Heatline Vizo 24 User guide

vizo 24/28
24/28
Installation,Servicing
&UserInstructions
Condensing wall
mounted Combination
Boiler

vizo 24/28
Natural Gas / LPG
HEATLINE™ Vizo24 / Vizo28 Condensing Combination Boilers
British Gas Service Listing
Vizo 24 Condensing Combination Boiler G.C.No 47-157-08
Vizo 28 Condensing Combination Boiler G.C.No 47-157-09
Type test for purpose of Regulation 5 certified by:
Notified Body IMQ
51BP2727 CE Directives 90/396/EEC
51BP2728DR CE Directives 92/42/EEC
Product/Production certified by:
Notified Body IMQ
51BP2727 CE Directives 90/396/EEC
51BP2728DR CE Directives 92/42/EEC
The manufacturer, in the continuous process to improve his products, reserves the right to modify the data expressed in
the present documentation at any time and without prior notice.
The present documentation is an informative support and it cannot be considered as a contract towards third parties.
The HEATLINE™ range of heating boilers is manufactured from high quality materials, enabling reliability and
optimum performance.
HEATLINE™ is committed to the continual development of their appliances to ensure their customers benefit from the
latest advances in combustion technology and energy savings.
'Benchmark' Log Book
As part of the industry-wide initiative the Vizo24/Vizo28 boilers come
complete with an Installation, Commissioning and Service Record Log
Book. Please read the Log book carefully and in accordance with current
regulations complete all sections relevant to the appliance and
installation. The details within the Log Book will be required in the event
of any warranty work.
On completion, the Log Book must be left with the end user and the
relevant sections completed on each subsequent Service visit.

vizo 24/28
Section Page
Preface 3
1. Installation Regulations 3
The Signs on Box 4
The Signs on Boiler 4
2. Technical Data 5
3. Boiler Characteristics 7
4. Operation 8
5. General Installation 9
6. Appliance Siting 11
7. Flue Terminal Location 11
8. General Flue Info 13
9. Electrical Connections 14
10. Boiler Installation 16
11. Gas Supply 19
12. Filling the System 19
13. Control Panel Functions 19
14. Commissioning 20
15. Onboard Adjustments 21
16. Safety Devices 22
17. Routine Servicing 23
18. Component Replacement 25
19. Gas Type Conversion 32
20. Fault Finding Chart 33
Appendix
Spare Parts List 37
User Instructions 38
Contents

vizo 24/28
The Heatline™ gas fired, condensing combination boiler
meets the requirements of regulations and is deemed to meet
the requirements of:
 Gas Appliance Directive 90/396/EEC
 Efficiency Directive 92/42/EEC
 Low Voltage Directive 73/23 EEC (modified from 93/68)
 Electromagnetic Compatibility Directive 89/396 EEC
(modified from 93/68)
Heatline™ declares that the materials used in the
manufacturer of this appliance are non-hazardous and that no
substances harmful to health are contained within the
appliance.
The Vizo24 / Vizo28 must be installed in accordance with
these instructions and the regulations currently in force.
Read these instructions fully before installing or using the
appliance.
Heatline™ accepts no responsibility for unsatisfactory
performance of the appliance or flue arising from the failure
to comply with the installation instructions.
If the boiler is sold or installed to another customer, all
documents must be transferred from existing customer to the
new one.
Heat Line™ accepts no responsibility for the unsatisfactory
performance of the appliance or flue arising from the failure
to comply with the installation and user instructions.
Incorrect installation could invalidate your guarantee and
may lead to prosecution.
If the appliance is re-sold or installation transferred the
appliance must be re-registered with Heatline in order to
maintain the guarantee.
The boiler must be installed in accordance with these
instructions and the regulations currently in force. Read
these instructions carefully before installing or using the
appliance.
1.1. This appliance must be installed in accordance with
the Rules in Force by a registered C.O.R.G.I.
engineer in accordance with the Gas Safety
(Installation and Use) Regulations. Failure to install
this appliance correctly may invalidate your
guarantee and may lead to prosecution.
1.2. Your C.O.R.G.I. registered engineer should carry a
C.O.R.G.I. ID card containing their registration
number, which should be recorded in your
BENCHMARK Log Book, which is supplied with
the Instructions. You can check the validity of this
ID number by contacting C.O.R.G.I. on 0870 401
2300.
1.3. This appliance must be installed in accordance with
the Gas Safety (Installation and Use) Regulations,
current Building Regulations, Building Standards
(Scotland), I.S.813 Installation of Gas Appliances
(Ireland), IEE Wiring Regulations (BS 7671), Health
and Safety Document No. 635 (Electricity at Work
Regulations) and Local Water Authority Bye Laws.
