Biasi RIVA OV M110.18SM/OV User manual

Wall hung, fan flue, room sealed, high efficiency gas boiler
User manual and
Installation instructions
RIVA OV
Models G.C. Appl. No.
M110.18SM/OV 41-260-21
M110.30SM/OV 41-260-22
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
www.heatingspares247.com

!
Congratulations on your choice.
RIVA OV are condensing high efficiency sealed chamber fan flue gas boilers.
They are fully electronically controlled and have electronic ignition.
The materials they are made of and the control systems they are equipped with give you safety, a
high level of comfort and energy savings to allow you to get the greatest benefit out of independent
heating.
RIVA OV allow a higher efficiency by reducing the flue gas temperature such that the water vapour
formed during the combustion is condensed out.
This allows a gain of useful heat that otherwise would be lost.
Remember that...
✓The manual
–must be read thoroughly, so that you will be
able to use the boiler in a safe and sensible
way;
–must be carefully kept. It may be necessary
for reference in the future.
✓First lighting up must be carried out by
competent and responsible engineer.
✓The manufacturer
–disclaim all liability for any translations of the
present manual from which incorrect
interpretation may occur;
–cannot be held responsible for non-
observance of instructions contained in this
manual or for the consequences of any
procedure not specifically described.
Using the boiler...
✓Before lighting the boiler you are advised to
have a professionally qualified person check
that the installation of the gas supply
–is gas-tight;
–is of the correct gauge for the flow to the
boiler;
–is fitted with all the safety and control
devices required by the current Regulations.
✓Ensure that
–the installer has connected the condensate
outlet to a suitable drain pipe.
✓On detecting the smell of gas
–don’t operate any electrical switches, the
telephone or any device that may produce
sparks;
–open the windows and doors at once to
create a draught of air which will purge the
area;
–shut off the gas cocks;
–get the assistance of a qualified person.
✓Do not touch the appliance with parts of
the body that are wet or damp and/or bare
feet.
✓Do not block or modify the condensate
outlet and pipework.
✓In the case of structural work or
maintenance near the exhaust duct and/or
fume exhaust devices or their attachments,
turn off the appliance. On completion of the
work, have a professionally qualified person
check their efficiency.
✓Repairs (under guarantee) must be carried
out only by an approved engineer, using
genuine spare parts. Thus do no more than
switching off the boiler yourself (see the
instructions)
✓Your boiler allows heating up of water to a
temperature less than boiling point;
–must be connected to a central heating
system and/or a hot water supply system,
compatible with its performance and output;
–can be used only for those purposes for
which it has been specially designed;
–must not be touched by children or by those
unfamiliar with its operation;
–must not be exposed to weather conditions.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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!
✓During the operation it is quite normal that
the boiler produces a white plume of
condensation vapour from the flue terminal.
This is due to the high efficiency of the
appliance and may be particularly evident
with low outdoor temperatures.
Safe handling
of substances
Biasi products are manufactured in accordance with
ISO 9000 and do not, and will not contain any
hazardous materials or substances such as asbestos,
mercury or C.F.C.’s.
The appliance packaging does not contain any
substances, which may be considered a hazard to
health.
Combustion chamber panels
Material: mineral fibres
Known hazards – Some people can suffer reddening
and itching of the skin. Fibre entry in to the eye will
cause foreign body irritation, which can cause severe
irritation to people wearing contact lenses. Irritation
to respiratory tract.
Precautions – Dust goggles will protect eyes. People
with a history of skin complaints may be particularly
susceptible to irritation. High dust levels are only
likely to arise following harsh abrasion. In general,
normal handling and use will not present high risk,
follow good hygiene practices and wash hands
before touching eyes, consuming food, drinking or
using the toilet.
First aid – medical attention must be sought following
eye contact or prolonged reddening of the skin.
Appliance category l2H Gas G20 20 mbar
Country of destination: United Kingdom (GB) Ireland (IE)
This appliance conforms with the EEC directive 90/396 and, consequently, it has the right to make use of
the Biasi Riva OV brand name.
Moreover, the appliance conforms with the EEC directive 87/308 relative to the prevention and elimination
of radio disturbances.
The appliance is built to comply with the regulation now in force regarding gas appliance’s safety and the
European regulation now in force relative to safety of household and similar electrical appliances.
The manufacturer, in the continuous process to improve his products, reserves the right to modify the date
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.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
www.heatingspares247.com

Boiler installation and commissioning tips
✓The installation must be carried out by a
qualified person who will be responsible for
observing the current Regulations.
Installing the boiler...
✓Do not forget to remove the transit caps and
plugs from the boiler connections, these are
fitted to every boiler.
✓Keep the boiler clear of dust during
installation and in particular do not allow any
dust or debris to enter the top of the boiler
where the flue connection is made. It is
recommended that you put a dust sheet over
the top of the boiler until you are ready to
make the flue connection.
✓Remember to release the manual air vent
before filling the boiler. See the instructions
to identify the location of this device.
✓This boiler allows to control the flow
temperature of the central heating system at
very low levels.
In case of an underfloor heating system, a
temperature limiting device (e.g. a safety
thermostat) is recommended to stop the
boiler in case the water temperature exceeds
the design temperature.
✓You are strongly advised to flush out the
system both cold and hot in order to remove
system and installation debris.
✓It is also sensible to initially fire and
commission the boiler before connecting any
external controls such as a room thermostat.
By this method if you have a subsequent
problem following the addition of an external
control you can eliminate the boiler from your
fault analysis.
✓If the boiler is fitted with a digital
programmer, when setting the times for
automatic operation, remember that for
every “ON” time there must be an “OFF” time
to follow and that on every occasion you
enter a time you must also indicate which
days that you want the boiler to follow the
timed settings.
✓Some products incorporate an anti-cyclonic
time delay. It is normal when first switching
the boiler on for the boiler to operate on
heating for a few seconds then switch off.
After 3-4 minutes has elapsed the boiler will
then re-ignite and operate perfectly normally.
✓If you are in any doubts as to the installation
or operation of the boiler please read the
instruction manuals thoroughly and then if
necessary contact Biasi UK for advice and
assistance.
Please remember that if you are in any doubt about the installation of this product you can contact our
Technical Helpline on tel. [phone].
