Ariston GENUS HE 35 Plus User guide

GENUS HE 35 Plus
BFFi
Installation and
Servicing
Instructions
Type C Boilers
G.C.N: 47-116-57 (35 kW)
LEAVE THESE
INSTRUCTIONS WITH THE
END-USER
GENUS
HE 35
Plus
Country of destination GB IE

2
1. General Information
2. Control Panel
3. How to Use
4. Anti-Frost Device
5. Maintenance
6. Trouble Shooting
7. Filling Instructions
8. Time Clock
8.1 Setting the Mechanical Clock
8.2 Setting the Digital Clock
9. General Information for the Installer
9.1 Overall View
10. Installation
10.1 Delivery
10.2 Reference Standards
10.3 Siting the Appliance
10.4 Clearances
10.5 Overall View
10.6 Mounting the Appliance
10.7 Electrical Connection
10.8 Gas Connection
10.9 Water Connections
11. Connecting the Flue
11.1 Fitting the Coaxial Flue (Ø 60/100 mm -
Horizontal)
11.2 Fitting the Coaxial Flue (Ø 60/100 mm -
Vertical)
11.3 Fitting the 5” Flue (Ø 80/125 mm - Vertical)
11.4 Fitting the Twin Pipe (Ø 80/80 mm)
12. Electrical Connections
13. Electrical System Diagrams
14. Water Circuit Diagrams
15. Commissioning
15.1 Initial Preparation
15.2 Completion
15.3 Removal and Fitting of the Case - Servicing
15.4 Pressurisation
15.5 Commissioning
15.6 Settings
15.7 Operating Faults
TABLE OF CONTENTS
16. Gas Convertion
17. Maintenance
18. Servicing Instructions
18.1 Replacement of Parts
18.2 To Gain General Access
18.2.1 Removing the front panel
18.2.2 Removing the control panel
18.3 Access to the Control System
18.3.1 Removing the main PCB
18.3.2 Removing the display PCB
18.3.3 Removing the fuses
18.3.4 Removing the time clock
18.4 Access to the Combustion Chamber
18.4.1 Removing the combustion chamber front panel
18.4.2 Removing the air gas assembly
18.4.3 Removing the burner
18.4.4 Removing the detection electrode
18.4.5 Removing the ignition electrode
18.4.6 Removing the fan
18.4.7 Removing the gas valve
18.4.8 Removing the heat exchanger
18.4.9 Removing the spark generator
18.5 Access to the Water Circuit
18.5.1 Drain down
18.5.2 Removing the 3 way valve
18.5.3 Removing the heating return filter
18.5.4 Removing the by-pass
18.5.5 Removing the pressure relief valve (3 bar)
18.5.6 Removing the pressure relief valve (7 bar)
18.5.7 Removing the temperature & pressure relief
valve (7 bar)
18.5.8 Removing & cleaning the condensate trap
18.5.9 Removing the pressure gauge
18.5.10 Removing the pump
18.5.11 Removing the heating expansion vessel
18.5.12 Removing the DHW expansion vessel
18.5.13 Removing the overheat thermostat
18.5.14 Removing the temperature sensors (N.T.C’s)
18.5.15 Removing the tank temperature sensor
18.5.16 Removing the water pressure gauge
18.5.17 Removing the flow switch
18.5.18 Removing the DHW temperature sensor
18.5.19 Removing the non return valve
18.5.20 Removing the plate heat exchanger
18.5.21 Removing the tank
19. Fault Finding Guide
20. Short Spares List
21. Technical Information

3
These instructions are suitable for the GENUS HE 35 Plus boilers :
Do not forget the Log Book!
MTS supports Benchmark, the heating industry code to ensure the correct installation, commissioning and servicing of
domestic central heating systems.
To The Householder
Make sure you have a completed Log Book for your boiler. This provides a record of the commissioning of your boiler.
It contains important information about your particular installation that may be required by service engineers. The Log Book will
also provide contact details for the installer should you need guidance in the use of this appliance or if there are any problems.
As with your car, your boiler will work more reliably and efficiently if regularly serviced. We recommend an annual service
check. The service history of the appliance will be recorded on the Log Book.
In the unlikely event of any problems with your boiler or system you should first contact your installer. If your installer cannot
resolve the problem he should telephone our national service helpline.
A charge may be made if MTS Service is called out to resolve a non-product related fault.
Your statutory rights are not affected.
CUSTOMER CARE
MTS, as a leading manufacturer of domestic and commercial water heating appliances is committed to providing high quality
products and a high quality after sales service.
Advice on installation or servicing can also be obtained by contacting the MTS Technical and Customer Service Departments
at High Wycombe.
TECHNICAL DEPARTMENT CUSTOMER SERVICE DEPARTMENT
Tel: [phone] Tel: [phone]
Fax: [phone] Fax: [phone]
GUARANTEE
The manufacturer’s guarantee is for 2 years from the date of purchase. The guarantee is invalidated if the appliance is not
installed in accordance with the recommendations made herein or in a manner not approved by the manufacturer. To assist us
in providing you with an efficient after sales service, please return the guarantee registration card enclosed with the boiler
without delay.
CAUTION
In the United Kingdom, installation, start-up, adjustments and maintenance, must be performed by a competent person only, in
accordance with the current Gas Safety (Installation & Use) Regulations and the instructions provided.
In the Republic of Ireland, the installation and initial start up of the appliance must be carried out by a Competent Person in
accordance with the current edition of I.S.813 “Domestic Gas Installations”, the current Buidling Regulations, reference should
also be made to the current ETCI rules for electrical installation.
All CORGI registered installers carry a CORGI ID card, and have a registration number. Both should be recorded in
your boiler Log Book. You can check your installer is CORGI registered by calling CORGI direct on:- [phone].
Improper installation may cause damage or injury to individuals, animals and personal property for which the manufacturer will
not be held liable. To ensure efficient and safe operation it is recommended that the boiler is serviced annually by a competent
person.
If it is known that a fault exists on the appliance, it must not be used until the fault has been corrected by a competent person.
To The Installer
As part of the commissioning of this appliance it is vital that the Log Book is completed and given to the Householder. Please
ensure that your customer is aware of the importance of keeping the Log Book safe as a record of the installation and the
appliance service history.
Please ensure that your customer is aware of the correct operation of the system, boiler and controls.
MTS recommend the use of protective clothing, when installing and working on the appliance i.e. gloves.
This instruction booklet is especially designed for appliances installed in the UK and the Republic of Ireland
1. GENERAL INFORMATION

