks, then drain the system thoroughly
making sure all drain cocks are fully open and that the system is completely drained.
2. Add Fernox F3 cleaner to the system at the furthest point from the boiler, this is to allow the substance to fully dilute throughout the
system. If you are unsure of the correct dose rate, contact Fernox on 03301007750 for advice.
3. Re-fill the system and circulate the F3 cleaner prior to the boiler being fired up. Commission the system in the normal way. The
cleansing agent must be in the system for a minimum 1 hour with the system running at normal operating temperature. A longer period
of time would be more beneficial to the cleansing process especially if excess flux was used or is an old system. F3 cleaner can be left
in the system for up to a maximum of one week running on a normal heating cycle. (We recommend that existing systems are power
flushed as per BS 7593 and PAS33 regulations)
4. Drain and flush the system thoroughly to remove the cleaning agent and any debris or contaminants. This is a critical part of the
cleaning process and must be carried out correctly. Use a rinse test meter (TDS), such as the Fernox CTM. The reading must be within
10% of the mains ppm value.
5. After the system has been thoroughly flushed and TDS readings are within 10% you can now add Fernox F1. This will protect against
the formation of scale, corrosion and microbiological growths. It is crucial however, that for the protector to work correctly, the system
must be properly cleansed and flushed.
6. Now attach the label included within the Fernox F1 packaging completed and attached adjacent to the boiler. We recommend inhibitor
levels are checked on an annual basis (usually during the service) or sooner if the system content is lost. This should be carried out
using a Fernox inhibitor Test Kit. Fernox Technical Service Help line on 0870 870 0362 for further assistance.

7
GB
Electrical „mains”connection
Boiler Protection The recommended protection for hard wired
boilers are as follows:
Model No Boiler size Protection (per phase)
MER26KW 3ph 25,8 kW BOILER 3x40 AMP Protection
M ER19KW 3ph 19,5 kW BOILER 3x32 AMP Protection
MER15KW 14.4 kW BOILER 80 AMP Protection
MER12KW 12 kW BOILER 63 AMP Protection
External Controls
We recommend the use of the EHC SINGLE
CHANNEL PROGRAMMER and EHC ROOM THERMOSTAT
Note: This control method is recommended by BEAMA
(The association of Control Manufactures) in order to comply
with the current Building Regulations.
CURRENT IEE BS7671 WIRING REGULATIONS.
ALL ELECTRICAL CONNECTIONS MUST BE MADE BY A
QUALIFIED ELECTRICIAN.
Load check must be taken into consideration when installing high
power boilers. This will be carried out by a qualified electrician.
There may be an additional requirement to upgrade the incoming
main fuse supplying the property if other high power devices are
used within the property. E.g Electric Showers. If an electric shower
is present we recommend that a Shower Sensor is installed within the
system. This will cause an interrupt to the boilers control signal when
the shower is in use. It will disable the boiler protecting the electrical
system from overload.
All boilers Must be protected with a 30mA double pole RCD with
a minimum of 3mm contact separation accompanied by a suitably
rated MCB. If the boiler is not fitted local to the meter position then an
additional isolation switch must be fitted local to the boiler for each
supply. If the property is supplied by a rural power supply or prone to
lightening strikes & power cuts it is recommended to install a suitable
surge protection device to the boiler supply. This will reduce the risk
of damage to the boiler electronics during these events.
THIS APPLIANCE MUST BE EARTHED.
All pipe-work must be earthed in accordance with the IEE BS7671
Wiring Regulations.
After completion of all electrical works, an electrical safety check
should be carried out i.e. short circuit, earth continuity, resistance to
earth and polarity check, and all relevant Test Certificates completed
and issued to the customer.
Never open the front cover of the boiler until all power supplies to the
boiler have been disconnected.
ELECTRICAL CONNECTIONS
The boiler connections are clearly marked inside the boiler L N E
(24hr LIVE).
The 24hr live is the permanent Feed connection to the boiler from
the mains supply. External controls will require an independent
fused spur supplied from the same consumer unit & protected by the
same RCD as the boiler itself. Where a single phase boiler is installed
within a 2 Phase or 3 Phase installation the control circuit should
also be supplied by the same phase as the boiler. The control circuit
should be protected by a 6Amp.
MCB. The Boiler & control circuit RCD should be independent of all
other domestic circuits. The boiler supply cable should be calculated
by the means of a cable calculation in accordance with BS7671 by
a suitably qualified electrician.
ELECTRICAL CONNECTIONS AND CONTROLS

