Centrometal CentroPlus 25 Owner's manual

CentroPlus
TECHNICAL INSTRUCTIONS
HEATING TECHNIQUE
Centrometal d.o.o. - Glavna 12, 40306 Macinec, Croatia, tel: [phone], fax: [phone]
for installation, use and maintenance
of hot water boiler
and installation of additional equipment
TU-CP-1-2022-ENG
ENG

TECHNICAL DATA
Technical data
Boiler
dimensions
with casing
Lenght
Width
Height
(A)
(B)
(C)
TYPE
CentroPlus 25
wood pellets oil
Fuel size
(mm)
25
15-25
1
205
160
0,029
0,030
10
2
solid fuel
12-20
79
320x220
561x600x420
141
underpressure
25
7,4-25
-
115
95
0,012
0,007
10
-
EL oil
-
-
-
571x320x378
69
overpressure
Flow and return line (outer thread)
Filling/drainage (internal thread)
Heat exchanger connector (outer thread)
Connector of exchanger sensor(internal thread)
max.
500x150x150 f6 x max.50 -
Nominal heat output
Heat output range
Boiler class
Required chimney underpressure
Water amount in boiler
Exhaust gas temperature at nominal heat output
Exhaust gas temperature at minimum heat output
Exhaust mass flow at nominal heat output
Exhaust mass flow at minimum heat output
Standby heat losses
Boiler resistance on water side at nominal output
Combustion period at nominal output
Fuel type
Maximum heat input
Fuel moisture content
Firebox volume/tank volume
Wood feeding opening AxB
Combustion chamber dimensions
Combustion chamber volume
Combustion chamber type
Required minimum accumulation next to boiler
Electrical power input
Temp. and press. of water from water supply line
into heat exchanger
Supply voltage
Frequency
Current type
Boiler body mass
Total mass - (boiler with casing and accessories)
Max. operating overpressure
Max. operating temperature
Flue gas tube – external diameter
25
7,5-25
3
17
155
170
95
0,015
0,005
10
34
wood pellets
max. 12
330
-
571x320x378
69
overpressure
by EN 303-5 point 4.2.5
250
230
50
~
1070
915
1260
419
464
2,5
90
150
5/4”
1/2”
3/4”
1/2”
Boiler
connections
(kW)
(kW)
(Pa)
(l)
(°C)
(°C)
(kg/s)
(kg/s)
(kW)
(mbar)
(h)
(kW)
(%)
(l)
(mm)
(mm)
(l)
(l/kW)
(W)
(V~)
(Hz)
(mm)
(mm)
(mm)
(kg)
(kg)
(bar)
(°C)
(mm)
(R)
(R)
(R)
(R)
Total system dimensions
Total length
Total width
Total height
(D)
(E)
(F)
1350
915
1365
Solid / Pellets
25 kW
Solid / Oil
25 kW
(mm)
(mm)
(mm)
1350
1545
1610
Solid
25 kW
1070
915
1260
2Technical instructions CentroPlus
(C°/bar) 10-15 °C, 2 bar