1.4. On installation the following British Standards must
also be considered:
oBS 6798 Specification for installation of gas fired
hot water boilers of rated input not exceeding
70kW.
oBS 5449 Central heating for Domestic Premises.
oBS 5546 Installation of gas hot water supplies for
domestic purposes.
oBS 5440 Flues and Ventilation for gas appliances
of rated input not exceeding 70kW (Part 1 Flues)
oBS 5440 Flues and Ventilation for gas appliances
of rated input not exceeding 70kW (Part 2 Air
Supply)
oBS 6891 Installation of low pressure gas pipe-
work installations up to 28mm (RI).
1.5. Due to the manufacturer’s continuous improvement
policy the manufacturer reserves the right to change
any specification of the appliance or make
modifications to these instructions, which meet
current regulations at the time of print. However, the
instructions must not be taken as overriding statutory
requirements.
1.6. To ensure reliability and continued performance
ensure that other components in the system are also
approved to relevant standards and that the appliance
and system is adequately protected and maintained on
an annual basis.
For further information or advice contact Heatline
TM
Service & Technical Enquiries in UK on 0870 777 8318,
Ireland on 01 466 4664 or E–mail via our web site
www.heatline.co.uk.
Preface
Warnings
1. Installation Regulations
03

vizo 24/28
The sign of approval the Vizo24 & Vizo28
Boilers have been certified by GASTEC
Italy.
This is a fragile piece of equipment: Do
not drop.
Avoid getting the box damp or wet.
The packed appliances may be stacked five
high.
Do not crush the packaging as this may
damage the appliance.
.
Store the appliance upright as indicated on
the box.
Handling This appliance is heavy, truck if possible
and obtain assistance if required.
To remove the appliance:
1. Carefully slit or remove the sealing tape
being careful not to scratch the appliance
door.
2. Fully open the carton lid and remove any
instructions and componenets.
3. Read the instructions carefully before
installation of the appliance.
4. Roll the carton onto its open face.
5. Lift the carton free of the inner packaging.
6. Remove the mounting bracket and valve
package.
7. Stand the boiler on its base within the
styrene block and remove the top
packaging piece.
8. If you wish to remove the styrene base lie
the appliance on its back to do so.
This picture shows the terminal block,
which is located at the bottom left hand
side of the control panel cover, to which a
voltage free room thermostat may be
fitted. NOTE: This is a voltage free
connection and no power must be applied
to these terminals. For mains powered thermostat
connection, see section 9.5.
Warning! High Voltage: This sign is
located on the back of the control box
housing warning of high voltages within
the control box. Turn off and isolate the
appliance before removing this cover.
NOTE: Take care as there may be residual voltage
within some components
Potentiometer Cover: Removal of the
cover, which is found on the back of the
control box, gives access to the
adjustment potentiometers. NOTE: Do
not make any adjustments without
reading the instructions carefully.
The Signs on Box
The Signs on Boiler
04

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VIZO 24
(24 kW)
VIZO 28
(28 kW)
VIZO 24
(24 kW)
VIZO 28
(28 kW)
Heat Input (max)
kW
25,7 28,5 Maximum heating temperature
ºC
85
85
Heat Output (max)
kW
24,82 27,47 Max. domestic hot water
temperature
ºC
64 64
Heat Input (min)
kW
10,12 15 Operating pressure (Bar)
PMS
Nominal
(Min)
3
1.5
(0,8)
3
1.5
(0,8)
Heat Output (min)
kW
9,27 14,26 Domestic water supply
pressure (Bar)
PMS
(Min)
8
(0,25)
8
(0,25)
Useful
efficiency at 100%
load
%
96,6 96,4 Expansion Vessel Capacity
Litres
7 7
Useful efficiency at 30% load
%
99.09 101 Expansion Vessel
Pre-charge Pressure
bar
0,5 0,5
Burner injector
mm.