When installing, commissioning or servicing a gas appliance that incorporates a pre-mix burner and zero-
set governor, because it is not possible to measure an operating pressure the engineer should first check
that the gas supply is metered and ascertain whether it is possible to measure the gas rate. If the gas input
rate can be measured then the requirements of GSUIR 26(9) can be met, including any specific
requirements in manufacturers’ instructions.
If gas input rate cannot be measured then, to satisfy the intent of GSUIR 26(9), the engineer shall measure
the combustion quality of the appliance in accordance with BS 7967 or the manufacturers’ instructions.
If the engineer does not have the required equipment and no alternative test is specified by the
manufacturer then the appliance shall be turned off and disconnected as an un-commissioned appliance
until such time that equipment is available to undertake such tests.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
www.heatingspares247.com

TABLE OF CONTENTS
1Introduction . . . . . . . . . . . . . . . . . . . . . . . 0
1.1 Important Information . . . . . . . . . . . . . . . . 0
1.2 General Description . . . . . . . . . . . . . . . . . . 0
2Technical Specifications . . . . . . . . . . . . . . 0
2.1 Gas Categories. . . . . . . . . . . . . . . . . . . . . . . 0
2.2 Performance Data . . . . . . . . . . . . . . . . . . . . 0
2.3 General Specifications . . . . . . . . . . . . . . . . . 0
2.4 Overall Dimensions & Min. Clearances . . . . 0
2.5 Concentric Air / Flue Duct Specifications . . 0
2.6 Specification for Open Flued B33 Applications 0
2.7 Spec for Twin Flued (Type C53) Applications 0
2.8 Additional Concentric Flue Kits . . . . . . . . . 0
2.9 Appliance Hydraulic Circuit . . . . . . . . . . . . . 0
3Installation Requirements . . . . . . . . . . . . . 0
3.1 Statutory Requirements . . . . . . . . . . . . . . . . 0
3.2 Appliance Location. . . . . . . . . . . . . . . . . . . . 0
3.3 Flue Terminal Position . . . . . . . . . . . . . . . . . 0
3.4 Ventilation Requirements . . . . . . . . . . . . . . . 0
3.5 Condensate Disposal. . . . . . . . . . . . . . . . . . 0
3.6 Gas Supply. . . . . . . . . . . . . . . . . . . . . . . . . . 0
3.7 Central Heating systems . . . . . . . . . . . . . . . 0
3.8 Draining Tap . . . . . . . . . . . . . . . . . . . . . . . . . 0
3.9 Safety Valve Open Vented System . . . . . . . 0
3.10 Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0
3.11 Flow Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . 0
3.12 Water Treatment . . . . . . . . . . . . . . . . . . . . . . 0
3.13 Open Vented Water System. . . . . . . . . . . . . 0
3.14 Domestic Hot Water System . . . . . . . . . . . . 0
3.15 Sealed Water System. . . . . . . . . . . . . . . . . . 0
3.16 Safety Valve Sealed System . . . . . . . . . . . . 0
3.17 Expansion Vessel . . . . . . . . . . . . . . . . . . . . . 0
3.18 Pressure Gauge . . . . . . . . . . . . . . . . . . . . . . 0
3.19 Water Makeup . . . . . . . . . . . . . . . . . . . . . . . 0
3.20 Filling a Sealed Water System . . . . . . . . . . . 0
3.21 Electricity Supply . . . . . . . . . . . . . . . . . . . . . 0
3.22 External Controls . . . . . . . . . . . . . . . . . . . . . 0
4Appliance Installation. . . . . . . . . . . . . . . . . 0
4.1 Unpacking The Appliance . . . . . . . . . . . . . . 0
4.2 Preparing The Wall . . . . . . . . . . . . . . . . . . . . 0
4.3 Mounting The Appliance . . . . . . . . . . . . . . . 0
4.4 Central Heating Service Connections . . . . . 0
4.5 Gas Connection . . . . . . . . . . . . . . . . . . . . . . 0
4.6 Condensate Connection . . . . . . . . . . . . . . . 0
4.7 Air / Flue Duct Installation . . . . . . . . . . . . . . 0
4.8 Electrical Connections . . . . . . . . . . . . . . . . . 0
5Commissioning. . . . . . . . . . . . . . . . . . . . . . 0
5.1 Filling the Water System . . . . . . . . . . . . . . . 0
5.2 Commissioning the Appliance . . . . . . . . . . . 0
5.3 Final Checks. . . . . . . . . . . . . . . . . . . . . . . . . 0
5.4 Lockout / Reset Indication. . . . . . . . . . . . . . 0
5.5 Frost Protection . . . . . . . . . . . . . . . . . . . . . . 0
5.6 Overheat Protection . . . . . . . . . . . . . . . . . . . 0
5.7 Other Features . . . . . . . . . . . . . . . . . . . . . . . 0
5.8 Users Instructions. . . . . . . . . . . . . . . . . . . . . 0
5.9 Appliance Log Book. . . . . . . . . . . . . . . . . . . 0
5.10 Gas Conversion . . . . . . . . . . . . . . . . . . . . . . 0
6Routine Servicing. . . . . . . . . . . . . . . . . . . 0
6.1 Combustion Check . . . . . . . . . . . . . . . . . . 0
6.2 Gas Control Valve, Fan & Burner Assembly 0
6.3 Burner . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0
6.4 Ignition & Detection Electrodes. . . . . . . . . . 0
6.5 Combustion Chamber & Heat Exchanger . 0
6.6 Condensate Drain . . . . . . . . . . . . . . . . . . . . 0
6.7 Sealed Water System. . . . . . . . . . . . . . . . . 0
6.8 Re-assembly & Re-commissioning . . . . . . 0
6.9 Final Checks . . . . . . . . . . . . . . . . . . . . . . . 0
7Internal Wiring Diagrams . . . . . . . . . . . . 0
7.1 Functional Flow Wiring Diagram . . . . . . . . 0
8Fault Finding. . . . . . . . . . . . . . . . . . . . . . . 0
8.1 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . 0
8.2 Diagnostic LED Indicators . . . . . . . . . . . . . 0
8.3 Faulting Finding Codes . . . . . . . . . . . . . . . 0
8.4 Central Heating Fault Finding . . . . . . . . . . 0
9Short Parts List . . . . . . . . . . . . . . . . . . . . 0
USEINSTALLATIONMAINTENANCE
1
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
www.heatingspares247.com

2
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1Introduction
The Biasi Riva OV 18 and Riva OV 30 are high
effiency condensing, fully automatic, wall
mounted gas appliances suitable for room
sealed applications and for use with Natural gas
(G20) only. They are designed for use with either
sealed or open vented central heating systems.