Boiler
dimensions
with casing
Lenght
Width
Height
(A)
(B)
(C)
TYPE
CentroPlus 35
wood pellets oil
Fuel size
(mm)
35
25-35
1
240
195
0,03
0,032
15
2
solid fuel
12-20
104
420x220
571x600x420
143
underpressure
35
10-35
-
135
105
0,017
0,01
15
-
EL oil
-
-
-
571x320x380
70
overpressure
Flow and return line (outer thread)
Filling/drainage (internal thread)
Heat exchanger connector (outer thread)
Connector of exchanger sensor(internal thread)
max.
500x150x150 f6 x max.50 -
Nominal heat output
Heat output range
Boiler class
Required chimney underpressure
Water amount in boiler
Exhaust gas temperature at nominal heat output
Exhaust gas temperature at minimum heat output
Exhaust mass flow at nominal heat output
Exhaust mass flow at minimum heat output
Standby heat losses
Boiler resistance on water side at nominal output
Combustion period at nominal output
Fuel type
Maximum heat input
Fuel moisture content
Firebox volume/tank volume
Wood feeding opening AxB
Combustion chamber dimensions
Combustion chamber volume
Combustion chamber type
Required minimum accumulation next to boiler
Electrical power input
Temp. and press. of water from water supply line
into heat exchanger
Supply voltage
Frequency
Current type
Boiler body mass
Total mass - (boiler with casing and accessories)
Max. operating overpressure
Max. operating temperature
Flue gas tube – external diameter
(kW)
(kW)
(Pa)
(l)
(°C)
(°C)
(kg/s)
(kg/s)
(mbar)
(h)
(%)
(l)
(mm)
(mm)
(l)
(l/kW)
(W)
(V~)
(Hz)
(mm)
(mm)
(mm)
(kg)
(kg)
(bar)
(°C)
(mm)
(R)
(R)
(R)
(R)
35
10,5-35
3
19
172
160
85
0,018
0,007
15
24
wood pellets
max. 12
330
-
571x320x380
70
overpressure
by EN 303-5 point 4.2.5
250
230
50
~
1070
1015
1260
476
522
2,5
90
160
5/4”
1/2”
3/4”
1/2”
Boiler
connections
Total system dimensions
Total length
Total width
Total height
(D)
(E)
(F)
1350
1015
1365
Solid / Pellets
35 kW
Solid / Oil
35 kW
(mm)
(mm)
(mm)
1350
1650
1610
Solid
35 kW
1070
1015
1260
3
Technical instructions CentroPlus
Technical data
(C°/bar) 10-15 °C, 2 bar

Boiler
dimensions
with casing
Lenght
Width
Height
(A)
(B)
(C)
TYPE
CentroPlus 50
wood pellets oil
Fuel size
(mm)
49
35-49
1
225
160
0,034
0,04
25
2
solid fuel
12-20
104
470x217
671x620x450
187
underpressure
49
14-49
-
178
113
0,024
0,014
15
-
EL oil
-
-
-
600x340x380
77
overpressure
Flow and return line (outer thread)
Filling/drainage (internal thread)
Heat exchanger connector (outer thread)
Connector of exchanger sensor(internal thread)
max.
500x150x150 f6 x max.50 -
Nominal heat output
Heat output range
Boiler class
Required chimney underpressure
Water amount in boiler
Exhaust gas temperature at nominal heat output
Exhaust gas temperature at minimum heat output
Exhaust mass flow at nominal heat output
Exhaust mass flow at minimum heat output
Standby heat losses
Boiler resistance on water side at nominal output
Combustion period at nominal output
Fuel type
Maximum heat input
Fuel moisture content
Firebox volume /tank volume
Wood feeding opening AxB
Combustion chamber dimensions
Combustion chamber volume
Combustion chamber type
Required minimum accumulation next to boiler
Electrical power input
Temp. and press. of water from water supply line
into heat exchanger
Supply voltage
Frequency
Current type
Boiler body mass
Total mass - (boiler with casing and accessories)
Max. operating overpressure
Max. operating temperature
Flue gas tube – external diameter
(kW)
(kW)
(Pa)
(l)
(°C)
(°C)
(kg/s)
(kg/s)
(mbar)
(h)
(%)
(l)
(mm)
(mm)
(l)
(l/kW)
(W)
(V~)
(Hz)
(mm)
(mm)
(mm)
(kg)
(kg)
(bar)
(°C)
(mm)
(R)
(R)
(R)
(R)
49
14-49
3
22
220
180
150
0,025
0,01
25
16
wood pellets
max. 12
330
-
600x340x380
77
overpressure
by EN 303-5 point 4.2.5
250
230
50
~
1140
1145
1260
580
630
2,5
90
180
5/4”
1/2”
1”
1/2”
Boiler
connections
Total system dimensions
Total length
Total width
Total height
(D)
(E)
(F)
1420
1145
1365
Solid / Pellets
49 kW
Solid / Oil
49 kW
(mm)
(mm)
(mm)
1420
1775
1610
Solid
49 kW
1140
1145
1260
4
Technical data
Technical instructions CentroPlus
(C°/bar) 10-15 °C, 2 bar