1,23 NG
0.76 LPG
1,20 NG
0.76 LPG
Domestic Water Supply
Output at 35º C ∆T
L/min
9,92 11,3
Burner Pressure
(Natural Gas)
mbar Max
12.7
Mi n 2.0
Max 11,6
Mi n 3,5
Air Intake Pipe Diameter
mm
100 100
Burner Pressure (Propane)
mbar
Max 27,9
Min 4,4
Max 27,7
Min 6,1 Flue Pipe Diameter
mm
60 60
Power Supply
Input
220-240V-50Hz Max. Flue Length (Horizontal)
m
2.5 60/100
7.0 80/125
2.5 60/100
7.0 80/125
Max. power consumption Watt 164 Max. Flue Length (Vertical)
m
3.0 60/100
8.0 80/125
3.0 60/100
8.0 80/125
Level of Protection IPX 4 D Equivalent Length 45
0
Bend
Equivalent Length 90
0
Bend
m
1.0
1.5
1.0
1.5
Case Dimensions 24kW
mm
330d x 405w x 720h Net weight
Kg
37 38
Case Dimensions 28kW
mm
330d x 430w x 720h Gross Weight
kg
40 41
2. Technical Data
05

vizo 24/28
Key
1 - Fan
2 - Air Pressure Switch
3 - Fan Hood
4 - Primary Heat Exchanger
5 - Combustion Chamber
6 - Ignition Electrode
7 - Flame Sensor Electrode
8 - Burner
9 - Overheat Safety Thermostat
10 - Heating Sensor
11 - Automatic Air Vent
12 - Pump
13 - Water Pressure Switch/Sensor
14 - D.H.W. Flow Sensor
15 – Heating Circuit– Pressure Safety Valve
16 - Gas Valve
17 - Secondary Heat Exchanger
18 - Three-Port Valve Motor
19 - D.H.W. Sensor
20 - Three-Port Valve
21 - Filter Valve ( Below the pump)
22 - Expansion Vessel (At rear of the boiler)
23 - Condensing Unit
A - Heating Flow (22mm)
B - D.H.W. Outlet (15mm)
C - Gas Inlet (22mm)
D - Cold Water Inlet (15mm)
E - Heating Return (22mm)
A B C D E
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 21
22
23
At Rear Side
At Rear Side
06

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3.1 The Vizo24 / Vizo28 is a fan flued, wall-mounted
condensing type combination boiler that supplies both
central heating and mains fed domestic hot water.
Being room sealed the boiler may be installed in any
room or internal compartment without the need for
purpose made ventilation. However, if the boiler is
installed in a compartment it is recommended that the
compartment is ventilated for cooling purposes. A
functional diagram of the boiler’s principal
components is given as figure 1.
3.2 Range rated from 24kW to 28kW the Vizo24 /
Vizo28 heat output can be focused to match the
designed heating systems requirements by a simple
adjustment.
3.3 An electronic control unit, consisting of a PCB,
which includes ignition module provides direct burner
ignition and flame supervision along with continuous
modulation of the burner’s gas supply.
3.4 An interface unit, which includes boiler
adjustment potentiometers and fault display provides
easy service ability to the boiler.
3.5 Heat transfer to the boiler’s primary hydraulic
circuit is obtained via a primary, gas to water heat
exchanger contained within a hermetically sealed
combustion chamber. A 230 volt, single speed fan
expels the products of combustion from the
combustion chamber to outside air via an associated
flue system. The fan is activated at the beginning of
each ignition cycle and its operation monitored by
means of negative and positive sensing points
connected to an air pressure switch.
3.6 A secondary heat exchanger allows the
instantaneous transferral of heat from the primary
hydraulic circuit to water destined for domestic hot
water use. The secondary heat exchanger is sized so
as to minimise thermal shock and is protected against
the build up of lime scale by limiting the D.H.W.
outlet water temperature to a maximum of 64°C.
3.7 An integral pump located in the boilers main
hydraulic circuit circulates water through the primary
heat exchanger to either the central heating circuit or
D.H.W. heat exchanger, depending on the demand. In
the event of reduced or interrupted water circulation
in the central heating circuit, a system by-pass should
be fitted as far away from the boiler as possible.
Note: It is no longer permissible to utilise a non-
thermostatic controlled radiator as a by-pass.
3.8 Room temperature can be controlled by the use of
an external room thermostat or temperature regulator.
Note connection of the room thermostat is dependant
on the operating voltage of the thermostat. See
section 9.4 & 9.5 for details
3.9 Using an outdoor temperature sensor, which can
be connected directly to the main PCB, the boiler
operating temperature can be automatically adjusted
in line with outdoor climatic conditions.
3.10 The boiler incorporates an integrated clock,
which allows the setting of central heating periods
and the boiler’s control panel incorporates an LCD
display, which indicates the state of operation and
fault defect codes.
3. Boiler Characteristics.
07

vizo 24/28
4.1 Using the operating switch the boiler can be
set to operate either on domestic hot water
only or domestic hot water and heating.
Note: Domestic hot water demand draws
preference over heating. During heating periods
the boiler will automatically revert back to heating
mode, after a draw off of hot water, but there will
be a 45sec delay if the No.3 dipswitch is set to the
OFF position. See fig 19 page 21.
4.2 Depending on demand water is either diverted via
the three port valve to the secondary water-to-
water heat exchanger for domestic hot water or
directly to the heating system. Schematic
diagrams showing the flow within the boiler’s
central heating hydraulic circuit figure 2a and
D.H.W. hydraulic circuit figure 2b are given.