The appliances incorporate a microprocessor
based, fully modulating pre-mix air/gas ratio
control system with direct burner ignition, which
provides a modulated heat output to central
heating (CH) demand.
The heat exchanger is constructed from
stainless steel, and there is the option for routing
the flow and return connections either via top or
bottom connections.
The appliances may be used with any certified
mains voltage room thermostat, and can operate
without the need for an automatic bypass valve,
however if thermostatic radiator valves are
installed it is recommended that one radiator is
fitted with lockshield valves, (normally in the
bathroom), to allow the pump overrun facility to
operate correctly.
The Biasi Riva OV 18 provides central heating at
outputs between 5.9kW (20,100 BTU/h) and
19.3kW (65,900 BTU/h).
The Biasi Riva OV 30 provides central heating at
outputs between 8.2kW (28,000 BTU/h) and
32.1kW (109,500 BTU/h).
The appliances also incorporate frost protection
as standard, however users are reminded that
this is not operational when the electrical supply
to the appliance is isolated.
Each appliance features an attractive white
powder coated casing with an inset control
panel. All flue systems are white powder coated
to give an attractive appearance to the
installation.
A standard horizontal concentric air/flue duct
terminal is available, (maximum duct length of
755mm (29 in)), suitable for room sealed
applications. The duct assembly is connected to
the appliance via a turret, which can be
orientated to provide different horizontal duct
directions. Extension ducts may be fitted in
accordance with and up to the maximum
dimensions stated in these instructions.
A vertical concentric outlet kit is also available
for installations where an outside wall is not
accessible or where it is desired to fit the duct
through the roof. Installation using the horizontal
or vertical duct is described in the main text of
these instructions and additional information is
provided in the flue kit for the vertical installation
option. (Note: If the vertical outlet kit is to be
used, access to the roof is necessary).
A special anti-plume kit is available. For more
information contact BIASI UK Ltd Technical
helpline: 0121 506 1350.
ONLY BIASI APPROVED FLUE KITS OR
EXTENSIONS MAY BE USED WITH THESE
APPLIANCES.
1.1.1 Important Information
IT IS A STATUTORY REQUIREMENT THAT
ALL GAS APPLIANCES ARE INSTALLED BY
COMPETENT PERSONS, (i.e. CORGI
REGISTERED INSTALLERS) IN ACCORDANCE
WITH THE SAFETY (INSTALLATION AND USE)
REGULATIONS (CURRENT EDITION). FAILURE
TO COMPLY WITH THESE REGULATIONS MAY
LEAD TO PROSECUTION.
These appliance have been tested and certified
in order to satisfy the necessary European
Directives and comply with the latest Building
Regulations, including the effiency requirements
of the SEDBUK scheme.
Gas Appliance Directive 90/396/EEC
Effiency of Hot Water Boilers Directive
92/42/EC
Low Voltage Directive 93/68/EEC
Electromagnetic Compatibility Directive
92/31/EEC
No modifications to these appliances should be
made unless they are fully approved by the
manufacturer. Appliance installation must be
carried out by a competent person and must
be in accordance with the current legislation in
force at the time of installation, in the country of
destination. The manufaturer’s instructions must
not be taken as overriding any statutory
requirements.
GAS LEAKS. DO NOT OPERATE ANY
ELECTRICAL SWITCHES, OR USE A
NAKED FLAME. TURN OFF THE GAS
SUPPLY. VENTILATE THE AREA BY
OPENING DOORS AND WINDOWS. CALL
OUT YOUR LOCAL GAS SUPPLIER.
USE
!
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
www.heatingspares247.com

3
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1.1.2 Control of Substances Hazardous to
Health
Under Section 6 of the Health and Safety at
Work Act 1974, it is required to provide
information on substances hazardous to health.
The adhesives and sealants used in this
appliance are cured and give no known hazard in
this state.
Insulation Pads - These can cause irritation to
the skin, eyes and the respiratory tract. If you
have a history of skin complaints you may be
susceptible to irritation. High dust levels are
usual only if the material is broken. Normal
handling should not cause discomfort, but follow
normal good hygiene and wash your hands
before eating, drinking or going to the lavatory. If
you do suffer irritation to the eyes or severe
irritation to the skin seek medical attention.
1.1.3 Gas and Electricity Consumer Council
(Energywatch)
Energywatch is an independent organisation,
which protects the interests of gas users. If you
need advice concerning energy issues, they may
be contacted on their consumer help line
number: 08459 060708, or via their web site;
http://www.energywatch.org.uk
1.2 Safety
Read these user manual instructions and the
user label (fitted on the decorative front panel)
carefully before attempting to operate the
appliance. Comply with all applicable warnings.
Do not interfere with any sealed components
and use the appliance only in accordance with
these instructions.
1.2.1 Current Gas Safety (Installation and
Use) regulations or the rules in force
It is the law that all gas appliances are installed
by a competent person in accordance with the
above regulations. Failure to install appliances
correctly could lead to prosecution. It is in your
own interest, and that of safety, to ensure that
the law is complied with. If the appliance is
damaged, turn off the appliance and consult a
CORGI registered installer.
If it is known or suspected that a fault exists on
the appliance it MUST NOT be used until the
fault has been rectified by a competent person.
1.2.2 Electrical Supply
This appliance must be earthed.
Supply: 230V ~ 50Hz fused at 3A.
This method of connection to the mains supply
must facilitate complete isolation of the
appliance. Either a 3A fused three pin plug and
un-switched shuttered socket outlet, or a 3A
fused double pole switch having a 3mm contact
separation in both poles, serving only the boiler
(and its external controls), may be used.
1.2.3 Clearances and Ventilation
It is not neccesary to have a purpose provided
air vent in the room or internal space in which a
room-sealed appliance is installed.
Cupboard or compartment ventilation is not
necessary for a room-sealed appliance
providing that the minimum clearances are
maintained.
1.3 Boiler Logbook
Please ensure that you have a Logbook supplied
with your appliance. This Logbook should be
completed by your installer to verify that the
correct installation and commissioning
procedure was followed.