Solid fuel
PVL
B=E
DVD
A=D
TU
ZO
PVV
ZK
ZP
PVL
PD
TP
DP
CentroPlus 25/35
DP
ZO
PVV
TO
PVL
CentroPlus 50
TO
DP
ZO
PVV
PVL
DP
TO
PVL
DP
CentroPlus 25/35 CentroPlus 50
TO
PD
PD PD
PD
SP
CE
ZA
GR
ZP
ZP
ZK
ZK
TP
C=F
Note: depending on the order, the boiler can be also delivered as left version.
5
Technical data
Technical instructions CentroPlus

TEHNIKA GRIJANJA
B=E
F
RP
UR
GV
DV
GO
OG
PU
Solid fuel / EL fuel oil
DVD
°c
011
0
°c
TM
TU
DP
ZO
PVV
ZK
ZP
PVL
PD
A
D
TP
CentroPlus 25/35
PR
DP
ZO
PVV
TO
CentroPlus 50
PR
DP
ZO
PVV
TO
CentroPlus 25/35 CentroPlus 50
CE
ZA
GR
SP
ZP
ZP
ZK
ZK
DP TO
PVL
PD
PD
PU
°c
011
0
°c
DP TO
PVL
PD
PD
PU
°c
011
0
°c
TP
Note: depending on the order, the boiler can be also delivered as left version.
C
6
Technical data
Technical instructions CentroPlus

TEHNIKA GRIJANJA
B
E
C
RP
PR PS
GV
DV
GO
DVD
OG
F
TM
MS
0
1
08:42
OFF
A
D
TU
DP
ZO
PT
PP
PC
PVV
ZK
ZP
PVL
PD
TP
CentroPlus 25/35
PR
PS
DP
ZO
PVV
TO
CentroPlus 50
PS PR
DP
ZO
PVV
TO
Solid fuel / wooden pellets
CentroPlus 25/35 CentroPlus 50 CE
ZA
GR
SP
ZP
ZP
ZK
ZK
TP
DP TO
PVL
PS
PD PD
PP
PC
0
1
08:42
OFF
DP TO
PVL
PS
PD PD
PP
PC
0
1
08:42
OFF
Note: depending on the order, the boiler can be also delivered as left version.
DESCRIPTION OF BOILER SYMBOLS FOR SOLID FUEL, SOLID FUEL / EL FUEL OIL, SOLID FUEL / WOODEN PELLETS
LEGEND:
CE - cleaning brush
DP - chimney connection
DV - left firebox lower door
DVD - right firebox lower door
GO - right firebox upper door
GR - scraper
GV - left firebox upper door
MS - micro switch
OG - opening for monitoring
PC - plastic flexible tube
PD - connection for flue gas measurement
PP - pellet burner CPPL
PR - pellet control unit CPREG
PS - pellet tank CPSP
PT - pellet feeder CPPT
PU - oil burner
PVL - inlet line
PVV - outlet line
RP - draft controller (such as CALEFFI 543 or ESBE ATA200)
SP - blind plate
TM - thermometer
TO - thermal protection connectors
TP - pump thermostat
TU - sensor sleeve
UR - oil-control unit EKO-CK/CKB
ZA - poker
ZK - back ash box holder
ZO - cleaning opening
ZP - back ash box
7
Technical data
Technical instructions CentroPlus

