Beretta NOVELLA 24-31-45 RAI User manual

NOVELLA
24-31-45 RAI
24-31 RAI PV
BOILERS
CAST IRON
BASE
INSTALLATION MANUAL

INSTALLATION MANUAL
2
The following symbols are used in this manual:
b CAUTION! = Indicates actions that require caution and adequate preparation
a STOP! = Identifies actions that you MUST NOT do
Novella boilers conform to the basic requirements of the following directives:
• Gas Appliances Directive 2009/142/CE
• Boiler Efficiency Directive 92/42/CEE
(✫✫)
• Electromagnetic Compatibility Directive 2004/108/CE
• Low Voltage Directive 2006/95/CE
Novella boilers are therefore CE marked.
0694

3
CONTENTS
1 SAFETY INFORMATION AND PRECAUTIONS ........................................ 4
2 DESCRIPTION OF THE APPLIANCE ........................................................ 5
2.1 Description of the appliance ...............................................................................................................5
2.2 Optional accessories ..........................................................................................................................5
2.3 Main parts of the boiler .......................................................................................................................6
2.4 Control panel ......................................................................................................................................7
2.5 Technical specifications ......................................................................................................................7
2.6 Identification........................................................................................................................................8
2.7 Material supplied.................................................................................................................................9
2.8 Handling..............................................................................................................................................9
2.9 Overall dimensions and water fittings...............................................................................................10
2.10 Water circuit ......................................................................................................................................11
2.11 Wiring diagram..................................................................................................................................13
3 INSTALLATION ......................................................................................... 14
3.1 Installation standards........................................................................................................................14
3.2 Place of installation...........................................................................................................................14
3.3 Installation in existing systems .........................................................................................................14
3.4 Water connections ............................................................................................................................15
3.5 Electrical connections .......................................................................................................................15
3.6 Gas connections ...............................................................................................................................17
3.7 Gas supply conversion .....................................................................................................................17
3.8 Flue gas vent and air intake .............................................................................................................19
3.9 Filling the water circuit ......................................................................................................................19
3.10 Emptying the water circuit ................................................................................................................20
4 START-UP AND FUNCTIONING .............................................................. 21
4.1 Preliminary checks............................................................................................................................21
4.2 Ignition ..............................................................................................................................................21
4.3 Final checks......................................................................................................................................23
5 SHUT-DOWN ............................................................................................ 24
6 MAINTENANCE ....................................................................................... 25
6.1 Scheduled maintenance ...................................................................................................................25
6.2 Extraordinary maintenance...............................................................................................................25
7 OPTIONAL ACCESSORIES ..................................................................... 26

INSTALLATION MANUAL
4
1 SAFETY INFORMATION AND PRECAUTIONS
b This manual and the operation manual
associated with it form integral parts
of the product. Make sure that they are
always kept with the boiler even if it is
transferred to another owner or user, or
re-installed elsewhere. If you damage or
lose this manual, order a replacement
immediately from your local Technical
Assistance Service.
b The boiler must only be installed and
serviced by qualified personnel, in con-
formity to applicable legislation (in Italy,
law 46 of the 05/03/1990) and applica-
ble technical standards (in Italy, UNI-
CIG 7129 and 7131 standards and
subsequent updates thereto).
b The boiler must only be used for the pur-
pose for which it is designed. The manu-
facturer declines all responsibility, con-
tractual or other, for damage to property
or injury to persons or animals caused
by improper installation, adjustment,
maintenance or use.
b As soon as you open the packaging,
check immediately that the contents are
all present and undamaged. Contact the
reseller from whom you purchased the
product if you notice any problems.
b The safety valve must be connected to
a suitable collection and drain system.
The manufacturer declines all responsi-
bility for damage caused by the opera-
tion of an improperly connected safety
valve.
b The following instructions must be pas-
sed on to the user on installation of the
boiler.
- If water leaks from the boiler, turn off the
water supply and contact the manufactu-
rer’s Technical Assistance Service imme-
diately.
- Periodically check that operating pressu-
re in the water circuit is over 1 bar. If
necessary, contact the manufacturer’s
Technical Assistance Service to arrange
servicing by professionally qualified per-
sonnel.
- If the boiler is not going to be used for an
extended period of time, contact the
manufacturer’s Technical Assistance
Service to have at least the following ope-
rations performed:
• Switch the boiler OFF at the control
panel and at the mains power switch
• Close the boiler’s fuel cock, central
heating circuit shut-off cock and dome-
stic hot water circuit shut-off cock
• Empty the central heating circuit and
domestic hot water circuit if there is any
risk of freezing
- The boiler must be serviced at least once
a year. Servicing must be arranged in
advance with the manufacturer’s
Technical Assistance Service
Observe the following precautions to ensure
safe operation of the boiler.
aDo not allow children or uninformed per-
sons to operate the boiler.
aDo not operate any electrical devices or
equipment, including switches or dome-
stic appliances, etc., if you can smell
fuel or fumes. In the event of a gas leak,
thoroughly ventilate the room by opening
wide all doors and windows, close the
gas shut-off valve and call the manu-
facturer’s Technical Assistance Service
immediately to arrange urgent assistan-
ce by professionally qualified personnel.
aDo not touch the boiler while barefoot or
wet.
aNever clean the boiler without first
disconnecting it from the mains electri-
city supply by turning the mains power
switch and the control panel switch OFF.
aDo not tamper with or adjust the boiler’s
safety or control devices without prior
authorisation and instructions from the
manufacturer.
aDo not pull, disconnect, or twist the elec-
trical cables coming from the boiler even
if it is disconnected from the mains elec-
tricity supply.
aDo not obstruct or restrict vents in
the room where the boiler is installed.
Adequate ventilation is essential for cor-
rect combustion.
aDo not store containers of flammable
substances in the room where the boiler
is installed.
aDo not leave items of packaging within
the reach of children.