4.3 DOMESTIC HOT WATER MODE:
 On opening a hot water faucet the boiler
automatically responds to fire the boiler and
supply the water-to-water heat exchanger with hot
water via the three port valve, located on the
hydro-block. The boilers electronic control unit
automatically modulate the burner’s output to
maintain the required temperature at the faucet.
Hot water will continue to flow until the faucet is
closed and the boiler automatically shuts down.
Note that the pump will continue to run for a
further 10secs to dissipate the residual heat from
the boiler.
4.4 DOMESTIC HOT WATER AND CENTRAL
HEATING MODE:
 When heating demand is requested, power is on
and the timer and thermostat are calling for heat,
the boiler will fire automatically. An integral
pump is then energised and hot water from the
boilers primary circuit is circulated around the
central heating systems pipe-work and radiators.
When the demand for central heating is no longer
present, either the thermostat reaches temperature
or the time clock reaches the end of its set period,
the burner will shut down and the boiler will
revert to stand-by, waiting to respond to the next
heating or hot water demand. The pump will
continue to operate for a short period of time to
dissipate any excess heat from within the boiler’s
heat-exchanger. If during the heating period there
is a call for hot water this will take preference
over heating. When satisfied the boiler will then
supply the heating demand as required. Note
there may be a 45sec delay depending on how the
boilers dipswitches are set. See section 15.4 for
details.
4. Operation
Figure 2b
Figure 2a
Figure 2b
08

vizo 24/28
5.1 Installer Testing & Commissioning Tips
•The installer shall instruct the user in the operation
of the boiler, safety devices contained within the
boiler and instruction on how to re-pressurise the
system if the water pressure falls. The installer
should then hand over the instructions with the
Benchmark Logbook that has been completed.
•The user should be instructed to keep the
instructions in a safe place for servicing and future
reference.
•It is important to keep the boiler clear of dust
during the installation. In particular, do not allow
debris to enter the top of the boiler where the flue
connection is made. This may cause the fan outlet
to get blocked or combustion chamber to fill with
debris and will, of course, cause the boiler to fail to
ignite on first ignition. It is recommended that you
check the fan outlet before you light the boiler.
•Before you fit the boiler ensure that the pipe work
that you are installing is connected to the
appropriate connections on the boiler i.e. cold
water pipe to cold water inlet, hot water outlet to
the hot water tap etc.
•Because the boiler is actually operated, at the end
of each production stage, a small amount of water
is retained within the boiler when packed. Please
ensure that you spin the pump rotor manually
before firing the boiler.
•It is important that the boiler must be used in
conjunction with a Heat Line approved flue and all
flue connections are correctly sealed.
•Remember to flush out the system, both cold and
hot, in order to remove the debris from the system.
This should be done particularly where boilers are
being fitted to existing radiator circuits.
•Refer to BS 7593:1992 for the details to clean
DHW and Central heating system.
•This boiler has been factory set and does not
require any adjustments to the gas valve or fan
speed.
•Remember to release the small cap on top of the
auto air purge device on the pump, 1 turn, before
filling. This will ensure that air is removed as the
system fills.
•Do not use the pressure relief valve as a means
of flushing the system, please use the valve below
the pump. Discharging water from the system from
the pressure relief valve may allow water to seep
after you have left the job, causing the boiler to
lose pressure and debris to collect on the seating.
•The boiler is fitted with inlet filters both on the
cold water inlet and the central heating return. If
you are unable to obtain hot water at the faucet it is
likely that the cold water inlet valve filter has
become blocked, whilst blockage of the filter on
central heating return valve will cause the heater to
lock out at the overheat thermostat as the water
flow is reduced.
•If you are able to obtain hot water but not heating
it is also advisable to check the clock connections
and that the room thermostat and time clock are
calling for heat.
•Remember that after hot water draw off there is a
45 sec delay before the heating will fire up if No.3
dipswitch is in the OFF position, see fig 19 on
page 21
•When commissioning the boiler check the inlet
pressure is at 20mbar and burner pressure against
the Technical data on page 5.
•Note an anti-cycle delay time can be set up to a
maximum of 255 seconds by adjusting
potentiometer 2 as described in section 15.5 on
page 21.
If you experience any problems please refer to the
installation and commissioning guidelines within the
boiler instruction manual. If necessary, please contact
Heat Line
TM
Service Enquiries, in the UK, for further
advice and assistance on 0870 777 8318, in Ireland
call 01 466 4664.
NOTE – FOR INSTALLERS:
REMEMBER IT IS A LEGAL REQUIREMENT
TO COMPLETE THE BENCHMARK CODE OF
PRACTICE LOGBOOK BEFORE LEAVING
THE INSTALLATION.