4
2. CONTROL PANEL
* Warning the flue analysis mode must only be selected by a qualified service engineer.
ON/OFF RESET
COMFORT
1
1
2
2
3
3
4
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5
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7
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8
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9
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12
12
I
36
37
30
26
32
29
33
34
Control panel (Fig. 2.1)
26. - On/off push button
27. - Reset push button
28. - domestic hot water function and COM-
FORT tank on/off button
29. - burner operation green indicator light
30. - red indicator lock-out light
31. - yellow indicator - Comfort button
32. - Central Heating control knob
stop/mini/maxi
33. - DHW control knob /mini/maxi
34. - Increasing button +
35. - Reducing button -
36. - Menu button
37. - Pressure gauge
46. - Time clock
48. - Display
35
27
28
31
48
46
FIG. 2.1
USER INSTRUCTIONS
Connecting bracket
Taps shown in Open position (Fig. 2.2)
39 : Gas service tap
40 : Water service tap
41 : Central heating flow isolating valve
42 : Central heating return isolating valve
43 & 44: Filling taps
45 : Filling loop
Fig. 2.2
41
42
43 44
45
39
40

5
3. HOW TO USE Switching on
1. Check that the pressure in heating system is
adequate, i.e. the pressure gauge 37 shows 1
bar minimum and 1.5 bar maximum.
2. Check that the gas service tap 39 (Fig. 3.1) is
opened (Figs. 3.2 and 3.3) and that the mains
power is on, On/Off push button 26 Power
ON.
The boiler is now ready to use.
Note : If the boiler has been turned off for some
time, the presence of air in the gas pipe
may result in a lockout.
+
+
FIG. 3.2 FIG. 3.3
GAS COCK CLOSED GAS COCK OPEN
FIG. 3.1
COMFORT
ON/OFF RESET
COMFORT
26 27
30
32
32
32
39
Ignition procedure
Press the button 26, the electronic control unit will ignite the
burner without any manual intervention (only when there is a
demand for Domestic hot water or heating). If the burner does not
ignite within the safety period, the screen will display error code A01
and the warning light 30 will come on.
To reinitialise the ignition system, press the button 27.
If ignition fails again, verify that the gas tap is open before calling a
qualified technician.
RESET
ON/OFF
Summer and winter operation
The boiler produces hot water for heating and Domestic hot water.
Winter operation means the production of hot water for heating and
the production of Domestic hot water. Summer operation means the
production of Domestic hot water only. The boiler control panel
allows selection of winter or summer operation.
Keep the knob 32 in the position to select summer operation. To
select winter operation, turn the knob 32 to a position between the
minimum value and the maximum value.
Heating temperature control
To adjust the heating water temperature, use the knob 32, position
the pointer between the minimum and maximum values; the
temperature obtained can vary between 42°C and 82°C or 25°C and
75°C.
The heating command is activated by a mechanical programmer, or
the room thermostat or a remote unit.
Installation with regulation by external temperature
(Only activated if the external sensor is installed)
In this case, by turning the knob 32, it is possible to change the heating outlet temperature and
therefore the ambient temperature of your home. When the knob is turned, the display indicates
P6 and the heating outlet temperature can be varied by - 20 °C to 20 °C.
However, the boiler can be controlled by the timeswitch, a Clima Manager remote control or a
room thermostat.
As soon as the desired temperature is reached, the burner is switched off and the circulation
pump stops or goes into post-circulation mode.
32