8
GB
INSTALLATION
BOILER INTERNAL LAYOUT
3
2
4
6
10
12
20
19
1
7
1
6
15
14
13
11
9
7
1
5
18
8
1 - Wall Bracket
2 - Main Electrical Connection
3 - WT3 Thermal cut-out
4 - PSK Controller
5 - Return Temp Sensor
6 - Thermal WTC3
7 - Power Board
8 - Water Heater PCB
9 - Smart Pump
10 - DHW Heat Exchanger
11 - Heat exchanger
12 - DHW flow Sensor
13 - Flow Temp Sensor
14 - PRV
15 - Flow Outlet
16 - Return Inlet
17 - Pressure Sensor
18 - E
xpansion pipe
19 - DHW outlet
20 - Mains Water Inlet

9
GB
CONTROL PANEL WIRING
(Volt Free)
SAFETY NOTE: „RP”, and „NA”are signal conductors only. DO NOT CONNECT ANY VOLTAGE to
these as this will damage the boiler and invalidate the boilers warranty!
Shower Sensor connection
(Optional)
External Volt Free Call Signal
(Programmer / Thermostat
F
F
RP
RP
T
T
e
e
xt.
xt.
PUMP
PUMP
External Weather Sensor
Note:
If the weather sensor is not used
it will have to be disabled in the
advance settings.
Pump Connections
(factory made)
EXTERNAL WIRING

10
GB
black
blue
brown
ZG - heating element of boiler ZM - power board of boiler MSK - control module of boiler M1 - circulating pump of boiler P - pressure sensor Tin - inlet temperature sensor of boiler Tout - outlet temperature sensor of boiler F1 - safety temperature limiter XP - connection block Kp - cover Kd - base
PE - Master supporter base E1 - heating element of water heater ZMP - power board of water heater MSP - control module of water heater Twej - inlet temperature sensor of water heater Twyj - outlet temperature sensor of water heater BV - flow sensor of water heater F2 - thermal-pressure cut-off of water heater XP - connection block heating element of water heater Twyj - outlet heater
INTERNAL BOILER WIRING 12/15 kW

11
GB
INTERNAL BOILER WIRING 19/26 kW
black
blue
brown
ZG - heating element of boiler ZM - power board of boiler MSK - control module of boiler M1 - circulating pump of boiler P - pressure sensor Tin - inlet temperature sensor of boiler Tout - outlet temperature sensor of boiler F1 - safety temperature limiter XP - connection block Kp - cover Kd - base
PE - Master supporter base E1 - heating element of water heater ZMP - power board of water heater MSP - control module of water heater Twej - inlet temperature sensor of water heater Twyj - outlet temperature sensor of water heater BV - flow sensor of water heater F2 - thermal-pressure cut-off of water heater XP - connection block heating element of water heater Twyj - outlet heater