Failure to complete the Logbook may result in
difficulties should a problem arise with your
appliance during the guarantee period. This
Logbook forms part of the industry’s Benchmark
code of practice for the installation,
commissioning and servicing of central heating
systems.
All CORGI Registered Installers carry a CORGI
ID card and have a registration number. Both
should be recorded in your Logbook. You can
check your installer is CORGI registered by
calling CORGI on 0870 401 2300.
1.4 Operating Instructions
Refer to Fig. 1
1.4.1 To light the Boiler
1 Switch on the electrical supply.
2 Turn the CH control knob to the midpoint
between minimum and maximum setting. The
display changes from 'o' to ' ' .
3 Ensure that all secondary controls, e.g.
programmer, room thermostat are calling for
heat.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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4
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4 The display changes to 'H'. When the burner
has lit there will be a small dot appearing in
the bottom right corner of the display.
5 If the burner fails to light the fan will stop.
Initially this may be due to air in the gas
supply. The boiler will automatically have five
attempts at ignition. After the five attempts it
may be necessary to RESET the boiler by
turning the control knob to RESET position
and repeat (2).
1.4.2 Control of Water Temperature
CH: Adjustable via the CH temperature control
knob to give radiator temperatures of between
30°C and 80°C. To operate the boiler more
efficiently it is recommended to set the CH
temperature about half way (between '+' and
'-'). Please check with your installer the size of
your radiators.
During periods of no heating requirement, this
control should be set to the Standby position.
Note: If the display shows a flashing 'H' the
boiler is in a service mode and the boiler will
fire continuously at minimum input.
This setting is for the convenience of the
Service Engineer ONLY.
1.4.3 To turn the Boiler off
For short or long periods
Switch the programmer and/or room thermostat
switch to the OFF position.
Note: The appliance is fitted with a frost
protection device. In the event of very cold
conditions, the pump may operate and the boiler
light for a few minutes to protect the appliance
and system from potential frost damage. This
can only function if the gas and electricity
supplies are maintained and the control knob on
the appliance is set to the STAND-BY position.
This function automatically operates the boiler
when the heating system water reaches
temperatures below 5ºC.
If either the gas or electricity services is to be
isolated during a period when frost is likely, the
water circuits must be drained.
1.4.4 Boiler overheat Thermostat
The appliance is fitted with two thermistors
located on the flow and return pipes. In the event
of overheating, the boiler will shut down and the
display will show '1'. Allow the boiler to cool,
then briefly turn the control knob to
STAND-BY/RESET position and then back to an
'on' position within TWO seconds.
If the fault persists, consult a CORGI registered
installer.
1.4.5 Diagnostic Digital Display
FASCIA PANEL, Figure 1
For fault finding, refer to the diagnostic chart
shown below, together with the notes given in
sections 8.3, 8.4 and 8.5.
Fault Finding Codes
In the event of the appliance failing to light, refer
to the Diagnostics Chart on the next page.
To RESET the boiler turn the control knob to the
STAND-BY/RESET position and back to an 'on'
position within TWO seconds.
1.5 General Care
The front panel, being a powder coated white
finish should be cleaned with a damp cloth and
mild detergent. Do not use abrasive cleaners.
1.6 Routine Servicing
To ensure continued efficient operation of the
appliance, it is recommended that it is checked
and serviced as necessary at regular intervals.
The frequency of servicing will depend upon the
particular installation conditions and usage but
in general once a year should be adequate. It is
law that any service work must be carried out by
a competent person such as British Gas or other
CORGI registered personnel.
Fig 1. Fascia Panel
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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5
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RESET LOCK-OUT CODES
LED CODE FAULT/EFFECT REASON
1Overheated appliance Water temperature greater than 105°C
2Water flow failure or Differential check faulty/ Sensor temperature differential incorrect
Flame for a short period only
3No gas or Lockout flame signal/ No flame, Low gas pressure.
Lockout after 5 ignition attempts No flame signal on ignition, or loss of
signal during operation
4Flue gas sensor/No flame Flue gas temperature greater than 95°C
BLOCKING CODES
LED CODE FAULT/EFFECT REASON
5Defective sensor/No flame Defective flow, return or flue sensor
6Defective gas valve/ 5 sec. flame signal after burner
Flame continues after demand ends is switched off
7Defective fan/No flame Missing or Erroneous RPM signal
APCB error/No flame Internal error
Activate BCC/No flame New BCC
CSafety system failure/No flame Failure of internal self checking system
EBCC error/No flame Incorrect /missing BCC
No flame No demand/Faulty connector
ODifferential check faulty/Flame for 15 seconds Water flow rate too low
PError in power supply/No flame Low mains voltage
No light indication Defective power supply
NOTE:
RPM SIGNAL - FAN SPEED SIGNAL IN REVOLUTIONS PER MINUTE
BCC - BOILER CHIP CARD (A SMALL MICROCHIP THAT PUSH FITS ONTO THE CONTROL PCB AND
ALTERS OPERATING PARAMETERS) SEE SECTION 7 FIG.31)
FAULT CODES 1-4 CAN BE RESET BY FOLLOWING THE PROCEDURE IN SECTION 1.4.5.
HOWEVER, IF ANY OTHER FAULT CODE IS SHOWING PLEASE CONTACT YOUR INSTALLER OR
BIASI UK LTD. TECHNICAL HELPLINE: 0121 506 1350.
1.7 Warning
If a gas leak is suspected or exists, turn the gas
OFF at the incoming mains (adjacent to the
meter). Do not operate any electrical switches.
Do not operate any electrical appliances. Open
all windows and doors. Do not smoke.
Extinguish all naked lights. Phone the Transco
24 hour emergency number immediately on
0800 111999. (Do not call from a mobile phone).
The boiler is fitted with a condensate trap.The
condensate drain point must not be modified or
blocked (see section 4.6 of the installation
manual).
1.8 Pluming from Terminal
Like all condensing boilers this appliance will
produce a plume of condensation from the flue
terminal. This is due to the high efficiency and
hence low flue gas temperature of the boiler. It
is normal and not a fault indication.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
www.heatingspares247.com

INSTALLATION
INSTALLATION
6
2Technical Specifications
2.1 Gas Categories
These appliances are certified to comply with
the requirements of EN 483 and EN 677 for use
in GB and IE (Great Britain and Ireland) using the
following gas categories:
Biasi RIVA OV 30, Biasi RIVA OV 18
I2H (G20 with a governed gas supply at 20 mbar
(8 in.wg) inlet pressure).