1.0. GENERAL
The hot water boiler CentroPlus has a modern design and construction. It is made out of controlled
high-quality materials, welded with the most modern technology and meets all special requirements for
connection to the central heating system.
1.1. BOILER DESCRIPTION
Steel hot water boiler CentroPlus has two separate combustion chambers inside the common boiler's
water chamber. The left combustion chamber is intended for firing with solid or liquid fuel. It has a large
heating area and small resistance, and large door which enables simple heating with big-size fuel. The
right combustion chamber is intended for firing with wooden pellets or liquid fuel and it is characterised
by 3-passes flue gas system with turbolators and large heating area which provides high boiler
efficiency. A large amount of water in the boiler enables longer pellet burner work (in that way it is
reduced the number of switching on the burner and extends the burner life time). The boiler cleaning is
very simply and can be done from the front or back side. Depending on the installed additional
equipment, there are three models of boiler use:
- solid fuel firing,
- solid fuel and wooden pellets firing,
- solid fuel and EL fuel oil firing.
The boiler is supplied without above mentioned additional equipment, which can be additionaly
ordered. The additional equipment is delivered in a separate packing and it is installed onto the boiler
after the boiler is istalled into the boiler room and connected to the central heating system.
1.2. DELIVERY OF THE BOILER CentroPlus
Due to easier transport and positioning into the boiler room, the boiler CentroPlus is not delivered with
built-in thermal insulation and casing (it is delivered separately):
- the boiler body with boiler door is delivered on a wooden pallet (with lid of the left firebox door,
lid of the right firebox register, ashtrays, left and right firebox grates and turbulators);
- the cardboard box with boiler casing, thermal insulation, themometer, draft controller ( such
as CALEFFI 543 or ESBE ATA200), back ash box, cleaning accessories (accessories holder,
brush, scraper and poker), protective box for extension for the pellet burner and set of screws
and bolts.
1.3. OBLIGATORY ADDITIONAL EQUIPMENT FOR THE BOILER CentroPlus
WHICH IS INSTALLED TO CLOSED CENTRAL HEATING SYSTEM
CentroPlus 25/35:
- thermal valve (such as CALEFFI 543) -1 piece
CentroPlus 50:
- thermal valve (such as CALEFFI 543) -2 pieces
- thermal protection exchanger Centrometal - 2 pieces
8
General, boiler delivery, additional equipment
Technical instructions CentroPlus

1.4. ADDITIONAL EQUIPMENT FOR THE BOILER CentroPlus 25/35
Depending on preferred boiler use it is necessary to install appropriate additional equipment to the
boiler:
1) Additional equipment for solid fuel / wooden pellet firing:
- pellet burner CPPL-35, digital boiler control unit CPREG for pellet burner CPPL-35;
- pellet tank CPSP;
- pellet feeder CPPT 14-35.
2) Additional equipment for solid fuel / EL fuel oil firing:
- boiler control unit EKO-CK/CKB for the oil burner;
- oil burner with appertaining equipment.
1.5. ADDITIONAL EQUIPMENT FOR THE BOILER CentroPlus 50
Depending on preferred boiler use it is necessary to install appropriate additional equipment to the
boiler:
1) Additional equipment for solid fuel / wooden pellet firing:
- pellet burner CPPL- 50, digital boiler control unit CPREG for pellet burner CPPL-50;
- pellet tank CPSP;
- pellet feeder CPPT 40/50.
2) Additional equipment for solid fuel / EL fuel oil firing:
- boiler control EKO-CK/CKB for the oil burner;
- oil burner with appertaining equipment.
2.0. POSITIONING AND ASSEMBLY OF THE BOILER/ADDITIONAL EQUIPMENT
The boiler body is delivered on a wooden pallet on which it is fixed with four holders. Before placing the
boiler body into the boiler room, it should be removed from pallet (Figure 1.). The boiler positioning,
assemble and installation of the additional equipment must be performed by a qualified person. We
recommend to place the boiler on a concrete base which is 50 to 100 mm higher than floor. The boiler
room has to be frost-resistant and ventilated. The boiler has to be placed in a way which enables
connection to the chimney (see point 4.0) and supervising the boiler and additional equipment,
cleaning and maintenance (see Figure 4a.). The boiler casing assemble has to be done in accordance
with the instructions (Figure 2.).
Figure 1. The boiler removing from the wooden pallet
Front side of the
boiler body
Backside of the
boiler body
Boiler leg
Wooden pallet
Wood screw
Wood screw
Front side of
the boiler body Backside of the
boiler body
Boiler leg
Wooden pallet
Boiler CentroPlus
Holder
Holder
9
Additional boiler equipment, positioning and assembly
Technical instructions CentroPlus