5
2 DESCRIPTION OF THE APPLIANCE
2.1
Description of the appliance
Novella boilers are gas fuelled boilers for
domestic heating.
They are equipped with an atmospheric bur-
ner and a cast iron primary heat exchanger.
They incorporate an open (type B11BS) com-
bustion chamber and are fitted with a hood
that ensures proper flue gas venting even with
a fluctuating flue draught.
They are also equipped with a flue gas
thermostat, as required by applicable safety
standards.
The burner is a stainless steel unit with stabili-
sed flame and smooth ignition.
The burner is fitted with an ionisation type
flame detection system.
The boiler’s control and safety devices con-
form to applicable technical and safety stan-
dards and are enclosed in a functional control
panel integrated in the body of the appliance.
Novella boilers use total shut-down logic
and do not waste energy because they only
start up when heat is actually needed by the
central heating system (i.e. when the room
thermostat trips).
Novella boilers can be connected to a storage
cylinder to produce domestic hot water, and
can be equipped with temperature controllers
in the form of specific accessories.
Installation, maintenance and access to inter-
nal components is facilitated by a large front
panel.
The key features of these boilers include:
- electronic ignition with ionisation flame
detection
- adjustable smooth ignition
- gas supply solenoid valve with built-in pres-
sure stabiliser and double shutter for burner
control
- domestic hot water temperature control
- water circuit temperature and pressure
gauge
- provision for room thermostat or timer.
Novella RAI PV models also feature:
- central heating circuit pump
- 12 litre expansion vessel
- 3 bar central heating circuit safety valve.
2.2
Optional accessories
- Wall-mounted weekly timer thermostat (part
number 1100279)
- Pump manifold kit (part number 694769)
- High head pump kit (part number 1100269)
- RO120 storage cylinder (part number
696339)
- Pump or valve controlled multizone central
heating kit with total shut-down function
(part number 696439)
- Lifting brackets (part number 696429)

INSTALLATION MANUAL
6
2.3
Main parts of the boiler
8
10
11
9
1
2
3
4
6
5
7
12
19
21
22
20
13
14
15
16
17
18
Fig. 2.2
Fig. 2.1
Novella 24 - 31 RAI PV boilers
Key
1 Control panel
2 Temperature sensor sockets
3 Boiler body
4
Electronic ignition and flame detection unit
5 CH pump
6 Water circuit drain cock
7 Ignition electrode
8 Flame detection sensor
9 Burner
10 Gas supply solenoid valve
11 Lifting points
12 Expansion vessel
Novella 24 - 31 - 45 RAI boilers
Key
13 Control panel
14 Temperature sensor sockets
15 Boiler body
16
Electronic ignition and flame detection unit
17 Ignition electrode
18 Water circuit drain cock
19 Flame detection sensor
20 Burner
21 Gas supply solenoid valve
22 Lifting points