5. General Installation
09

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5.2 The boiler is designed to operate on fully pumped,
pressurised sealed systems operating at a maximum of
3bar pressure and maximum design flow temperature of
85
0
C.
5.3 The boiler’s integral expansion vessel is pre-charged to
a pressure of 0.5bar and will accommodate a system
volume of 125 l. at an average water temperature of 75
0
C
and maximum system pressure of 3 bar. If the system
volume is more than 125 l. an additional expansion vessel
must be fitted to suit the size of the system. A typical
installation of an additional pressure vessel is shown
below in figure 3 below.
Figure 3.
5.4 The heating circuit should be designed and balanced to
give a 20
0
C temperature rise across the boiler flow and
return.
5.5 When fitting a new boiler to an existing system the
system must be thoroughly flushed in accordance with the
recommendations of BS7593 prior to installation.
5.6 It is recommended that the system should be protected
by an anticorrosion inhibitor. Failure to comply with this
requirement may invalidate your guarantee.
5.7 On installation it is important to ensure that the heat
exchanger is not a natural collecting point for air and
where possible, the system pipe work should have a
gradient to ensure any excess air is carried naturally to
other purpose made, air release points.
5.9 In high water volume systems or under floor heating
systems where prolonged operation of the boiler is
expected at temperatures below 60
0
C, a by-pass must be
installed on the boiler outlet in order to prevent
condensation forming inside the combustion chamber.
Failure to comply with this requirement will invalidate the
manufacturer’s guarantee.
5.10 The pressure relief discharge must be directed away
from any electrical equipment or where it could cause a
hazardous situation.
5.11 To enable adequate drainage of the system drain
cocks compliant with BS2879 must be fitted at the lowest
points in the system pipe-work.
5.12 To obtain the best hot water performance from your
boiler it is suggested that the cold water supply to the
boiler is the first draw off from the incoming mains
supply. Note that the boiler will not operate unless there is
a minimum pressure of 0.25bar with a flow rate of
2.5l/min. Where inlet pressures exceed 8bar, a pressure
regulator must be fitted to the cold water supply.
5.13 Where cold water mains are fitted with a water meter,
check valve(s) or loose jumper stopcock, a domestic hot
water mini-expansion vessel may need to be fitted.
5.14 Although the boiler is designed to inhibit the
formation of scale, in hard water areas above 200mg/l, a
proprietary scale reduced should be fitted in the cold water
supply to the boiler. Failure to comply may invalidate
your guarantee.
5.15 To obtain the best hot water performance from your
boiler it is suggested that supplies to faucets are run in
15mm copper, as short as possible and where practical, be
insulated to reduce heat loss.
5.16 The boiler incorporates a frost protection thermostat.
Therefore if the boiler will not be used for long periods of
time during cold weather, in order to avoid freezing the
electric supply must be left ON and all the central heating
isolation valves must be left open. The internal frost
thermostat will then operate the boiler if the temperature
falls too low. However, if the electrical supply is to be
turned off the boiler, the heating system and domestic hot
water circuit must be drained.
Flow
control
valve
Bypass
valve
Filling
device
Cold water
supply
Domestic
hot
water
Heating outlet
Flow
control
valve
Boiler
F
low
control
valve
Heating
return
Additional
expansion
vessel (if
required)
10

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6.1 If the boiler is to be installed in any room or
compartment, it requires no purpose made ventilation for
combustion air. If sited in a room containing a bath or
shower then particular reference is drawn to the current
I.E.E. Wiring Regulations and local Building Regulations.
6.2 If the Vizo24 / Vizo28 boiler is installed in a
compartment there must be purpose made ventilation for
cooling purposes.
6.3 The boiler is not suitable for external installation
unless protected by a purpose made building such as a
boiler house.
6.4 The following clearances are recommended for
installation purposes; 200mm above, 300mm below and
50mm at each side. 600mm is required at the front but this
may be upon opening a cupboard door.
6.5 The boiler must be sited at least 1m away from
flammable materials and heat sensitive walls must be
protected by appropriate insulation.
6.6 The wall on which the boiler is mounted must be
sufficiently strong enough to support the weight of the
boiler.
6.7 A condensate drain pipe must be fitted to allow
discharge of condensate to a drain or soakway.
Where possible condensate should be discharged into the
household internal drainage system. If this is not practical,
discharge can be made into an external drain. If neither of
the above options are possible then condensate must be
discharged into a purpose designed soakway.
oIt is recommended that any external condensate
pipe is insulated and increased to 32mm diameter
in order to prevent the condensate from freezing.
oTo avoid excessive condensation occurring within
the boiler flue the boiler should wherever possible,
be sited to ensure the shortest possible flue run is
utilised.