6
The boiler is fitted with a device, which in the event that the water
temperature falls below 8oC the pump activates and runs until a
temperature of 18oC is attained. In the event that the water
temperature falls below 3oC, the diverter valve switches to Domestic
Hot Water and the burner fires on minimum power until a temperature
of 33oC is attained.s
This device is only activated when the boiler is operating perfectly and
- the system pressure is sufficient;
- the boiler is powered electrically;
- gas is available.
Schedule an annual maintenance check-up for the boiler with a CORGI
registered Service Engineeer in the UK and with a competent person
as described in I.S.813 for IE.
Correct maintenance always results in savings in the cost of running
the system.
4. ANTI-FROST DEVICE
5. MAINTENANCE
COMFORT
ON/OFF
33
32
R
COMFORT
Afficheur gauche Afficheur droit
28
Regulation of Domestic hot water
To obtain Domestic hot water, press the button COMFORT 28
(yellow LED comes on)
To adjust the Domestic hot water temperature in winter or summer
operation, use the knob 33. It is possible to determine the temperature of
water stored in the tank between 40°C and 70°C.
COMFORT
Interruption of heating
To interrupt heating, turn the knob 32 to the sun position .
The boiler will continue to operate in the summer position to provide
Domestic hot water only.
Switch-off procedure
To switch the boiler off, press the button 26. Close the gas tap
located under the boiler and move the boiler external power supply switch
to the OFF position.
ON/OFF
Display: display of current operations
During operation of the boiler, in other words when it is performing its
normal functions, the left side of the display shows a series of characters
referring to the operations, as indicated below:
0 No heating command
C Heating
c pump in post-circulation mode for heating
d Domestic hot water
h Pump in post-circulation mode for Domestic hot water
b Tank reheating
On the right, the display shows (2 characters):
- in heating mode: heating installation output temperature
- in Domestic hot water distribution mode: drawing-off temperature.
- in tank reheating mode: tank temperature or drawing-off temperature.

7
COMFORT
AFFICHEUR CAUSE
A01 Three ignition attempts
A03 The output temperature exceeds 105°C during operation
A07 Too many flame separations over a period during operation
A17 Input water circulation fault
A18 No water circulation
A33 Fan problem
A97 Electronic control problem
A98 Electronic control problem
A99 Electronic control problem
6. TROUBLE SHOOTING
7. FILLING INSTRUCTIONS A method for initially filling the system and replacing lost water
during servicing and initial filling (in accordance with current Water
Regulations), is provided as an integral part of the connection kit
(see Fig. 3.1).
To fill the system and replace lost water it is necessary to proceed
as follows:
- Switch off the power to the boiler;
- Ensure that the flexible hose is connected to both the cold
water inlet connection and the C.H. flow connection;
- Open the black lever on the valve for the C.H. flow connection
and slowly open the black handle on the valve for the cold water
inlet until water is heard passing through the valves;
- Once the pressure gauge 37 (Fig. 2.1) reads between 1 and
1.5 bar close the levers on both the cold water connection and the
C.H. flow connection
- Switch the power to the boiler back on.
NOTE: THE FLEXIBLE HOSE MUST BE REMOVED ONCE THE SYSTEM HAS
BEEN FILLED.
FIG. 7.1
CONDITIONS FOR STOPPAGE OF THE BOILER
This boiler is fitted with safety devices which are activated in certain situations
and cause the boiler to stop operating.
There are two types of stoppage:
- Operating failure (A)
- Safety stop (E)
OPERATING STOPPAGE "A"
This type of stoppage is displayed in the form of a number preceded by a
letter (A) as shown in the following table.
To clear this type of stoppage, press the reset button (Reset).
In the table, each error code is associated with the problem causing it to
appear.
In the case of error
A 02 , before
calling a qualified technician, check
the pressure gauge to see if the
water pressure in the appliance is 1
bar. If necessary, restore the
pressure using the filling valve
located under the boiler and perform
an ON/OFF operation by pressing
the button. If the pressure falls
frequently in the appliance, have a
plumber check for water leaks.
N.B. Warning! The boiler is always
connected to an electrical supply.
IMPORTANT
If this type of failure occurs too often,
call an approved after sales technical
service. For safety reasons, the
boiler will only allow 5 reignition
attempts in 15 minutes (pressing of
the RESET button). After the fifth
attempt, the boiler goes into safety
shutdown mode E 99.
This is therefore not a problem in the
case of sporadic or isolated
stoppages.
SAFETY SHUTDOWN “E”
In the event of a safety shutdown, indicated by display of the letter E followed by a
number, there is no need to take action. The boiler will automatically attempt to reset and
restart. If this does not occur, call a qualified technician. Switch off the boiler as described
in the previous paragraph, close the gas tap and move the external electrical supply
switch to the OFF position.
Antilocking of pump and three-way valve
To prevent locking of the components, the appliance performs a self-test every 24 hours:
the pump starts up for 3 seconds and the diverting valve is operated.