7
2.4
Control panel
29 28
23 24 25 26 27
31 30 30
Fig. 2.3
Key
23 Main switch
24 Central heating temperature control
25
Water circuit temperature and pressure
gauge
26 Safety thermostat (manual reset)
27 Flue gas thermostat (manual reset)
28 Burner lockout LED warning light
29 Power on LED indicator
30 Quick reference guide
31 Burner reset button
2.5
Technical specifications
24 RAI
PV
24 RAI 31 RAI
PV
31 RAI 45 RAI
Rated heat input, CH kW 26,6 34,4 50,0
kcal/h 22880 29590 43000
Rated heat output, CH kW 24,0 31,0 45,0
kcal/h 20640 26660 38700
Electrical consumption W 103 15 103 15
Boiler class II 2H3+
Power supply voltage V ~ Hz 230 ~ 50
Index of protection IP 40
Losses from stack and casing with burner off % 1,65 1,37 1,23
Central heating circuit characteristics
Maximum pressure - temperature bar -°C 3 - 100
CH temperature setting range °C 34-82
Expansion vessel litres 12 -- 12 --
Gas pressure
Rated gas pressure, methane (G 20) mbar 20
Rated gas pressure, LPG (G31) (G 30 - G 31) mbar 28-30/37
Water connections
CH flow – return Ø3/4"
Gas inlet Ø1/2"
Emissions with G 20 gas
CO below p.p.m. 21 19
CO2 % 5,6 5,7 5,5
NOx (according to EN 297) Class 1
 FluegasΔt °C 93 96 113
Boiler dimensions
Height mm 850
Width mm 450 600
Depth mm 700 675 700 675 720
Weight of boiler kg 108 100 126 118 154

INSTALLATION MANUAL
8
2.6
Identification
Novella boilers are identified by a product
name plate giving the boiler’s serial number,
model and main technical and performance
data.
b It is essential to specify the correct
model of boiler when ordering spare
parts or requesting technical assistance.
If the name plate or any other means of
clearly identifying the product is defa-
ced, removed or lost, proper installation
and servicing may be rendered difficult.
GAS FUELLED BOILER
OBLIGATORY GROUND CONNECTION
Model
Code
Year
Heat input at
furnace (Qn/Hi)
Boiler water
capacity
Useful heat
output (Pn)
Heat exchanger
surface area
Maximum working
pressure (mwp)
Maximum admissible
temperature
Power supply Maximum current
draw
NOx class Maximum energy
consumption
Gas supply pressure
CLASS OF BOILER
TYPE OF BOILER
COUNTRY OF DESTINATION
Index of protection
PIN Code
Serial No.
PARAMETER 24 RAI 31 RAI 45 RAI
Lower Wobbe index (at 15°C-1013 mbar) G20 (MJ/m3) 45,5
(at 15°C-1013 mbar) G30 (MJ/m3) 80,9
(at 15°C-1013 mbar) G31 (MJ/m3) 70,9
Main burner
Number of nozzles 3 4 6
Nozzle diameter G20 Ø mm 2,40 2,40 2,40
G30 Ø mm 1,50 1,50 1,45
G31 Ø mm 1,50 1,50 1,45
Nozzle pressure (downstream from valve in central hea-
ting only mode)
G20 mbar Δp13,5 13,5 12,7
mm H2O Δp138 138 129
G30 mbar Δp28,4 28,0 27,8
mm H2O Δp289 285 283
G31 mbar Δp36,5 34,7 35,7
mm H2O Δp372 354 364
Maximum gas ow rate, CH (*) G20 m3/h 2,80 3,50 5,10
G30 kg/h 2,09 2,70 3,92
G31 kg/h 2,05 2,66 3,86
(*) Temperature 15°C; Pressure 1013 mbar.
Fig. 2.4

9
C
P
Fig. 2.5
2.7
Material supplied
The boiler is delivered in a wooden cage.
Proceed as follows to remove this.
- Remove the staples fixing the wooden cage
to the pallet.
- Lift off the wooden cage.
The following items are delivered in a plastic
bag inside the boiler:
- Operation manual
- Installation manual
- LPG conversion kit (nozzles, label, seals).
Instruction manuals are integral parts of the
boiler. On unpacking, locate the manuals and
keep them safe.
Fig. 2.6
MODEL
24 RAI 24 RAI PV 31 RAI 31 RAI PV 45 RAI
Net weight 100 108 118 126 154 kg
Gross weight 119 127 138 146 174 kg
2.8
Handling
Once you have removed the packaging, pro-
ceed as follows to handle the boiler.
- Remove the screws securing the boiler to
the wooden pallet.
- Remove the front panel (P) and top panel
(C) from the casing (fig. 2.6).
- Lift the boiler using two 3/4” pipes (1)
pushed through the lifting points (2) (fig.
2.7).
b Wear suitable personal protective
equipment and use suitable safety
devices.
aDo not leave items of packaging within
the reach of children.
2
1
Fig. 2.7