2.2 Performance Data - Biasi RIVA OV 30
Performance Data - Biasi RIVA OV 18
Central Heating Output
Non Condensing 80 - 60ºC
Max kW 30.0
BTU/h 102400
Min kW 8.2
BTU/h 28000
Condensing 50 - 30ºC
Max kW 32.1
BTU/h 109500
Heat Input
Max Rate Net kW 30.4
BTU/h 103700
Gross kW 33.8
BTU/h 115300
Min Rate Net kW 7.6
BTU/h 26000
Gross kW 8.4
BTU/h 28600
Gas Rate (after 10 mins operation - hot)
Max m3/h 3.22
Max ft3/h 113.7
Other Specifications
Seasonal Efficiency % 90.4
Seasonal Efficiency SEDBUK Band A
NOx Classification Class 5
Min Cen Heating Press Bar 0.1 (1m H20)
Max Cen Heating Press Bar 3.0
Max Cen Heat Flow Temp ºC 80
Min Cen Heat Flow Temp ºC 30
Central Heating Output
Non Condensing 80 - 60ºC
Max kW 18.0
BTU/h 61400
Min kW 5.9
BTU/h 20100
Condensing 50 - 30ºC
Max kW 19.3
BTU/h 65900
Heat Input
Max Rate Net kW 18.4
BTU/h 62800
Gross kW 20.4
BTU/h 69600
Min Rate Net kW 5.5
BTU/h 18800
Gross kW 6.1
BTU/h 20800
Gas Rate (after 10 mins operation - hot)
Max m3/h 1.95
Max ft3/h 68.9
Other Specifications
Seasonal Efficiency % 90.3
Seasonal Efficiency SEDBUK Band A
NOx Classification Class 5
Min Cen Heating Press Bar 0.1 (1m H20)
Max Cen Heating Press Bar 3.0
Max Cen Heat Flow TempºC 80
Min Cen Heat Flow Temp ºC 30
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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INSTALLATION
7
2.3 General Specifications
General Specifications - Biasi RIVA OV 30
Total Weight (full) kg 38.1
Total Weight (empty) kg 36.1
Max Lift Weight kg 28.1
Total Water Capacity l 2.0
Electrical Supply 230V 50Hz Fuse 3A
Internal Fuse T4H 4A 250V
Max Power Consumption W 46
IP Rating IP 20
Flue Gas Temp
Nat Gas 80/60 ºC 73
Flue Gas Temp
Nat Gas 50/30 ºC 41
CO2Value Max Rate %9.2±0.3 Case on
(Nat Gas)%9.0±0.2 Case off
CO2Value Min Rate % 8.9 ± 0.1
(Nat Gas) ref only
CO Value Max Rate % 0.01 ± 0.005
(Nat Gas)
Flue Products mass g/s 13.7
flow rate (Nat Gas)
Gas Valve Offset
@ min rate Pa -3.0
Connections - Biasi RIVA OV 30
Gas 15mm compression
CH Flow 22mm tail
CH Return 22mm tail
Condensate Drain 21.5 - 22mm
plastic overflow pipe
General Specifications - Biasi RIVA OV 18
Total Weight (full) kg 32.6
Total Weight (empty) kg 31.3
Max Lift Weight kg 24.7
Total Water Capacity l 1.3
Electrical Supply 230V 50Hz Fuse 3A
Internal Fuse T4H 4A 250V
Max Power Consumption W 30
IP Rating IP 20
Flue Gas Temp
Nat Gas 80/60 ºC 74
Flue Gas Temp
Nat Gas 50/30 ºC 43
CO2Value Max Rate %9.2±0.3 Case on
(Nat Gas)%9.0±0.2 Case off
CO2Value Min Rate % 8.4 ± 0.1
(Nat Gas) ref only
CO Value Max Rate % 0.01 ± 0.005
(Nat Gas)
Flue Products mass g/s 8.3
flow rate (Nat Gas)
Gas Valve Offset
@ min rate Pa -3.0
Connections - Biasi RIVA OV 18
Gas 15mm compression
CH Flow 22mm tail
CH Return 22mm tail
Condensate Drain 21.5 - 22mm
plastic overflow pipe
Biasi RIVA OV 18
A310 mm
C150 mm
D97 mm
E100 mm
F694 mm
G200 mm
H540 mm
I400 mm
J200 mm
K5mm
L5mm
M200 mm
Biasi RIVA OV 30
A350 mm
C150 mm
D97 mm
E100 mm
F694 mm
G200 mm
H540 mm
I400 mm
J200 mm
K5mm
L5mm
M200 mm
2.4 Overall Dimensions and Minimum Clearances
Fig 2. A
C
E
D
F
HG
I
J
K
L
M
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8
2.5.1 Fitting the Flue System
Refer to the assembly instructions contained
within the chosen flue kit packaging for the
correct assembly and installation.
In general, it has to be taken in consideration
that the horizontal sections of the flue pipe must
have an horizontal sloping not less that 1.5 deg.
(25 mm per metre) towards the boiler.
In the standard horizontal flue kit (Fig. 3) the flue
pipe is angled within the air duct therefore the air
duct must be horizontally installed.
If one or more extensions have to be used they
must be adequately supported so that there is
not sag in the flue pipe and a minimum fall of 1.5
deg. (25 mm per metre) over the whole length
towards the boiler is ensured.
Before fitting the flue system, ensure that the
flue gasket is fitted to the boiler.
2.5.2 Choice of flue
The following flue kits are available for
connecting to the boiler:
Standard horizontal flue kit (Fig. 3.)
Co–axial 60/100mm - nominal length 1m
This kit is normally supplied with the boiler and
can be fitted to allow discharge to the rear or
either side of the boiler via the flanged boiler
adapter elbow. Minimum length required is
250mm. Maximum equivalent length of 10
metres can be achieved utilising extensions.
This flue system can only be used to discharge
horizontally, it is not designed to enable
termination in the vertical plane.
Vertical kit with 90º elbow (Fig. 3.)
Co–axial 60/100mm
Supplied with a straight flanged adapter a co-
axial elbow and a co-axial pipe with terminal,
this kit allows for a vertical rise of 0.5 m from the
boiler. In all circumstances the flue terminal must
discharge horizontally and the equivalent flue
length must not exceed 10 metres.