12
GB
USER INSTRUCTIONS
CONTROL PANEL
Control Panel Key
A - pressure [bar]
B - flow [l/min]
C - power [kW]
D - temperature [°C]
E - digital display
F - indicator of room thermostat and
heating activity (CH)
G - indicator of pump and flow activity
H - indicator of weather compensation
controller
I - inlet temperature indicator
J - outlet temperature indicator
K - indicator of activity (CH)
L - indicator of instantaneous water
heater
M - control buttons
FI
INDICATOR STATUS DETAILS
ON room thermostat allows the boiler to heat
OFF required temperature has been reached (boiler doesn’t heat)
flickering master appliance doesn’t allow to heat (NA entry is open) OR outside temperature sensor is above the set
CH shutoff value in advance settings.
ON pump is active, a proper flow rate of medium has been reached
flickering lack of flow or insufficient flow rate of medium (failure condition), a heating elements are off,
red heating on- boiler's CH mode
green
desired temperature has been reached
Device in domestic hot water heating mode (icon in red)
temp. in CH system is lower than required but the required room temperature has been reached, RP
entry is open, or room thermostat is blocked
OFF summer mode on
red Device operates in domestic hot water heating mode.
A flickering installation pressure is not sufficient (below 0,5 bar), heating is blocked, pump is inactive
Ehorizontal
dashes parameter out of range, temp. sensor failure or fault in domestic hot water module.
I or J flickering relevant temperature sensor failure
+D+K ON preview of outside temperature

13
GB
USER INSTRUCTIONS
1. Start up
1. Check if required pressure has been set within the installation
(see section “Technical Data”). In order to check use or
button when control panel is in Stand-by mode.
If the bar L.E.D flashes on the control panel this indicates that
the installation pressure is low. This does not apply to open
vent/gravity fed installations.
2. Set the pump at constant mode (see section “Advanced
settings”).
3. Switch the boiler on (press button).
4. Check if the appropriate medium flow rate has been reached (the
„G” indicator is on with a constant light). The pump should vent
itself after a short working time, however, if necessary, vent the
pump in the following way:
• close the flow isolation valve under boiler,
• set the pump on the highest efficiency
(see section “Advanced
settings”)
,
• leave the boiler with the pump running for 15-30 s.
• open the flow isolation valve under boiler.
5. Switch the boiler off (press and hold button for 3 seconds).
6. Set the pump to automatic mode (see section “Advanced
settings”).
7. Set parameters of heating curve adjusted to the building
(heating curve coefficient and offset) - see section “Advanced
settings”. Reset of the curve slope so that it switches off weather
compensation and starts boiler’s operation in accordance with
manual adjustments of the installation.
8. Switch the boiler on (press button).
9. Set the programmer / room thermostat to call for heat
2. Boiler Operation
Stand-by mode
In stand-by mode the pump is activated everyday for 2 min, which
prevents seizure of the pump. To switch between stand-by mode and
summer/winter mode press and hold the power button for 3 seconds.
Stand-by is indicated by briefly showing on the display followed
by the display turning blank.
Pressing or buttons displays parameter of installation
pressure. After 1 min of inactivity the display becomes blank again.
Pressing button in the stand-by mode shifts boiler’s operation to
winter or summer mode depending on the valid settings adjusted before
activation of stand-by mode.
Winter mode
Winter mode is active when the icons are active.
In winter mode (main view) the control panel displays icons
describing the current device operation. The digital display shows
the flow temperature of the central heating system or domestic water
temperature, if heating conditions are present.
Pressing button will show the current parameters and device
settings in the following order:
- domestic water temperature setting (indicators L and D). Using
buttons or you can change the domestic water setting
value,
- domestic water temperature at the inlet (indicators I, L, D),
- domestic water temperature at the output (indicators J, D and
L),
- value of water flowing through the heater (indicators L and B),
- current power consumed by the water heater (indicators C and
L),
- CH medium temperature adjustment (indicators K and D),
indicator H is on when weather compensation regulator is
active (advanced settings). Indicator H flashes when there is
no possibility to determine installation temperature due to the
lack or failure of outside sensor- the boiler shifts to manual
adjustments. Pressing or buttons when heating medium
temperature is indicated on the display results in heating
medium value change. Note, it works only when weather
compensation regulator is switched off (advanced settings -
parameter C=0) or when there is no outside sensor,
- inlet temperature CH (indicators I, K and D),
- outlet temperature CH (indicators J, K and D),
- outside temperature (indicators F, D, K),if the weather
compensation regulator is disabled, the parameter is ignored.
In case of a failure of the external sensor and the weather
compensation controller is turned on, are shown on the digital
display characters such as “---”
- flow of the medium through the boiler (indicators K and B),
- pressure in CH installation (indicators K and A),
- current power charged by boiler (indicators K and C).
If the control panel is in the preview / parameter setting mode,
pressing the button or if the keyboard is not used for 1 minute, it
will return you to the main view.
If the control panel is in the main view, short press the button
to enter to summer mode.
Summer mode
Summer mode is active when the icon is active and the icon
is inactive.
In summer mode (main view) the control panel displays icons de-
scribing the current device operation. Digital display shows the output
temperature of domestic water,
if heating conditions exist.
Pressing button shows preview of current parameters and device
settings in the following order:
- domestic water temperature setting (indicators L and D). Using
buttons or you can change the domestic water setting
value,
- domestic water temperature at the inlet (indicators L, I, D,
- domestic water temperature at the output (indicators J, D and
L),
- value of water flow through the heater (indicators L and B),
- current power consumed by the water heater (indicators C and
L),
If the control panel is in the preview / parameter setting mode,
pressing the button or if the keyboard is not used for 1 minute, it
will return you to the main view.
If the control panel is in the main view, short press the button
to enter to winter mode.