INSTALLATION MANUAL
10
2.9
Overall dimensions and water fittings
Fig. 2.8
Fig. 2.9
Novella 24, 31, 45 RAI boilers
Novella 24, 31 RAI PV boilers
DESCRIPTION MODEL
24 RAI 24 RAI PV 31 RAI 31 RAI PV 45 RAI
A 450 154 mm
B 675 700 675 700 720 mm

11
2.10
Water circuit
AB
MI
GAS
A
RI
B
C
D
E
F
G
MI
GAS
RI
A
B
C
D
A Water circuit drain cock
B Water circuit expansion vessel
C Water circuit safety valve
D CH circuit pump
E CH circuit temperature control sensor
F Water circuit temperature gauge
sensor
A Water circuit drain cock
B CH circuit temperature control sensor
C Water circuit temperature gauge
sensor
D Safety thermostat temperature sensor
G Safety thermostat temperature sensor
MI CH flow
RI CH return
AB Storage cylinder connection
GAS Gas supply
MI CH flow
RI CH return
GAS Gas supply
Fig. 2.10
Novella 24, 31, 45 RAI boilers
Novella 24, 31 RAI PV boilers
Fig. 2.11

INSTALLATION MANUAL
12
0
0,2
0,4
0,6
0,8
1
1,2
1,4
200400 600 800 1000 1200 1400 1600180020002200 2400 2600 2800
Novella 24, 31
Portata (l/h)
Perdite di carico (m.c.a.)
Nove lla 45
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
5
200400 600800 100012001400 1600 1800 2000 2200 2400
Speed ISpeed II
Speed III
Flow rate (l/h)
Useful head (m approx.)
Boiler’s water-side pressure drop
Novella RAI boilers come without a pump. A
pump must therefore be provided as part of
the installation. In order to choose a pump of
Useful head of pump
Novella RAI PV series boilers are pre-fitted
with a pump to which all water and electrical
connections have already been made. Pump
performance is illustrated by the curves in the
following graph.
the right size, bear in mind the boiler’s water-
side pressure drop, as shown in the following
graph.
The pump is configured in the factory to run at
maximum speed, i.e. speed III. Slower pump
speeds may nevertheless be set with low load
loss systems in order to reduce energy con-
sumption.
b On initial start-up and at least every year,
check that all the pumps in the system
rotate freely. Sludge and limescale can
build up and cause seizure, especially
after long periods of disuse.
aNever run the pump dry.
Fig. 2.12
Fig. 2.13
Fig. 2.14
Pressure drop (m approx.)
Flow rate (l/h)

13
2.11
Wiring diagram
IG Main switch FU Fuse LV Green “power on” LED indicator LR Red “burner lockout” LED warning light RS Burner reset button TR CH circuit temperature control TS Safety thermostat (manual reset) TF Flue gas thermostat (manual reset)
Fig. 2.15
PI CH pump AP Ignition and flame detection unit VG Gas supply solenoid valve EA Ignition electrode ER Flame detection sensor

INSTALLATION MANUAL
14
3 INSTALLATION
3.1
Installation standards
The boiler must be only be installed by qua-
lified personnel in conformity to the following
reference standards:
- UNI-CIG 7129
- UNI-CIG 7131
- IEC 64-8.
Installers must also ensure conformity to fire
prevention standards, gas safety standards
and local bylaws.
3.2
Place of installation
Novella RAI boilers must be installed in
rooms with vents that conform to applicable
technical standards and safety legislation.
aBoilers must be installed indoors. They
are not designed for outdoor use and
are not fitted with automatic frost protec-
tion devices.
IMPORTANT
Before installing the boiler, thoroughly flush
out all pipes to remove any dirt and deposits
that could compromise the correct functioning
of the boiler.
Install a water collector under the safety valve
and connect it to the nearest drain to evacua-
te any water coming out of the safety in the
event of overpressure. The domestic hot water
circuit does not require a safety valve but the
installer should nevertheless check that the
water supply pressure does not exceed 6 bar.
If necessary, install a pressure reducer.
Before lighting the burner for the first time,
make sure that the boiler is configured for
use with the type of gas supplied. The type
of gas is specified on the packaging label
and on the boiler’s own name plate.
Make sure that the flue is able to withstand
the temperature of the flue gases and that it
has been designed and made in conformity to
applicable standards. The flue must also be as
straight as possible, sealed, insulated and not
blocked or choked.
3.3
Installation in existing systems
Perform the following checks before installing
Novella boilers in existing systems.
- Check that the flue is large enough and
suitable for the characteristics of the boiler.
- Check that the characteristics of the boiler’s
pump (see the graph on page 12) are suita-
ble for the existing system. Existing pumps
are no longer needed.
- Make sure that the central heating circuit
has been flushed out to remove all sludge
and limescale, and that it has been properly
de-aerated.
- Make sure that the system is fitted with
safety and control devices that conform to
applicable legislation and standards.
- Check the hardness of the water supply
to ascertain whether a softening system is
required.
Refer to the following values.
REFERENCE VALUES
pH 6-8
Electrical conductivity less than 200 mV/cm (25°C)
Chlorine ions less than 50 ppm
Sulphuric acid ions less than 50 ppm
Total iron less than 0,3 ppm
Alkalinity M less than 50 ppm
Total hardness 35° F
Sulphur ions none
Ammonia ions none
Silicon ions less than 30 ppm