6.8 For compartment installation the requirements of
BS6798 and BS5440: Part 2 must be met.
The compartment must be of sufficient size to permit
access for inspection and servicing or the removal of
the boiler and any ancillary equipment.
Any space used for airing clothes or storage must be
separated from the appliance by a non-combustible
partition. Where the partition is formed from
perforated material, then the major dimension of the
apertures shall not exceed 13mm.
No combustible surface must be within 20mm of the
boiler casing without protection.
There must be 20mm clearance between the
compartment door and boiler case.
Where the boiler’s flue pipe passes through the airing
space, it must be protected by a non-combustible
sleeve or fire stop which has a minimum clearance of
20 mm from the flue pipe. In addition, if the flue pipe
passes through the partition then the clearance gap of
the flue pipe or its guard with the partition must not
exceed 13 mm.
6.9 When the boiler is intended for use with LPG it must
not be installed in a room or internal space below ground
level
..
6.
7.1 The flue terminal must be sited with minimum
clearances as specified in Figure 4. Note if pluming
becomes problematic or causes a nuisance a plume
management kit is available from your stockist.
.
7.2 Current regulations and standards require a
terminal guard to be fitted where the terminal is
accessible to touch or at risk of being damaged. All
wall mounted terminals sited within 2m of the level
which people have normal access, should be
adequately protected with a suitably sited guard
7.3 Where the flue terminates within 1m of a plastic
or painted gutter or within 500mm of painted eaves
then protection should be provided in the form of an
aluminium shield at least 1m in length, fitted to the
underside of the gutter or painted surface.
7.4 The flue should not be sited where the condensate
“plume” may give rise to a nuisance factor under
certain weather conditions.
6. Appliance Siting
NOTE:
If you have difficulty siting the flue in an
appropriate location your supplier will be happy to
supply a “anti-plume management kit”, which
discharges the flue products at a higher level.
7. Flue Terminal Location
11

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TERMINAL POSITION MINIMUM
DISTANCE
A- Directly below an openable window or other opening e.g. air brick 300 mm
B- Below gutters, soil pipes or drain pipes 75 mm
C- Below eaves 200 mm
D- Below balconies or car front roofs 200 mm
E- From vertical drain pipes and soil pipes 150 mm
F- From internal or external corners 300 mm
G- Above ground, roof or balcony level 300 mm
H- From a surface facing a terminal 600 mm
I- From a terminal discharging towards another terminal 1200 mm
J- From an opening in a car port (e.g. door, window) into a dwelling 1200 mm
K- Vertically from a terminal on the same wall 1500 mm
L- Horizontally from a terminal on the same wall 300 mm
M- Above an opening, air brick, opening windows, etc. 300 mm
N- Horizontally to an opening, air brick, opening windows, etc. 300 mm
P- Above roof level (to base of terminal) 300 mm
Q- From adjacent wall to flue 300 mm
R- From an adjacent opening window 1000 mm
S- From another roof terminal 600 mm
Internal Corner External Corner
Double Corners
Figure 4
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8.1 The boiler utilises a concentric flue arrangement
which consists of a 60mm-diameter inner flue and
100mm-diameter outer air inlet duct.
8.2. A standard 700+/-5mm flue kit (figure 5) is
supplied with the boiler, which can be routed to the
rear, left or right of the appliance by means of a 90
0
degree bend. The bend is connected to the boiler
using the screws provided and sealed with the gasket.
Fig.5
8.3. The 60/100cm flue pipes may be extended up to a
maximum of 2.5m using additional spare components
available from your supplier. This length can be
increased to 7m using the 80/125mm flue kit.
8.4. A vertical 60/100cm flue kit is also available
from your supplier up to a maximum length of 3m.
The terminal is suitable for a flat or pitched roof.
This length can be increased to 8m using the
80/125mm flue kit.
8.5. The flue restrictor, as shown in figure 6, supplied
with this boiler is NOT required.
8.6. The connection of vertical flue system is similar
to the Horizontal flue connection. The flue is
connected to the boiler via connection screws whilst
the sections are held together with the clamps
provided.
8.7. To avoid condensate dripping from the terminal
the flue should be installed with an upward gradient
(from the boiler) of 3
0
.
8. General Flue Info
Figure 6a
Note. F
or
each additional 90º elbow used the
maximum flue length must be reduced by 1.5 m,
whilst the use of 2 x 45º bends warrants a reduction
of 2m.
.
WARNING!
ONLY A HEATLINE APPROVED FLUE IS
TO BE USED WITH THIS PRODUCT.
FAILURE TO COMPLY WITH THIS
REQUIREMENT WILL INVALIDATE YOUR
GUARANTEE AND COULD LEAD TO
PROSECUTION.