Elbows 45º & 90º (Fig. 3.)
Co–axial 60/100mm
Elbow kits enable the standard flue kits to be
offset to overcome obstructions or ensure the
correct clearances for the flue terminal. Each
elbow used in addition to the standard flanged
elbow reduces the overall acceptable length of
the flue system as follows:
45º reduce length by 0.5 m.
90º reduce length by 1 m.
Vertical - roof kit (Fig. 3.1.)
This kit allows vertical termination of the flue
pipe through the roof. The kit is 1.2 m in length.
Extension pieces (Co-axial) are also available
which allows the flue system to be extended to
a total overall maximum permissable length.
Optional 45º and 90º elbows can be used to
offset the flue route.
Each additional elbow reduces the overall
acceptable length of the flue system as follows:
45º reduce in length by 0.5 m.
90º reduce in length by 1 m.
Fig. 3.
Fig. 3.1.
INSTALLATION
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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INSTALLATION
9
2.5.3 Anti-pluming kit
If the standard horizontal flue kit is likely to
cause nuisance to neighbours or buildings,
because of excess pluming, then this particular
flue kit raises the flue gas outlet point to a higher
elevation with the minimum amount of changes.
The flue gas duct is teed-off from the concentric
part and the air in-take remains at the lower level
(see Figure 3.2.).
If choosing this option then the external flue duct
length should be taken into account when
calculating equivalent flue length.
For installation details refer to the flue kit
instructions.
2.6 Additional Concentric Flue Kits
The following additional concentric kits are
available as optional extras.
Flue Extension Ducts - 1 m and 500 mm long,
(each duct extends the flue length by up to 950
mm and 450 mm respectively).
Raised Horizontal Flue - For use with elevated
horizontal flues.
For installation details refer to the instructions
provided with the individual flue kits.
These optional kits may be used with the
standard flue kits to produce an extensive range
of flue options, providing that the following rules
are strictly obeyed.
a) The maximum/minimum permissible length of
the room sealed flue system are:
Horizontal flue terminal (all orientations)
maximum 10 m (393 in)
Horizontal flue terminal (rear exit)
minimum 250 mm (10 in)
Vertical flue terminal
maximum 12 m (472 in)
Vertical flue terminal
minimum 600 mm (23.5 in)
The 'equivalent' flue length must not exceed
the maximum values stated.
b) The standard terminal must always be fitted
horizontally; horizontal ducts must have a
minimum continuous fall towards the
appliance of 1.5°. This ensures condensate
runs back into the appliance from the flue
system. The vertical terminal must always be
used if a vertical outlet is required.
c) The concentric flue system must use either a
flanged elbow or a raised horizontal flue
socket at the entry/exit to the appliance.
d) All joints must be correctly made and
secured in accordance with the installation
instructions. When cutting ducts, avoid
swarf, uneven and sharp edges to maintain
duct integrity.
Refer to Figures 2 and 3 to determine which
option kits are required before commencing
the installation. Instructions for installing the
appliance with a horizontal flue and straight
extension ducts are included in the main text
of these instructions (section 4.7).
Fig. 3.2.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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INSTALLATION
10
2.7 Appliance Hydraulic Circuit
Fig. 4.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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11
3Installation Requirements
3.1 Gas Categories
GAS SAFETY (INSTALLATION AND USE)
REGULATIONS 1998 (AS AMENDED)
The appliance is suitable only for installation in
GB and IE and should be installed in accordance
with the rules in force.
In GB, a CORGI Registered Installer must carry
out the installation. It must be carried out in
accordance with the relevant requirements of the:
Gas Safety (Installation and Use) Regulations
The appropriate Building Regulations either The
Building Regulations, The Building Regulations
(Scotland), Building Regulations (Northern
Ireland).
The Water Fitting Regulations or Water
Byelaws in Scotland.
The Current I.E.E Wiring Regulations.
Where no specific instructions are given,
reference should be made to the relevant British
Standard code of Practice.
In IE, the installation must be carried out by a
Competent Person and installed in accordance
with the current edition of I.S.813 "Domestic Gas
Installations", the current Building Regulations
and reference should be made to the current
ETCI rules for electrical installation.
It should also be in accordance with the relevant
recommendations in the current editions of the
following British Standards and Codes of
Practice: BS 5449, BS 5546, BS 5440-1, BS
5440-2, BS 6798, BS 6891, Institute of Gas
Engineer document IGE/UP-7, BS 7074
(expansion vessel) and IS813 for IE.
IMPORTANT NOTE: Manufacturer's instructions
must NOT be taken in any way as overriding
statutory obligations.
3.2 Appliance Location
The following limitations MUST be observed
when siting the appliance:
a) The appliance is not suitable for external
installations. The position selected for
installation should be within the building,
unless otherwise protected by a suitable
enclosure and MUST allow adequate space
for installation, servicing and operation of the
appliance and for air circulation around it
(Section 2.4 and 3.4).
b) This position MUST allow for a suitable flue
system and terminal position. The appliance
must be installed on a flat vertical wall, which
is capable of supporting the weight of the
appliance and any ancillary equipment.
c) If the appliance is to be fitted in a timber
framed building it should be fitted in
accordance with the British Gas publication
'Guide for Gas Installations In Timber Frame
Housing', Institute of Gas Engineers
document IGE/UP-7. If in doubt, advice must
be sought from the Local Gas Supplier.
d) The appliance is approved to a protection
rating of IP20. Therefore if the appliance is to
be installed in a room containing a bath or a
shower, any electrical switch or control
utilising mains electricity must be so situated
that it cannot be touched by a person using
the bath or shower. Attention is drawn to the
requirements of the current BS 7671 (I.E.E
Wiring Regulations) and in Scotland the
electrical provisions of the Building
Regulations applicable in Scotland. (This
section under review!)
3.3 Flue Terminal Position
Detailed recommendations for flue installation
are given in BS 5440-1. The following notes are
for general guidance.
a) The appliance MUST be installed so that the
terminal is exposed to the external air.
b) It is important that the position of the terminal
allows free passage of air across it at all
times.
c) It is ESSENTIAL TO ENSURE that products of
combustion discharging from the terminal
cannot re-enter the building or any other
adjacent building, through ventilators,
windows, doors, other sources of natural air
infiltration, or forced ventilation / air
conditioning.
d) The minimum acceptable dimensions from
the terminal to obstructions and ventilation
openings are specified in Figure 5.
e) If the terminal discharges into a pathway or
passageway check that combustion products
will not cause nuisance and that the terminal
will not obstruct the passageway.