8
8. TIME CLOCK
1. General layout
The mechanical clock covers a 24 hour period. Each tappet
represents 15 minutes A (Fig 8.1). An override switch is located on
the clock B (Fig 8.1).
2. To set the time
To set the time of day, grasp the outer edge of the dial and turn
slowly clockwise until the correct time is lined up with the arrow C
(Fig. 8.1).
3. To Set the "On" and "Off" times
The clock uses a 24hours system. e.g. 8 = 8.00 am and
18 = 6.00 pm "ON" periods are set by sliding all tappets between
the "ON" time and the "OFF" time to the outer edge of the dial.The
tappets remaining at the centre of the dial are the "OFF" periods.
4. For operation
Put the selector switch Bto the symbol to control the central
heating by the clock. Put the switch Bto «I» to select permanent
operation or to «0» to turn the central heating off permanently.
1
1
2
2
3
3
4
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5
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6
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7
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9
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6
6
12
12
I
A
C
B
8.1 Setting the Mechanical Clock
FIG. 8.1

9
P
r
o
g
.
h
m
Day
Manual switch
Summer and
winter time
setting
Reset
Enter
weekday/s
Enter
the hours
Week-
days
flash
Enter
minutes
Enter
switching
times
Imput
time
Automatic Manual Continuous
Operation Operation Operation
The switching If the current You can only
times corres- switching mode is return to automatic
pond to the changed manually, mode from the
program the next switching continuously-ON
entered. time will be and continuously-
 carried out auto- OFF switching
 matically again modes by
 according to the pressing the " "
 entered switching key.
 program.
= ON = ON = Continuously ON
= OFF = OFF = Continuously OFF
Operating the time switch
The step marked with the symbol “ ” are necessary to carry out a
switching program.
Preparing for Operation
Activate the “Res” switch (=RESET) to reset the time switch to its
default setting (activate using a pencil or similar pointed instrument).
Do this:
- every time you wish to “reset” the time switch
- to erase all switching times and the current time of day.
After approximately two seconds the following display appears:
Enter current time and weekday
- Keep the “ ” key pressed down
During the summer time period press the +/- 1h key once.
Enter the hour using the “h” key
Enter the minutes using the “m” key
Enter the day using the “Day” key
1 = “Monday”..............7 = Sunday
- Release the “ ” key.
Entering the switching times
You have 20 memory Iocations available. Each switching time takes
up one memory location.
Keep pressing the “Prog” key until a free memory location is shown in
the display “– –:– –”.
8.2 Setting the Digital Clock

10
Programme ON or OFF with the “ ” key:
“ ”= OFF; “ ”= ON
Enter the hour using “h”
Enter the minutes using “m”
If a switching command is to be carried out every day (1 2 3 4 5 6
7) then store using the “ ” key, otherwise select the day(s) it is to
be carried out by using the “Day” key.
When the day seIection is left bIank, the programmed switching
instruction operates at the same time every day
1 2 3 4 5 6 = Monday – Saturday
1 2 3 4 5 = Monday – Friday
6 7 =Saturday – Sunday
Selection of single days: 1 = Mon. .............. 2 =Tues.
Save the switching time with the “ ” key.
The time switch enters the automatic operating mode and displays
the current time of day.
Begin any further entry of a switching time with the “Prog” switch. If
your entry is incomplete, the segments not yet selected will blink in
the display. After programming is completed, and you return the
time clock to the current time display with the “ ” key, the time
clock will not activate any switching instruction required for the
current time. You may need to manually select the desired
switching state with the “ ” key. Thereafter, as the unit
encounters further switching instructions in the memory in real time,
it will correctly activate all subsequent switching instructions.
Manual Override Switch “ ”
With the “ ” you can change the current setting at any time. The
switching program already entered is not altered.
Reading the programmed switching times
Pressing the “Prog” key displays the programmed switching times until
the first free memory location appears in the display “– – : – –”.
If you now press the “Prog” key once again, the number of free memory
Iocations will be displayed, e.g. “18”. If all memory locations are
occupied, the display “00” appears.
Changing the programmed switching times
Press the “Prog” key repeatedly until the switching time you want to
change is displayed. You can now enter the new data. See point
“Entering the switching times”.
Notes on storing switching times:
If you end your entry of the switching times by pressing the “Prog” key,
then the switching time you have entered will be stored and the next
memory location displayed.
In addition, a complete switching command is stored automatically
after around 90 seconds provided no other key is pressed. The time
switch then enters the automatic operating mode and displays the
current time again.
Deleting individual switching times
Press the “Prog” key repeatedly until the switching time you wish to
delete is shown in the display. Then set to “– –” using the “h” or “m” key
and keep the “ ” key pressed down for around 3 seconds. The
switching time is now erased and the current time is displayed.
AM / PM time display
If you press the “+/-1h” and “h” keys at the same time, the time display
switches into the AM/PM mode.