2.1. SOLID FUEL FIRED BOILER (EQUIPMENT FOR WOODEN PELLETS AND
OIL IS NOT BUILT-IN YET)
Draft controller has to be installed to the boiler left side (such as CALEFFI 543, ESBE ATA200) and
connect it by a chain to the movable lid on the boiler lower door. The electrical connector and heating
pump connect according to the electrical scheme (Scheme 5.).
2.2. SOLID FUEL/WOODEN PELLETS FIRED BOILER
To the left boiler side install draft controller (such as CALEFFI 543, ESBE ATA200) and connect it by a
chain to the movable lid on the boiler lower door. The pellet burner CPPL install onto the right lower
door. The pellet control unit CPREG install to the casing cover. Above the right lower door (on the
casing) install the microswitch. Place the pellet tank CPSP with the pellet feeder CPPT next to the
boiler, to its right side. Detailed desctiption of pellet equipment is described in “Technical instructions
for startup and setting of the Cm Pellet-set for the CentroPlus and CentroPlus-B boilers (solid fuel and
wooden pellets fired)” and in “Technical instructions for pellet tank and screw feeder which are
delivered with equipment for wooden pellet firing.”
2.3. SOLID FUEL / EL OIL FUEL FIRED BOILER
To the left boiler side install draft controller (such as CALEFFI 543, ESBE ATA200) and connect it by a
chain to the movable lid on the boiler lower door. Remove the blind plate from the lower right door from
the ceramic exstension for the oil burner. The oil burner has to be installed to the plate opening with
ceramic and connected to the fuel supply. Install the boiler control unit EKO-CK/CKB for oil burner to
the casing cover and connect it to the burner, electical connection and heating pump according to the
electrical scheme 6.
Scheme installation of oil burner to the boiler
Screw holes Fire tube hole
Right boiler
lower door
45°
105
150
M10
4 holes
2.3.1. THE OIL BURNER INSTALLATION TO THE BOILER
10
Boiler positioning and assembly
Technical instructions CentroPlus