14
GB
To enter Advanced settings the boiler must be in Stand-by
mode. Stand-by mode is shown by a cyclic, short display of the
“off” message on the display. If the controller is in winter mode
or summer mode, it must be put into Stand-by mode by
holding down the power button until a long beep is heard and
the message “off” is briefly shown on the display.
If the controller is in Stand-by mode, press and hold the button
until the appearance of a long beep and the message SET on
the display.
To select parameter press to change the value press
or :
Weather Compensation Settings (curve coefficient):
C= 4-25 (weather compensation active based on curve
selected)
C= 0 (weather compensation deactivated, manual user
temperature selection activated)
Heating Curve Offset:
O= -9°C ÷ 9°C
Outside Temperature Threshold:
0°C ÷ 25°C threshold set-point of outside temperature where
CH is automatically switched off.
Pump Working Mode:
PA – Automatic Operation
PC – Constant operation
Pump Efficiency (Head):
E3.0 = 3.0m
E4.0 = 4.0m
E5.0 = 5.0m
E6.0 = 6.0m
E7.0 = 7.0m
E7.5 = 7.5m
Pump Pressure Mode:
Constant pressure difference (pressure indicator on).
Variable pressure difference (pressure indicator flashing).
CH Pressure Sensor:
1 = Pressure Sensor Active (On)
0 = Pressure sensor deactivated (Off – Open Vented Systems
Only)
Maximum Set-point of CH Temperature:
20°C ÷ 85°C
Kw Consumption History:
Read-only display of boiler kilowatt consumption.
To exit the “Advance Settings Menu” press and hold the power
button for 3 seconds to re-enter stand-by mode, pressing the
power button again will return the boiler to winter/summer mode
respectively.
ADVANCED SETTINGS
Heating curve coefficient.
Offset of the heating curve for c=12
c=4
20,0
30,0
40,0
50,0
60,0
70,0
80,0
90,0
-20-1001020
˚C
˚C
c=6
c=8
c=10
c=12
c=14
c=16
c=18
c=20
c=22
c=24
o = +9
c = 12 o = 0
o = -9
20,0
30,0
40,0
50,0
60,0
70,0
80,0
90,0
-20-1001020
˚C
˚C