11
Read the instructions and recommendations in these Installation and Servicing Instructions carefully to ensure proper installation,
use and maintenance of the appliance.
Keep this manual in a safe place. You may need it for your own reference while Servicing Technicians or your installer may need
to consult it in the future.
This is a combined appliance for the production of central heating (C.H.) and domestic hot water (D.H.W.).
This appliance must be used only for the purpose for which it is designed.
The manufacturer declines all liability for damage caused by improper or negligent use.
No asbestos or other hazardous materials have been used in the fabrication of this product.
Before connecting the appliance, check that the information shown on the data plate and the Technical Information (Section 21)
comply with the electric, water and gas mains of the property. You will find the data plate on the reverse of the control panel.
Do not install this appliance in a damp environment or close to equipment which spray water or other liquids.
Do not place objects on the appliance.
Do not allow children or inexperienced persons to use the appliance without supervision.
If you smell gas in the room, do not turn on or off light switches, use the telephone or any other object which might cause
sparks.
Open doors and windows immediately to ventilate the room.
Shut the gas mains tap (at or adjacent to the gas meter) or the valve of the gas cylinder and call your Gas Supplier immediately.
If you are going away for a long period of time, remember to shut the mains gas tap or the gas cylinder valve.
Always disconnect the appliance either by unplugging it from the mains or turning off the mains switch before cleaning the
appliance or carrying out maintenance.
In the case of faults or failure, switch off the appliance and turn off the gas tap. Do not tamper with the appliance.
For repairs, call your local Authorised Servicing Agent and request the use of original spare parts. For in-guarantee repairs
contact MTS (GB) Limited.
Check the following at least once a year:
1 - Check the seal of water connections, replacing the gaskets if necessary.
2- Check the seal of the gas connections, replacing the gaskets if necessary.
3- Check the general condition of the appliance and of the combustion chamber visually.
4 - Visual check of the combustion: clean burners if necessary.
5- With reference to point 3, dismantle and clean the combustion chamber if necessary.
6 - With reference to point 4, dismantle and clean the injectors if necessary.
7- Visual check of the primary heat exchanger:
- check for overheating of the exchangers fins;
- clean the exhaust side of the exchanger and fan if necessary.
8- Regulate the gas pressure, ignition pressure, partial flame, maximum flame.
9- Check proper operation of the heating safety system:
- maximum safety temperature;
- maximum safety pressure.
10 - Check the proper operation of the gas safety system:
- gas or flame safety device;
- gas valve safety device.
11 - Check that the electrical connections have been made in compliance wit h the instructions shown in the Installation
Instructions.
12 - Check the efficiency of the hot water supply (flow and temperature).
13 - Check pressure in the Domestic Expansion Vessel and top up as necessary.
14 - Check manually by turning the test knob the Temperature & Pressure Relief Valve.
15 - Check manually by turning the test knob the Expansion Relief Valve.
16 - Check discharge pipes from both the central heating and domestic hot water for obstructions.
17 - Check general operation of the appliance.
18 - Check the exhaust system for the combustion products.
19 - Check all unvented domestic hot water controls and systems
NOTE: These checks are not exhaustive
9. GENERAL INFORMATION FOR THE INSTALLER
INSTALLER INSTRUCTIONS

12
9.1 OVERALL VIEW
1
2
3
4
5
6
8
10
11
13
14
7
15
16
18
12
19
17
9
21
20
22
23
24
25
FIG. 9.1
1. - sheet steel casing
2. - pressurised expansion tank
3.- sealed casing
4. - burner/exchanger assembly
5. - 24 V fan
6. - air/gas connection assembly
7. - ignition electrodes
8. - flame detection electrode
9. - stainless steel Domestic hot water tank
10. - circulation pump
11.- electronic control unit
12. - ignition transformer
13.- overheat cut-off
14. - gas valve
15. - tank sensor
16. - heating outlet sensor
17. - heating return sensor
18.- distributor valve
19. - stainless steel plate Domestic hot water
exchanger
20. - Domestic hot water flow rate controller
21. - Domestic hot water sensor
22. - silencer
23. - siphon
24. - Domestic hot water expansion cylinder
25. - pressure switch

13
The technical information and instructions provided herein below are
intended for the installer / Servicing Technician so that the unit may be
installed and serviced correctly and safely.
There will be two items:
1 - The fully assembled boiler
2 - A separately boxed connection kit
WATER REGULATIONS
In GB it is necessary to comply with the Water Supply (Water Fittings)
Regulations 1999, for Scotland, The Water Bylaws 2000, Scotland. The
Genus 30 Plus is an approved product under the Water Regulations.
To comply with the Water Regulations, you attention is drawn to The Water
Regulations guide published by the Water Regulations Advisory Scheme
(WRAS) gives full details of the requirements.
In IE, the requirements given in the current edition of I.S.813 and the
current Building Regulations must be followed.
BUILDING REGULATIONS
These are a statutory document and take priority over all other regulations
and recommendations. The installation of an unvented hot water storage
cylinder is classified as a "Controlled Service" and Regulation G3 applies.
To meet the requirements of the Regulation, installation of an unvented
system should be undertaken by a "competent installer".
All installations of unvented hot water storage systems having a capacity of
more than 15 litres should be notified to the relevant Local Authority by
means of Building Notice or by the submission of full plans. It is important
to note that it is a criminal offence to install an unvented hot water storage
system without notifying the Local Authority.
The installation of this appliance must be in accordance with the
relevant requirements of the Local Building Regulations, the current
I.E.E. Wiring Regulations, the bylaws of the local water authority, in
Scotland, in accordance with the Building Standards (Scotland)
Regulation and Health and Safety document No. 635 “Electricity at work
regulations 1989” and in the Republic of Ireland with the current edition
of I.S. 813, the Local Building Regulations (IE).
C.O.S.H.H.
Materials used in the manufacture of this appliance are non-hazardous
and no special precautions are required when servicing.
Installation should also comply with the following British Standard
Codes of Practice:
10. INSTALLATION
10.2 Reference Standards
10.1 Delivery
BS 7593 Treatment of water in domestic hot water
central heating systems
BS 5546 Installation of hot water supplies for
domestic purposes
BS 5440-1 Flues
BS 5440-2 Air supply
BS 5449 Forced circulation hot water systems
BS 6798 Installation of gas fired hot water boilers
of rated input not exceeding 60kW
BS 6891 Installation of low pressure gas pipe up to
28mm
BS 7671 IEE wiring regulations
BS 7074 Specification for expansion vessels
BS 5482 Installation of L.P.G.