INSTALLATION
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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INSTALLATION
12
f) Where the lowest part of the terminal is fitted
less than 2 m (78 in) above the ground, above
a balcony or above a flat roof to which people
have access, the terminal MUST be protected
by a purpose designed terminal guard.
g) The air inlet / flue outlet MUST NOT be closer
than 25 mm (1 in) to combustible material.
h) Condensing appliances have a tendency to
form a plume of water vapour at the terminal
under certain operating conditions. This is
normal but positions where this would cause
damage or a nuisance should be avoided.
Consideration should be given to the
dispersal of the plume in terms of adjacent
surfaces and neighbouring properties. A
special flue terminal, is available to raise the
flue discharge point; use of this terminal will
limit the maximum flue length available. For
further information contact: BIASI UK Ltd
Technical helpline: 0121 506 1350.
3.4 Ventilation Requirements
Detailed recommendations for air supply are
given in BS 5440-2.
The following notes are for general guidance.
a) It is not necessary to have a purpose
provided air vent in the room or internal space
in which a room-sealed appliance is installed.
b) Cupboard or compartment ventilation is not
necessary for a room-sealed appliance
providing that the minimum clearances are
maintained.
c) If the appliance is installed in a room or
internal space with other opened flued
appliances, the aggregate maximum rated
input shall be used to determine the air vent
free-area. (BS 5440-2 Table 2).
d) Where an open flued system is used, and the
flue duct air inlet is within a compartment
then high and low level air vents are
necessary in the compartment, the size of the
vents should be calculated in accordance
with BS 5440-2 Table 2.
The minimum acceptable spacing from the
terminal to obstructions and ventilation openings
are specified in Fig. 5.
Terminal Position mm
A. Directly below a window or other opening. . 300
B. Below gutters, soil pipes or drain pipes. . . . . 75
C. Below eaves . . . . . . . . . . . . . . . . . . . . . . . . . 200
D. Below balconies*. . . . . . . . . . . . . . . . . . . . 2500
E. Below car port roof . . . . . . . . . . . . . . . . . . . . NO
F. From vertical drain pipes and soil pipes . . . 150
G. From internal corners** . . . . . . . . . . . . . . . 1000
H. From external corners . . . . . . . . . . . . . . . . . 300
I. Above ground or balcony level. . . . . . . . . . . 300
J. From a surface facing a terminal . . . . . . . . 2500
K. From a terminal facing a terminal. . . . . . . . 2500
L. From an opening in the car port
(e.g. door, window) into dwelling. . . . . . . . . . NO
M. Vertically from a terminal in the same wall. . 500
N. Horizontally from a terminal in the same wall300
O. Above the roof pitch with roof slope less
than or equal to 30º . . . . . . . . . . . . . . . . . . . 350
Above the roof pitch with roof slope
more than 30º . . . . . . . . . . . . . . . . . . . . . . . . 600
P. From wall face . . . . . . . . . . . . . . . . . . . . . . . 600
Q. From, above or to side of an opening . . . . . 300
*Wherever practicable to do so, the flue should be
extended beyond the perimeter of the balcony.
** Consideration should be given to adding
protection against condensate to the adjacent
structure
Fig. 5.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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INSTALLATION
13
3.5 Condensate Disposal
The condensate drain connection is suitable for
either 21.5 mm or 22 mm plastic push fit or
adhesive overflow pipes and fittings. It should be
piped to drain, preferably within the building,
maintaining a continuous 2.5° fall away from the
appliance. If the drain is routed to outside it
should be to a drain or soak away, and any
external pipe work should be in 32 mm.
Insulation to protect from freezing in cold
weather conditions is also advisable.
If the appliance is installed in a garage all
pipe work should be in 32 mm. Ensure that
the condensate discharge system complies
with any local regulations in force.
3.6 Gas Supply
a) The Gas Supplier should be consulted at the
installation planning stage in order to
establish the availability of an adequate
supply of gas.
b) An existing service pipe MUST NOT be used
without prior consultation with the Gas
Supplier.
c) A gas meter can only be connected by the
Gas Supplier or by their contractor.
d) An existing meter and/or pipe work should be
of sufficient size to carry the maximum
appliance input plus the demand of any other
installed appliance. (BS 6891: 1988).
A minimum of 22 mm diameter pipe work is
recommended within 1 m of the appliance
gas cock.
e) Natural gas appliances: The governor at the
meter must give a constant outlet pressure of
20 mbar (8 in.wg) when all appliances on the
system are running.
f) The gas supply line should be purged.
WARNING: Before purging open all doors and
windows, also extinguish any cigarettes,
pipes, and any other naked lights.
g) The complete installation must be tested for
gas tightness.
3.7 Central Heating System
a) The appliances are designed for open vented
central heating water systems, but may be
fitted to a sealed central heating system
provided the necessary components, such as
expansion vessel and pressure safety relief
valve are fitted to the system. Refer to Figure
8 for a typical open vented system design,
which incorporates radiators, and a drain
facility that must be provided at the lowest
point in the system to allow complete drain
down.
b) The installation should be designed to
operate with a flow temperature of up to
95°C.
c) If a sealed system is to be used then only a
competent person must fill it.
d) The hydraulic resistance curves for the
appliances are given in Figure 6.
e) If thermostatic radiator valves are fitted, one
radiator must be fitted with two lock shield
valves, to enable correct operation of the
pump-overrun facility.
f) The following paragraphs outline the
specifications of the items fitted to the
appliances.
Appliance Hydraulic Resistance
RIVA OV 30
RIVA OV 18
3.8 Draining Tap
A draining tap must be provided at the lowest
point of the system, which will allow the entire
system and hot water system to be drained.
Draining taps shall be to the current issue of BS
2879.
0
56789101112 13 14 15 16 17 18 19 20 21 22 23 2
4
0.5
1
1.5
2
2.5
3
3.5
4
Pressure Drop (m H20)
Flow Rate ltr/min
Fig. 6.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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INSTALLATION
3.9 Ventilation Requirements
A safety valve need not be fitted to an open
vented system. (See 3.16 for sealed systems)
3.10 Pump
The pump should be fitted on the flow pipe from
the boiler and have isolating valves each side.