15
GB
FAULT FINDING
Symptom Reason Action
Indicators on
control panel are off lack of device's power supply.
check parameters of power network and
fuses
contact authorised service
A indicator Flashing
insufficient pressure (below 0,5 bar)
shift the controller to the pressure view,
increase pressure within the installation to
required level (1.5bar Cold)
pressure sensor failure
switch the controller to pressure preview, if
display E indicates "--" contact authorised
service
G indicator flickers
pump blocked or seized unblock pump's rotor
lack of medium's flow through the boiler-
boiler's blockage
air locked central heating system, vent the
installation, pump and boiler & re-set pressure
check water quality of CH installation and
clean the filter
failure of pump's power supply contact authorised service
failure of pump or flow sensor contact authorised service
F indicator is off (in winter mode), room
thermostat indicates heating on
check room thermostat is providing
continuity across RP connection
check programmer/thermostat. linked out RP
& NA if no response, change PSK Controller
failure of electronic module contact authorised service
I indicator flickers failure of outlet temp. sensor, heating
blockage contact authorised service
J indicator flickers failure of outlet temp. sensor, heating
blockage contact authorised service
F indicator flickers and the boiler doesn't
work
failure of installation that connects master
appliance or shower sensor check connecting installation
outside temperature sensor is above the set
CH shutoff value in advance settings.
boiler will reactivate once outside tempera-
ture drops below set value
Device does not switch to domestic hot
water heating mode.
failure of electronic module contact authorised service
H indicator flickers failure of external temp. sensor contact authorized service
L indicator flickers (red) failure of cylinder water temp. sensor contact authorized service

16
GB
TECHNICAL SPECIFICATIONS
Boiler range MERCURY 12kW
(MER12KW)
MERCURY 15kW
(MER14,4KW)
MERCURY 19kW
(MER19,5KW)
MERCURY 26kW
(MER25,8KW)
Pipe entry from boilers Bottom Bottom Bottom Bottom
Central heating flow & return pipes 22 mm 22mm compression connections
Min water pressure 1 bar
Max water pressure 3 bar
Expansion vessel
6 lt.
Maximum system water volume about 60 litres at initial system pressure 1,5 bar
Vessel charge pressure 1,5 bar
Safety Class IP22
Overall dimensions(height x width x
depth) 690 x 451 x 258
Dry weight 19 kg
Electrical supply 240V 1ph 50Hz
415V 3ph 50Hz
Load/current 50,0 Amp. 60,0 Amp. 3 x 26,9Amp. 3 x 35,9Amp.
Minimum permitted cable diameter 16 mm25 x 6 mm2
Heating output 40945 Btu 49134 Btu 61418 Btu 85303 Btu
Max. temp setting 85°C
Min temp setting 20°C
Overheat Protection 100°C
Pump included Yes
Recommended Pump settings Factory set to Max , See page 14 for settings
Required Protection 63 Amp. 80 Amp. 3 x 32Amp. 3 x 40Amp.
The maximum allowed network imped-
ance 0,24 Ω0,22 Ω0,27 Ω0,37
ERP Rating
D
D
D
D
Water Heater
Efficiency (at Δt = 30°C and water pressure
at 0,4 MPa) 5,8 l/min 6,9 l/min 9,2 l/min 12,4 l/min
Pressure in the water mains 1 ÷6 bar
Activation point (min. rate of flow) 2,5 l/min
Temperature
adjustment range
NORMAL mode 30 ÷ 60 °C
SHOWER mode 30 ÷ 55 °C
Water fittings 15mm compression connections
The minimal resistivity of water at 150C is 1100 Ωcm.
Maximum Water Hardness 200ppm (softener to be used where value is exceeded)
*Stated cable sizes are the minimum permitted for boiler installations, The Installer is solely responsible for verifying & selecting the correct
diameter cable based on the characteristics of the installation by means of a cable calculation set out in BS7671.

17
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Electric Heating Company Ltd
Unit 40, Block 5
Third Road
Blantyre Industrial Estate
Blantyre
Glasgow
G72 0UP
Tel: [phone] Fax: [phone]
www.electric-heatingcompany.co.uk
(Waste Electrical & Electronic Equipment)
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This marking shown on the product or its literature, indicates that it should not be disposed of
with other household wastes at the end of its working life.
To prevent possible harm to the environment or human health from uncontrolled waste
disposal, please separate this from other types of wastes and recycle it responsibly to promote
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