10.3 Siting the Appliance
14
and in the Republic of Ireland in accordance with the following
Codes of Practice:
WARNING!!
The addition of anything that may interfere with the normal
operation of the appliance without express written permission of
the manufacturer or his agent could invalidate the warranty. In GB
this could also infringe the GAS SAFETY(Installation and Use)
REGULATIONS.
In the Republic of Ireland the installation and initial start up of the
appliance must be carried out by a Competent Person in
accordance with the current edition of I.S.813 “Domestic Gas
Installations”, the current Building Regulations, reference should
also be made to the current ETCI rules for electrical installation.
The appliance may be installed in any room or indoor area,
although particular attention is drawn to the requirements of the
current I.E.E. Wiring Regulations, in Scotland, the electrical
provisions of the Building Regulations applicable in Scotland, and
in the Republic of Ireland, the current edition of I.S.813, with
respect to the installation of the combined appliance in a room
containing a bath or shower. The location of the boiler in a room
containing a bath or shower should only be considered if there is
no alternative.
Where a room-sealed appliance is installed in a room
containing a bath or shower reference should be made to the
relevant requirements.
In GB this is the current I..E.E. WIRING REGULATIONS and
BUILDING REGULATIONS. In IE reference should be made to
the current edition of I.S.813 and the current ETCI rules.
If the boiler is to be sited into a timber framed building, reference
must be made to the current edition of the Institution of Gas
Engineers Publication IGE/UP/7 (Gas Installations in Timber
Framed Housing).
The location must permit adequate space for servicing and air
circulation around the appliance as indicated in Section 10.4.
The location must permit the provision of an adequate flue and
termination.
For unusual locations special procedures may be necessary.
BS 6798-1987 gives detailed guidance on this aspect.
A compartment used to enclose the appliance must be designed
specifically for this purpose. No specific ventilation requirements
are needed for the installation within a cupboard.
This appliance is not suitable for outdoor installation.
I.S. 813 Domestic Gas Installations
The following BS Standards give valuable information;
BS 5546 Installation of hot water supplies for
domestic purposes
BS 5449 Forced circulation hot water systems
BS 7074 Specification for expansion vessels
BS 7593 Treatment of water in domestic hot water
central heating systems

15
10.5 Overall Dimensions
925
500
950
470
195
57
54 145
39
40
41
42
43
38
188
135
80
54 172 54
317
280
44
595
450mm minimum for
servicing purposes
180
FIG. 10.1
The type C appliances (in which the combustion circuit,
air vent intake and combustion chamber are air-tight
with respect to the room in which the appliance is
installed) can be installed in any type of room.
Secondary ventilation is not required with this boiler. The
boiler must be installed on a solid, non-combustible,
permanent wall to prevent access from the rear.
In order to allow for access to the interior of the boiler for
maintenance purposes, the boiler must be fitted with a
clearance of 450 mm in front 400 mm below the boiler and
200mm above the boiler, and installed in compliance with the
clearance requirements indicated in Fig. 10.1.
Legend:
39 = Gas service tap
40 = Heating return
41 = Heating flow
42 = Water service tap
43 = Tank hot water flow
38 = Water tank
discharge valve
44 = Central heating
discharge valve
10.4 Clearances

16
After removing the boiler from its packaging, remove the
template from the separate box containing the connection
kit. NOTE: Pay particular attention to any test water that
may spill from the appliance.
Place the template in the position the appliance is to be
mounted and after ensuring it is hanging squarely, use it to
drill the holes for the hanging bracket, connection kit and
flue pipe(s) NB: For further information relating to the flue
installation please refer to Section 11 FLUE CONNECTION. (If
the appliance is to be fitted on a wall of combustible
material, the wall must be protected by a sheet of fireproof
material).
If the appliance is to be fitted into a timber framed building,
guidance should be sought from the Institute of Gas
Engineers document REF: IGE/UP/7.
10.6.1. Drill the wall and plug using those supplied with
the connections kit, position the hanging bracket and
secure with the wall bolts supplied, assembl the
connection kit and secure to the wall. NOTE:It is highly
recommended that a spirit level be used to position the
appliance to ensure that it is perfectly level.
10.6.2. Position the appliance on the hanging bracket
and connect the connection kit to the boiler connections.
(see also Sections 10.8 Gas Connections, 10.9 Water
Connections & FIG.10.2).
For safety purposes, have a competent person carefully
check the electrical system in the property, as the
manufacturer will not be held liable for damage caused by
the failure to earth the appliance properly or by anomalies
in the supply of power. Make sure that the residential
electrical system is adequate for the maximum power
absorbed by the unit, which is indicated on the rating plate.
In addition, check that the section of cabling is appropriate
for the power absorbed by the boiler.
The boiler operates with alternating current, as indicated in
the Technical Information table (Section 21), where the
maximum absorbed power is also indicated. Make sure
that the connections for the neutral and live wires
correspond to the indications in the diagram. The
appliance electrical connections are situated on the
reverse of the control panel (see the Servicing Instructions
Section 18 for further information).
Important!
In the event that the power supply cord must be changed,
replace it with one with the same specifications. Make the
connections to the terminal board located within the control
panel, as follows:
- The yellow-green wire should be connected to the
terminal marked with the earth symbol; make sure to re-
use the ferrule mounted on the other supply cord;
- The blue wire should be connected to the terminal
marked “N”;
- The brown wire should be connected to the terminal
marked “L”.
Note: The diagrams for the electrical system are indicated
in Section 13.
FIG. 10.3
10.7 Electrical Connection
10.6 Mounting the Appliance
Legend:
39 = Gas service tap
40 = Heating return
41 = Heating flow
42 = Water service tap
43 = Tank hot water flow
38 = Water tank valve
44 = Heating valve
FIG. 10.2
39
40
41
38
44
42 43