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9.1 The boiler is supplied factory wired complete with
1.5 m of mains fly lead. All electrical connections to
the mains supply must be made in full accordance
with the current I.E.E. regulations.
9.2 The boiler must be connected to an effective earth
system. Using the cable supplied the boiler may be
connected via a 3 amp fused three pin plug to an
unswitched shuttered socket outlet. However if the
boiler is installed in a room containing a bath or
shower regulations dictate that disconnection must be
incorporated in the fixed wiring with a switch
provided for disconnection from the mains supply
having a contact separation of at least 3 mm on all
poles and fused at 3 amp.
9.3 The point of connection must be readily
accessible, at a distance no further than 1.5m adjacent
to the appliance and provide complete electrical
isolation for the boiler and control system.
9.4 The low voltage room thermostat terminal block
is located to behind of left side of the plastic cover
(figure 7). On connection of a voltage free room
thermostat to the boiler, the factory fitted bridge
across the room thermostat terminal connectors must
be removed. If a mains voltage thermostat is to be
used the please refer to figure 8.
9.5 Mains powered thermostats must be connected
directly to the mains circuit board as indicated in
Figure 8.Cut the existing link and connect the wires
into the thermostat circuit.
9.6 Ensure that the polarity of the mains connection is
correct as reversed polarity may cause the appliance
to malfunction.
9.7 While the boiler's main pcb, pump, three-way
valve and gas valve are supplied at 230V AC., all
other components and associated circuits are supplied
at low voltage.
9.8 On connecting the mains electrical supply to the
boiler, it is essential to ensure that electrical safety
checks for earth continuity, earth resistance, polarity
and short circuit are carried out prior to making the
final connection. A diagram of the boiler's electrical
circuit is given as figure 9.
9.9 Fuse Ratings
Bertelli & Partners Circuit Board
F1 – 3.15amp fast blow
F2 – 2amp fast blow
SIT Circuit Board
F1 – 2amp fast blow
F2 – 2amp fast blow
Warning: On no account must any external
voltage be applied to any of the terminals on the
heating control connection plug.
9. Electrical Connections
Figure 7
Figure 8
Figure 8
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10.1 Prior to installing the boiler check the contents
of the carton: Appliance, Valves (Fixing Jig
Optional), Wall Hanging Bracket, Mounting
Template Service, Installation and User Manual,
Guarantee Card and Benchmark Log Book. The
boiler dimensions are given in figure 10.
10.2 Ensure that the boiler is suitable for the gas
supply by checking the data plate, which is situated
on the inside of the control panel door, and that the
system and chosen boiler position is in accordance to
Sections 5, 6 and 7 of these instructions.
Dimension Vizo24 Vizo28
A 405 430
B 169 169
C 60/100 60/100
F 39 64
G 64 64
10. Boiler Installation
Important Note.
Connection to the mains electrical supply must
be maintained at all times in order to provide
domestic hot water, frost protection and pump
over-run facility. Ensure that the boilers
electrical supply is not interrupted by any
external controls.
Figure 11
Figure 10
TOP
BOTTOM
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10.3 Position the supplied template on the wall,
ensuring it is level both vertically and horizontally
(figure 11). Mark the boiler fixing jig (if required),
wall bracket fixing positions and flue outlet position
(rear flue only). For flue side exit from the boiler -
Mark the horizontal flue centre line on the rear wall.
Extend the horizontal line to the side wall allowing a
3
0
decline back towards the boiler, to enable
condensate to drain back through the boiler. Mark the
flue centre vertical line. ( figure 12.)
Figure 12.
10.4 When cutting the flue hole it is recommended
that a 105mm diameter core drill is used where both
internal and external access for the flue installation is
available. Where only internal access is available a
125mm diameter core drill should be used. (Note:
Please take adequate precautions to prevent debris
entering the boiler via the flue outlet).
10.5 Using a 8·5mm drill bit, drill the holes for fixing
jig (optional) and hanging bracket. Locate and secure
the supplied wall mounting bracket and fixing jig in
position (figure 13).
10.6 Mount the boiler onto the fixing bracket via the boiler
mounting slots, (figure 13).
10.7 Connect isolation valves assembled (on the fixing jig, if
used) to the boiler ensuring the washers are fitted correctly.
10.8 On installing the flue, determine the required length of
the outer air duct by measuring the distance 'L' (figure
14b) from the face of the external wall to the back of
boiler's elbow connecting collar. The measurement for the
inner flue duct will be 'L' + 20mm
10.9 Measuring from the back of the terminal connection,
mark distance 'L' onto the outer air duct. (figure 14a)
10.10 Cut the outer air duct only to the required length
ensuring that the cut is square and free from burrs.