15
3.4
Water connections
MI
RI
AB
MI
RI
Novella boilers are designed and made for
use in central heating systems, but can also
be used to generate domestic hot water if
connected to a suitable storage cylinder.
The specifications of the water fittings are as
follows.
Novella 24, 31 RAI PV boilers
MI CH flow 3/4” M
RI CH return 3/4” M
AB Storage cylinder connection 3/4” M
Novella 24, 31 RAI boilers
MI CH flow 3/4” M
RI CH return 3/4” M
Novella 45 RAI boilers
MI CH flow 1” M
RI CH return 1” M
b The choice of system components and
the method of their installation are left
up to the heating engineer installing the
system. Installers must use their experti-
se to ensure proper installation and fun-
ctioning in conformity to all applicable
legislation.
b Circuits filled with anti-freeze must be fit-
ted with water disconnectors.
Fig. 3.1
Fig. 3.2
DESCRIPTION
MODEL
24 RAI 31 RAI 45 RAI
A 64 28 28 mm
Novella 24, 31, 45 RAI
Novella 24, 31 RAI PV
3.5
Electrical connections
Use a multi-pole disconnector with a contact
gap of at least 3 mm to connect the appliance
to the mains electricity supply. The appliance
functions on an alternating current supply
of 230 V, 50 Hz. Consumption is 150 W. The
appliance conforms to EN 60335-1 standard.
b The following instructions are mandatory.
- Install a multi-pole magnetic thermal
trip switch and disconnector confor-
ming to IEC-EN standards (with a con-
tact gap of at least 3 mm).
- Respect the polarity of the L1 (Phase) -
N (Neutral) connections.
- Use cables with insulation and cross
section conforming to applicable stan-
dards (minimum cross section 1.5
mm2).
- Always refer to the electrical wiring dia-
grams in this manual when performing
any electrical work.
- Ensure that an efficient ground connec-
tion is provided.
aIt is strictly forbidden to use fuel and/
or water pipes to ground the appliance.
The manufacturer declines all respon-
sibility for damage caused by failing to
ground the appliance adequately.

INSTALLATION MANUAL
16
Fig. 3.3
Fig. 3.4
Fig. 3.5
- Unscrew the two fixing screws and remove
the protective cover (A) from the casing
(fig. 3.3).
- The electrical connection terminals are
located underneath (fig. 3.3).
- Connect up the (optional) room thermostat
and/or timer as shown in the electrical
wiring diagrams in this manual.
- Connect up the electrical power supply (fig.
3.4).
- Connect up the room thermostat (TA) (fig.
3.5).
b If a room thermostat is connected, remo-
ve the bridge from terminals 4-5.
b The contacts of the room thermostat
must be able to function at a voltage of
230 V, 50 Hz.