Figure 2. Installation of the casing to the boiler
1
23
4
5
6
7
9
10
Bracket X
(the boiler front
side)
Middle bracket
(the boiler front
side)
0
1
08:42
OFF 11
Bracket Y
(the boiler back
side)
13
3,9x9,5
(3x)
12
4,2x32
4,2x32
4,2x32
(3x)
4,2x32
(4x)
M6x10
(2x)
- Remove protective film from the boiler body.
- Place side 1 on two middle brackets and tighten it by two M6 x 10 mm screws.
- Place side 2 into grooves on side 1 and put it onto left lower bracket X .
- Place side 3 into grooves on side 1 and put it onto right lower bracket X .
- Put the side 9 on side 1 and to left and right upper bracket X .
- Place the lateral left side 4 on two back left brackets Y and then put it on two front left brackets X so that side
2 and side 9 are linked.
-Tighten the side 9 and the side 4 to the boiler body using screw 4,2 x 32 in a way from boiler toward casing
(Detail 1).
- Place the lateral right side 5 on two back right brackets Y and then put in two front right brackets X so that
side 3 and side 9 are linked.
- Tighten the side 9 and the side 5 to the boiler body using screw 4,2 x 32 in a way from boiler toward casing
(Detail 1).
- Place the side 6 to flue gas chamber and push it and hook into grooves on the lateral sides 4 and 5 .
- Tighten the side 8 to the lateral left side 4 and lateral right side 5 using four screws 4,2 x 32mm so that side 6
is also tightened.
- Put the side 7 on back middle bracket and tighten it onto the lateral left sides 4 and side 6 using three screws
4,2 x 32 mm.
- Put the cover 10 onto the boiler.
- Pull the control sensors through opening on the cover 10 (pellet control unit CPREG or boiler control unit
EKO-CK/CKB are parts of the additional equipment if it has been purchased (if it is not, skip this step and next
step of the installation) and push it into the sensor sleeve from the the boiler upper side.
- Tighten to half (not completely) sheet metal screws 4,2 x 15 mm in the prepared holes on the casing cover 10
and put the boiler control unit 11 so that it is atached onto the screws.
- Tighten the protective sheet 12 onto the side 9 using three screws 3,9 x 9,5 mm.
- Drill two holes on the lateral left side 4 and tighten the bracket for cleaning accessories 13 onto the lateral left
side 4 using two screws 3,9 x 9,5 mm.
- Place the back ash box 14 on the back boiler side below the flue gas chamber onto prepared brackets using
two snaps (see page 7, positions ZP and ZK) which have to be adjusted so that box adhere well.
Detail 1. side 5
side 9
boiler body
screw 4,2x32
14
holders
8
11
Installation of casing
Technical instructions CentroPlus

3.0. OPENING FOR FRESH AIR
Each boiler room must have an opening for fresh air supply which is dimensioned in accordance with
boiler output (minimum opening area according to the below shown formula). The opening must be
protected with a net or a grate. All installation works must be performed in accordance with valid
national and European standards. The boiler must not operate in flammable and explosive
environment.
Q - boiler output in kW
2
A - opening area in cm
A = 6,02 Q
4.0. CONNECTION TO THE CHIMNEY
Properly dimensioned and built chimney is a precondition for safe boiler operation and heating
efficiency. A chimney must be thermally insulated, gas-tight and smooth. Cleaning door must be placed
in the lower part of a chimney. Walled chimney must be 3 layered with the middle mineral wool
insulation layer. The thickness of the thermal insulation has to be at least 30 mm if the chimney is built
against to interior wall and at least 50 mm if it is built on the outer side. Inner dimensions of the
chimney light diameter are dependent on the chimney height and boiler output, so they must be
chosen in accordance with diagram shown in Figure 4. The chimney usable height is the measure
from connection spot of smoke tube to the chimney top. As these boilers can be fired also with solid
fuel, chimney has to be chosen in accordance with diagram for solid fuel. The flue gas temperature on
the chimney exit has to be at least 30°C higher than the condensation temperature of combustion flue
gases. Selection and building of a chimney must be done by qualified person. Required maximum
distance from the boiler to the chimney has to be 1000 mm (minimum distance has to be 500 mm). A
flue gas tube has to be mounted under an inclination (at least 5°) and has to be tilted from the chimney
to the boiler (Figure 3.). A flue gas tube has to be mounted 10 mm deeper into the chimney in order to
prevent entering condensate into the boiler. The connecting flue gas tube, between the chimney and
the boiler, must be thermal insulated with mineral wool insulation which is 30-50 mm thick.
All works must be done in accordance with valid national and European standards.
Figure 3. Possible ways of connection boiler CentroPlus to the chimney
min. 500 mm
max. 1000 mm
10mm Opening for cleaning
Thermal insulation
Opening for cleaning
Thermal insulation
RECOMMENDATION
12
Opening for fresh air, connection to the chimney
Technical instructions CentroPlus