17
10.8 Gas Connection
Warning, this appliance must be earthed.
External wiring must be correctly earthed, polarised and in
accordance with relevant regulations / rules. In GB this is the
current I.E.E. WIRING REGULATIONS. In IE reference should be
made to the current edition of the ETCI rules. This boiler is supplied
for connection to a 220 - 240 V~ 50 Hz supply.
The supply must be fused at 3 A.
The method of connection to the electricity supply must facilitate
complete electrical isolation of the appliance, by the use of a fused
double pole isolator having a contact separation of at least 3 mm in
all poles or alternatively, by means of a 3 A fused three pin plug
and unswitched shuttered socket outlet both complying with BS
1363.
The point of connection to the Electricity supply must be readily
accessible and adjacent to the appliance unless the appliance is
installed in a bathroom when this must be sited outside the
bathroom.
The local gas region contractor connects the gas meter to the
service pipe.
The gas installation should be in accordance with the relevant
standards. In GB this is BS6891 and in IE this is the current edition
of I.S.813.
The connection the the appliance is a 22 mm copper tail located at
the rear of the gas service cock (Fig. 10.2).
If the gas supply for the boiler serves other appliances ensure that
an adequate supply is available both to the boiler and the other
appliances when they are in use at the same time.
Pipe work must be of an adequate size. Pipes of a smaller size than
the boiler inlet connection should not be used.
Central Heating
Detailed recommendations are given in BS 6798:1987 and BS
5449-1:1990, the following notes are given for general
guidance.
Pipe Work:
Copper tubing to BS EN 1057:1996 is recommended for water
pipes. Jointing should be either with capillary soldered or
compression fittings.
Where possible pipes should have a gradient to ensure air is
carried naturally to air release points and water flows naturally
to drain taps.
The appliance has a built-in automatic air release valve,
however it should be ensured as far as possible that the
appliance heat exchanger is not a natural collecting point for air.
Except where providing useful heat, pipes should be insulated
to prevent heat loss and avoid freezing.
Particular attention should be paid to pipes passing through
ventilated spaces in roofs and under floors.
By-pass:
The appliance includes an automatic by-pass valve, which
protects the main heat exchanger in case of reduced or
interrupted water circulation through the heating system, due to
the closing of thermostatic valves or cock-type valves within the
system.
10.9 Water Connections

18
System Design:
This boiler is suitable only for sealed systems.
Drain Cocks:
These must be located in accessible positions to permit the
draining of the whole system. The taps must be at least 15 mm
nominal size an manufactured in accordance with BS 2870:1980.
Safety Valve Discharge (Primary Water):
The discharge should terminate facing downwards on the exterior
of the building in a position where discharging (possibly boiling
water & steam) will not create danger or nuisance, but in an easily
visible position, and not cause damage to electrical components
and wiring.
The discharge must not be over an entrance or a window or any
other type of public access.
Mains Water Feed - Central Heating:
There must be no direct connection to the mains water supply
even through a non-return valve, without the approval of the Local
Water Authority, and must be in accordance with water supply
regulations. Your attention is drawn to, for GB: Guidance G24.2
and recommendation R24.2 of the water regulations guide and for
IE: the current edition of I.S.813.
Filling:
A temporary method for initially filling the system and replacing
lost water during servicing and initial filling (complying to current
water regulations and byelaws) is provided. The flexible hose
must be removed once the system has been filled.
Domestic Hot Water
Storage Discharge Pipe Work
1) The tundish must be installed directly below the discharge outlet
connection of the boiler. The tundish must also be in a position visible
to the occupants, and positioned away from any electrical devices.
The discharge pipe from the tundish should terminate outside in a
safe place where there is no risk to persons in the vicinity of the
discharge and to be of metal.
2) Discharge pipes from the temperature & pressure relief and
expansion relief valve are joined together within the appliance.
3) The pipe diameter must be at least one pipe size larger than the
nominal outlet size of the safety device unless it's total equivalent
hydraulic resistance exceeds that of a straight pipe 9m long.
i.e. Discharge pipes between 9m and 18m equivalent resistance
length should be at least 2 sizes larger than the nominal outlet size of
the safety device. Between 18 m and 27 m at least 3 sizes larger, and
so on.
Bends must be taken into account in calculating the flow resistance.
See fig. 10.4 (page 19) and Table 1 (page 20).
4) The discharge pipe must have a vertical section of pipe at least 300 m
in length, below the tundish before any elbows or bends in the
pipework.
5) The discharge pipe must be installed with a continuous fall.
6) The discharge must be visible at both the tundish and the final point of
discharge, but where this is not possible or practically difficult; there
should be clear visibility at one or other of these locations. Examples
of acceptance are:
i) Ideally below a fixed grating and above the water seal in a trapped
gully.
ii) Downward discharges at a low level; i.e. up to 100 mm above
external surfaces such as car parks, hard standings, grassed areas etc.
These are acceptable providing that where children may play or
otherwise come into contact with discharges, a wire cage or similar
guard is positioned to prevent contact, whilst maintaining visibility.