17
3.6
Gas connections
daia Novella RAI boilers must be connected
to the methane or LPG gas supply in conformi-
ty to applicable standards (figs. 3.6 and 3.7).
Perform the following checks before making
the connection.
- Check that the boiler is compatible with the
type of gas supply.
- Check that the gas supply pipes are thorou-
ghly clean.
Fit a suitably sized filter in the gas supply pipe
if the gas supply contains any solid particles.
b The gas supply line must be suitable for
the flow rate demanded by the burner.
The gas supply must also be equipped
with all the necessary safety and control
devices required by applicable legisla-
tion and standards.
b On completion of the installation, check
that all joints are sealed in conformity to
the relevant installation standards.
3.7
Gas supply conversion
The boiler comes ready for use with methane
gas (G20), but can be converted to work with
LPG (G30/G31) using the conversion kit pro-
vided. Conversion must be performed by the
manufacturer’s Technical Assistance Service.
The boiler can be converted even after instal-
lation. To do so, proceed as follows.
REPLACING THE NOZZLES
- Remove the front panel from the casing.
- Unscrew the two nozzles from the methane
burner and replace them with the LPG noz-
zles provided in the kit, using the aluminium
seals also provided (fig. 3.8).
GAS
GAS
Fig. 3.6
Fig. 3.7
Fig. 3.8
DESCRIPTION
MODEL
24 RAI 31 RAI 45 RAI
A 50 28 36 mm
GAS - Gas supply
GAS - Gas supply

INSTALLATION MANUAL
18
DISABLING THE PRESSURE REGULATOR
For the boiler to work with LPG fuel, the pres-
sure regulator on the valve group needs to be
disabled. To do so, proceed as follows:
- Screw the pressure regulator screw (1) all
the way in (fig. 3.9).
- Unscrew the pressure measurement point
screw (A) about 3 turns and connect up the
pressure gauge (fig. 3.9).
SMOOTH IGNITION
- Turn the ignition adjuster screw (B) to obtain
the correct pressure for smooth ignition (fig.
3.10).
Start up the boiler as instructed on page 21.
NOZZLE PRESSURE
- Adjust the pressure regulator on the LPG
supply until the pressure gauge reads out
the value specified in the table below (fig.
3.11):
24 RAI 31 RAI 45 RAI
G30 G31 G30 G31 G30 G31
28,4 36,5 28,8 34,7 27,8 35,7
mbar
- Disconnect the pressure gauge and close
the pressure measurement point.
- Check the tightness of all the joints discon-
nected previously.
- Apply the LPG label supplied with the boiler
to the inside of the boiler casing (fig. 3.12).
- Remove any METHANE (G20) labels from
the outside and inside of the boiler casing
(fig. 3.12).
B
1
A
Country of destination:
Presión alimentación gas:
G20
G31
20 mbar
37 mbar
Regulación realizado por el fabricante:
G20 - 20 mbar - 2H METANO
ATENCIÓN
Leer cuidadosamente el manual de
instrucciones antes de la instalación y
puesta en servicio de la caldera.
0694
II2H3P
C13,C33,C43,C53,C63Tipo de aparato
Categoría del aparato
:
:
_ _
Boiler configured for:
Country of destination: ....
G30+G32 28-30/37 mbar L.P.G.
Fig. 3.11
Fig. 3.10
Fig. 3.9
Fig. 3.12

19
RI
3.8
Flue gas vent and air intake
Flues and stack connections must be made in
conformity to all applicable local and national
laws and standards. The use of rigid pipes is
mandatory.
All joints between pipe sections must be her-
metically sealed and all parts of the flue must
be resistant to high temperatures, condensate
and mechanical stress.
b Novella boilers are equipped with a flue
gas thermostat, located inside the hood.
This thermostat shuts down the boi-
ler immediately in the event of flue gas
blowback.
b Uninsulated flue pipes are potentially
dangerous and can cause burns.
Fig. 3.13
DESCRIPTION MODEL
24 RAI 31 RAI 45 RAI
B 72 77 97 mm
ØI 132 142 182 Ømm
3.9
Filling the water circuit
Novella RAI boilers must be fitted with a
water circuit filling system connected to the
central heating return line (fig. 3.14).
- Make sure that the boiler drain cock is
closed before attempting to fill the boiler
(fig. 3.5)
- Open the water circuit shut-off cocks and
slowly fill the circuit until the pressure gauge
reads out a value of 1.5 bar (cold)
- Close the water circuit shut-off cocks(fig.
3.16).
RI
Fig. 3.14
Fig. 3.15
Fig. 3.16

INSTALLATION MANUAL
20
3.10
Emptying the water circuit
- Turn the electricity supply off by switching
the boiler’s mains power switch and con-
trol panel switch OFF (0) before starting to
empty the boiler (fig. 3.17).
- Make sure that the water circuit shut-off
cocks are closed.
- Connect a rubber hose to the hose union on
the boiler’s drain cock and open the cock
(fig. 3.18).
ON
OFF
Fig. 3.17
Fig. 3.18