Figure 4. Chimney dimensioning for the boiler CentroPlus
Useful chimney height (m)
Boiler nominal output (kW)
5 10 15
Light chimney diameter (cm)
10
15
20
25
30
35
40
45
50
60
6 7 8 9
20
22
2530
18
An example of a chimney selection:
- Boiler heat output: 50 kW
- Fuel: Wood, wooden pellets, EL fuel oil
- Required usable chimney height: H = 8 m
- Required light chimney diameter: 25 cm
- Useful chimney height - chimney height
from connection spot of smoke tube to the
chimney top.
- Light chimney diameter - inner chimney
diameter.
5.0. THE BOILER INSTALLATION TO THE CENTRAL HEATING SYSTEM
All installation works must be done in accordance with valid national and European standards. The
boiler CentroPlus can be installed to the closed or open central heating system. In both cases the boiler
can be fired with solid fuel, wooden pellets or EL fuel oil. Installation has to be done in accordance with
Technical standards and by qualified person who will be responsilble for proper boiler operation.
Before the boiler is connected to the central heating system it is necessary to flush the system to
remove impurities that may remain after system installation. These works prevent boiler overheating,
noise in the system, disturbances at pump and mixing valve. The boiler connection to the central
heating system must be performed by holenders (never by welding). Safe distances which are required
for cleaning and maintenance are shown in Figure 4a.
Figure 4a. The minimal distance from the room walls min. 500 mm
max. 1000 mm
min. 1500 mm
13
Connection to the chimney, installation to the central heating system
Technical instructions CentroPlus

5.1. BOILER INSTALLATION TO THE CLOSED HEATING SYSTEM
In the closed heating system (an example that is shown in Scheme 1a and 1b) it is obligatory to install
certified safety valve with opening pressure of 2,5 bar, minimum seat diameter of 15 mm, minimum inlet
connection of 1/2", minimum exit connection of 3/4" and a membrane expansion vessel. Safety valve
and exspansion vessel have to be installed in accordance with professional rules and there must not be
any stop element between safety valve and the boiler (i.e. between expansion vessel and the boiler). In
all boiler types it is obligatory to connect the pump in accordance with electric diagram relevant for
specific boiler use (see point 7 in these instructions) so the heating pump switching on and off will be
dependent on the water temperature in the boiler. If the boiler is connected to the heating system as
shown in Scheme 1b., it is recommended to regulate the temperature in room with manual 4-ways
mixing valve.
Scheme 1a. An example of installation of the accumulation tank into the central heating
system required according to the EN 303-5 norm
- Obligatory installation of air self-
venting group (safety valve 2,5 bar)
Installation of the boiler CentroPlus to the closed heating system
(solid fuel/wooden pellets firing is presented, installation for the other types is the same)
Scheme 1b. An example of installation the
accumulation tank into the central heating
system when it is not required according
to the EN 303-5 norm
1
5
3
TEHNIKA GRIJANJA
bar
0
1
08:42
OF F
1
3
7
- Room thermostat
4
- Manual 3-ways mixing valve
- Thermometer
2
2
5
- Thermostat valve - ensures
boiler return temperature
at least 60°C
- Thermal protection of the boiler
6
7
- Manual 4-ways mixing valve
8
8
- Accumulation tank (CAS)
9
9
- Closed-type expansion vessel
bar
4
1 T
6
9
TEHNIKA GRIJANJA
0
1
08:42
OF F
14
Boiler installation to the closed heating system
Technical instructions CentroPlus