A variable duty pump should be set to give a
temperature difference of no greater than 20°C
between the flow and return, with the boiler
controls set at "MAX", which is approximately
80°C to give a flow rate as shown in table 1.
See figure 6 for pressure loss of the boiler.
High resistance microbore systems may require
a higher duty pump.
3.11 Flow Rate
If it is necessary to alter the flow rate, the system
can be fitted with a lockable balancing valve in
the main flow or return pipes shown as valve "A"
in figure 7. The flow rate through the boiler must
not be allowed to fall below that given in table 1.
Table 1. Flow Rate
MINIMUM FLOW RATE
200 l/h
This is equal to 20°C differential at minimum
heat input.
3.12 Water Treatment
WATER TREATMENT, CLEANSING AND
FLUSHING THE HEATING SYSTEM
NOTE: British Standard BS7593: 2006 stresses
the importance of cleansing and flushing of the
system to ensure it continues to run efficiently
with the minimum of maintenance necessary.
Biasi UK Ltd fully supports this professional
approach and recommends that the system is
cleansed with an effective chemical cleanser and
protected long term with a suitable inhibitor. Such
products are available from Fernox and Sentinal.
3.13 Open Vented Water System
The boiler must be supplied from an unrestricted
water supply taken from a feed and expansion
cistern situated at a maximum height of 27
metres (90ft) above the boiler.
The cold feed must be 15mm minimum size.
The vent must rise continuously and be
unrestricted.
It is important that the relative positions of the
pump, cold feed and open vent are as shown in
figure 9.
3.14 Domestic Hot Water Cylinder
SINGLE FEED INDIRECT CYLINDERS ARE NOT
SUITABLE
The domestic hot water cylinder must be of the
double feed fully indirect coil type.
3.15 Sealed Water Systems
The installation must comply with the appropriate
requirements of the current issue of BS4814,
BS5449, BS6759, BS6798 and BS7074 Part 1
and 2.
See figure 7 for a suggested layout.
3.16 Safety Valve Sealed System
A safety valve must be fitted to a sealed system.
It shall be preset, non-adjustable with a lift
pressure of 3 bar, incorporating seating of a
resilient material, a test device and a connection
for drain.
The drain from the safety valve must be routed
outside the building, must not discharge above
an entrance or window or any type of public
access area, be clear of any electrical fittings and
positioned so that any discharge can be seen.
3.17 Expansion Vessel
A diaphragm type expansion vessel, conforming
to the current issue of BS4814 (see also BS7074
Part 1 and 2) must be connected at a point close
to the inlet side of the circulating pump, see the
diagrammatic layout, figure 7 unless laid down
differently by the manufacturer.
The expansion vessel volume depends on the
total water system volume and the initial system
design pressure. For any system an accurate
calculation of vessel size is given in the current
issue of BS5449 and BS7074 Part 1.
Example: For an initial design pressure of 0.7 bar,
the minimum total vessel volume required is
0.063 x Total System Volume.
Note: A higher initial design pressure requires a
larger volume expansion vessel.
The charge pressure must not be less than the
static head of the system, that is, the height of
the highest point of the system above the
expansion vessel.
14
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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INSTALLATION
15
Sealed Water System
Fig. 7.
NOTE: No automatic by-pass
required. However it is
recommended to leave one
radiator open and to fit a
system bypass in the DHW
circuit to ensure pump over-
run functionality.
The water content of the boiler is given in 2.3
General Specifications.
Expansion Vessel Requirements
3.18 Pressure Gauge
A pressure gauge with a set pointer and covering
at least 0 to 4 bar (0 to 60 lb/in) shall be fitted
permanently to the system in a position where it
can be seen when filling the system.
3.19 Water Makeup
Provision should be made for replacing water
loss from the system using a make up bottle
mounted in a position higher than the top point of
the system, connected through a non-return
valve to the return side of either the heating
circuit or the hot water cylinder.
Alternatively, provision for make up can be made
using a filling loop.
3.20 Filling a Sealed Water System
Provision for filling the system at low level must
be made, see figure 7. There must be no
permanent connection to the mains water supply,
even through a non-return valve.
CONTROLS. As a minimum it is recommended
that a room thermostat be installed to control the
appliance. Thermostatic radiator valves may be
fitted to the system, however they must not be
fitted in the room where the room thermostat is
fitted. There must be at least one radiator
installed with lock shield valves that should not
be closed. Further guidance can be obtained
from the Domestic Heating and Hot Water Guide
to the building regulations.
Vessel charge and bar 0.5 0.75 1.0 1.5
initial system pressure
Total water content
of system using 8 L
(1.54 gal) capacity L 96 84 73 50
expansion vessel
supplied with appliance.
For systems having a
larger capacity multiply
the total system
capacity in litres (gallons) 0.0833 0.093 0.109 0.156
by these factors to
obtain the total
minimum expansion vessel
capacity required in litres.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
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INSTALLATION
16
Open vent water system
with flow and return
connected to bottom
pipes.
Fig. 8.
NOTE: No automatic
by-pass required.
However it is
recommended to leave
one radiator open and
to fit a system bypass
in the DHW circuit to
ensure pump over-run
functionality.
Open vent water
system with flow
and return
connected to top
pipes.
3.21 Electricity Supply
a) Wiring external to the appliance must be in
accordance with the current I.E.E Wiring
regulations (BS 7671) for electrical installation
and any local regulations, which apply.
b) The mains cable must be at least 0.75 mm2
(24/0.2 mm) PVC insulated to BS 6500 table
16.
c) THIS APPLIANCE MUST BE EARTHED.
Failure to provide a satisfactory earth
connection will result in appliance
malfunction.
The RIVA OV appliances may be used with any
certified programmer/room thermostat, as
described in section 4. For further information
contact: BIASI UK Ltd Technical helpline: 0121
506 1350.
3.22 External Controls
d) The method of connection to the mains
supply must facilitate complete electrical
isolation of the appliance. Either a 3A fused
three pin plug and un-switched shuttered
socket outlet, both complying with BS 1363,
or a 3A fused double pole switch having a 3
mm contact separation in both poles and
serving only the boiler (and its external
controls) may be used.
Fig. 9.
Unit 3A, Thornton Road Ind. Estate Off Hockney Road Bradford, BD8 9HQ
01274 488 388
www.heatingspares247.com