19
iii) Discharges at high level; I.e. into a metal hopper and metal down
pipe with the end of the discharge pipe clearly visible (tundish visible or
not).
Or onto a roof capable of withstanding high temperature discharges of
water 3 m from any plastic guttering systems that would take such a
discharge (tundish visible).
iv) Where a single pipe serves a number of discharges, such as in
blocks of flats, the number served should be limited to not more than 6
systems so that any installation can be traced reasonably easily.
500 mm Max.
300 mm
Min.
Temperature & pressure
relief valve Metal discharge pipe (D1) from
temperature & pressure relief valve.
to tundish.
Metal discharge pipe (D2) from tundish
with continuous fall. See Table 2 and worked
example.
Tundish
Fixed grating
Trapped gulley
Discharge below
fixed grating.
(see page 6 for
alternative points

of discharge).
Fig.10.4
The single common discharge pipe should be at least one pipe size large
than the largest individual discharge pipe to be connected.
If unvented hot water storage systems are installed where discharges
from safety devices may not be apparent I.e. in dwellings occupied by
the blind, infirm or disabled people, consideration should be given to
the installation of an electronically operated device to warn when
discharge takes place.
Note: The discharge will consist of scalding water and steam. Asphalt,
roofing felt and non-metallic rainwater goods may be damaged by such
discharges.
Warning
The outlet from the temperature & pressure relief valve must not be
used for any other purpose.
The temperature & pressure relief valve must not be removed in any
circumstances. Any of the above will totally invalidate the warranty.
Note
The discharge from the central heating and domestic hot water systems
may be joined together after the tundish.
Air Release Points:
These must be fitted at all high points where air naturally collects
and must be sited to facilitate complete filling of the system.
The appliance has an integral sealed expansion vessel to
accommodate the increase of water value when the system is
heated.

20
It can accept up to 7l (1.5 gal) of expansion water. If the heating circuit
has an unusually high water content, calculate the total expansion and
add an additional sealed expansion vessel with adequate capacity.
Domestic Water:
The domestic water must be in accordance with the relevant
recommendation of BS 5546:1990. Copper tubing to BS EN
1057:1996 is recommended for water carrying pipe work and must be
used for pipe work carrying drinking water. The domestic hot water
temperature should be be adjusted to trip at 60˚C. This temperature
will prevent the formation of limescale in hard water areas.
Note: This appliance is capable of producing domestic hot water of
up to 70˚C. For extra security against scalding a thermostatic
blending valve may be installed on the domestic hot water
outlet.
Secondary Return :
The secondary return connection can be used as an option. A Non
Return Valve (not supplied) must be fitted to prevent back flow and a
Bronze Pump will be needed in conjunction with a Pipe Thermostat to
circulate the hot water (neither of which are supplied).
Valve outlet size Minimum size of
discharge pipe D1*
Minimum size of
discharge pipe D2*
from tundish
Maximum
resistance allowed,
expressed as a
length of pipe (i.e.
no elbow or bends)
Resistance created
by each elbow or
bend
G 1/2 15 mm 22 mm
28 mm
35 mm
Up to 9 m
Up to 18 m
Up to 27 m
0.8 m
1.0 m
1.4 m
G 3/4 22 mm 28 mm
35 mm
42 mm
Up to 9 m
Up to 18 m
Up to 27 m
1.0 m
1.4 m
1.7 m
G 1 28 mm 35 mm
42 mm
54 mm
Up to 9 m
Up to 18 m
Up to 27 m
1.4 m
1.7 m
2.3 m
Worked Example:
The example below is for a G 1/2 Temperature & Pressure Relief valve
with a discharge pipe (D2) having 4 no. elbows and length of 7 m from the
Tundish to the point of discharge.From Table 1
Maximum resistance allowed for a straight length of 22 mm copper
discharge pipe (D2) from G 1/2 T & P valve is 9m.
Subtract the resistance for 4 no. 22 mm elbows at 0.8m each = 3.2 m.
Therefore the maximum permitted length equates to: 5.8 m.
As 5.8m is less than the actual length of 7 m therefore calculate the next
largest size.
Maximum resistance allowed for a straight length of 28 mm pipe (D2) from
G 1/2 T & P valve equates to: 18 m.
Subtract the resistance for 4 no. 28 mm elbow at 1.0m each = 4 m.
Therefore the maximum permitted length equates to: 14 m
As the actual length is 7 m, a 28 mm (D2) copper pipe will be satisfactory.
Table 1. Sizing of copper discharge pipe “D2” for
common temperature valve outlet sizes.