10.11 Measuring from the back of the terminal connection, mark
distance 'L' + 20mm (figure 14) onto the inner flue duct and cut
the duct to size, ensuring that the cut is square and free from
burrs.
10.12 Pass the flue assembly through the wall and connect the
assembly to the boiler, ensuring that both the air and flue duct
joints are fully pushed home into the connecting elbow's collar.
10.13 With the flue and joints secured fit the flue trim to the
external wall surface using a suitable mastic. Note. Where
internal access only is available, the flue trim must be attached
to the flue assembly prior to passing the assembly through the
wall.
10.14 For maximum flue lengths refer to the Technical Data on
page 5 in this manual
10.15 Condensing type boilers must be connected to the
drainage system. A plastic drain must be fitted to allow
discharge of condensate to a drain.
Condensate should, if possible, be discharged into the internal
household draining system. If this is not practical, discharge can
be made externally into the household drainage system or a
purpose designed soak away. Note if a soakway is used the
drain must terminate at least 500mm from the external wall.
figure 13
figure 14a
figure 14b
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10.16 Extract the bottom part of condensate trap , by
turning anti-clockwise and fill it with approximately
50 cc water re-connecting it to the boiler. (Figure b).
10.17 Connect the condensate drainage pipe to the
drainage system. (Figure a) Note due to the acidic
nature of the condensate the drainage system must be
made of non-corrosive material such as plastic tubing.
10.18 Connect the domestic hot water, cold water
inlet, heating system flow & return and pressure relief
valve pipework to the boiler fittings, ensuring that the
pipework has been correctly flushed before final
connection.
10.19 The electrical connections to the boiler must be
in accordance to Section 9 of these instructions.
NOTE: Place the filling loop in a visible
accessible position and instruct the user how to
pressurise the system if there is a fall in
pressure.
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11.1 The gas supply pipe must be capable of supplying the
quantity of gas required by the boiler (see Technical Data, section
2, page 5) in addition to the demand of any other gas appliances
being serviced from that supply.
11.2 The internal diameter of the gas supply from the meter to
the boiler's gas inlet connection must not be less than 22mm.
11.3 The meter governor must be capable of delivering a
pressure of 20mbar (for natural gas).
11.4 On final connection of the gas supply to the boiler, the
complete gas installation including the gas meter, must be tested
for soundness and purged.
12.1 The boiler must not be operated without water.
12.2 On completion of the boiler installation and ensuring that
all water connections are correctly made the boiler may be filled
with water via the filling loop (not supplied with the boiler).
Ensure that two manual feed valves and boiler isolation valves
are open.
12.3 Release the cover cap of the boiler's automatic air vent
situated on top of the pump. (Figure 15)
12.4 The manual feed valves must be closed and the filling loop
disconnected once the pressure sensor, sited on the boiler’s
control panel, indicates a system pressure between 1.0 and 1.5
bar. Figure 15
Release cover
cap when filling
system
12.5 Check that all the water connections throughout the system
are sound and bleed each of the heating system’s radiators in
turn. As air is vented the system pressure may need topping back
up to 1.0bar.
12.6 Air must be vented from the boiler's pump by unscrewing
the pump’s integral vent plug and allowing water to bleed for a
few seconds. Take care not to allow water to splash onto any
electrical components.
12.7 When the system is bled of any air it must be re-filled until
the pressure shown on the display gauge indicates a system
pressure of 1.5bar.
12.8 If the pressure exceeds 1.5 bar discharge the excess
pressure from the system via a radiator valve or pipe connection.
Do not use the safety discharge valve as the valve seat may
become contaminated with debris and fail to re-seal.
1- D.H.W. temperature control 4- Function switch
2- C/heating temperature control 5- Timer
3- System pressure gauge 6- LED Display
13.1 C/heating and D.H.W. temperature controls: The
boiler's integral control unit monitors and adjusts both the
boiler’s hydraulic circuit and D.H.W. water outlet
temperatures by means of sensors located on the C/heating
and D.H.W. flow outlets. The sensors electrical resistance,
which is dependant on temperature, determines the current
passing through the control potentiometers located on the
control panel. The respective potentiometer control dial
allows manual setting of the maximum required temperature
(reference value) being between 30º and 85ºC for C/heating
and 35º and 64ºC for D.H.W. When the boiler operates in
heating or D.H.W. mode, the current received is compared
to the manually set reference value. The difference of the
two values operates the modulation of the gas valve
adjusting the useful heat output generated and stabilising the
temperature to within ±1ºC.
11. Gas Supply
12. Filling the System
Important Note.
In order to maintain the appliance’s
warranty; after initial filling the heating
system must be thoroughly flushed using a
propriety cleanser to remove foreign material
and contaminants.
13. Control Panel Functions
19