5.1.1. THE BOILER THERMAL PROTECTION - CentroPlus 25 / 35
According to the European EN standards it is obligatory to install the boiler thermal protection in
closed heating system. Boiler is factory prepared for boiler thermal protection installation. The heat
exchanger is factory installed into the boiler and the thermal safety valve 2 has to be installed as
shown in Scheme 2. In case of any damage of the boiler which is installed to the closed heating system
due its overheating, and if boiler and system are not equipped with thermal protection or if it is not
properly installed, guarantee will not be applied.
IMPORTANT:
Thermal protection must be connected to the water supply installation of the premises supplied from
the water supply line and not from hydrophor. In case of failure of power supply, boiler could be
overheated, and then hydrophor is not able to ensure required water supply.
THERMAL FUSE:
Thermal fuse for the boiler CentroPlus consists of a heat exchanger which is factory built in the boiler,
and thermal valve 2 (such as CALEFFI 543 513) (see Scheme 2.).
Part 2 installation has to be performed to the prepared connector (outer thread 3/4") on the upper part
of the boiler back side.
INSTALLATION (according to the Scheme 2.)
- the thermal valve installation 2 it is performed to the prepared connector (outer thread 3/4") 6
- connector 5 (internal thread 3/4") of the thermal valve connect to the thermal exchanger connector
which is fabric installed into the boiler 6 (outer thread 3/4")
- connector 4 (internal thread 3/4") of the thermal valve connect to the supply of the cold domestic
water
- the thermal exchanger connector 7 connect into the sawage
- into the coupling 1 (internal thread 1/2") twist the thermal valve sensor (outer thread 1/2").
bar
7
6
3
FROM THE
PUBLIC MAIN
WATER
DISTRIBUTION
LINE
2
3
Scheme 2. The thermal protection installation to the boiler CentroPlus 25/30 that is
installed to the closed heating system Safety valve 2,5 bar
12
54
SAWAGE
Central heating system
inlet
Central heating
system return
* Position of the thermal valve after installation
(valve head has to be down)
15
Boiler thermal protection
Technical instructions CentroPlus

5.1.2. THE BOILER THERMAL PROTECTION - CentroPlus 50
The boiler is factory prepared for installation of thermal protection ( two heat exchangers 1 and two
thermal valves 2 (such as CALEFFI 543) (see Scheme 2.1.). In case of any damage of the boiler
which is installed to the closed heating system due its overheating, and if boiler and system are not
equipped with thermal protection or if it is not properly installed, guarantee will not be applied.
IMPORTANT:
Thermal protection must be connected to the water supply installation of the premises supplied from
the water supply line and not from hydrophor. In case of failure of power supply, boiler could be
overheated, and then hydrophor is not able to ensure required water supply.
THERMAL FUSE
Thermal fuse for the boiler CentroPlus consists of two heat exchangers 1 and two thermal valves
2 (such as CALEFFI 543) (see Scheme 2.1.)
Installation of the parts 1 and 2 has to be performed to the prepared connector (internal thread 1" and
1/2'') at the upper part of the back boiler side.
INSTALLATION (according to the Scheme 2.1)
- into the larger coupling (internal thread 1") twist the heat exchanger, so it seal
- into the smaller coupling (internal thread 1/2") twist the thermal valve sensor 3 (outer thread 1/2")
(such as CALEFFI 543).
- the thermal valve connector 5 (internal thread 3/4") connect to the heat exchanger connector 6
(outer thread 1/2") and the thermal valve connector 4 (internal thread 3/4") connect to the supply of
the cold domestic water (public main water distribution line).
- the heat exchanger connector 7 (outer thread 1/2") connect into the sawage.
bar
3
2
FROM THE
PUBLIC MAIN
WATER
DISTRIBUTION
LINE
1
2
3
Scheme 2.1. The thermal protection installation to the boiler CentroPlus 50 that is
installed to the closed heating system
321
5
4
* Position of the thermal valve after installation
(valve head has to be down)
7
6
1
SAWAGE
SAWAGE
Central heating system
inlet
Central heating
system return
16
Boiler thermal protection
Technical instructions CentroPlus

5.2. THE BOILER INSTALLATION TO THE OPEN HEATING SYSTEM
If the boiler is installed to an open heating system, it is recommended to set the system according to the
Scheme 3a or 3b. In open heating system it is necessary to place the open expansion vessel to the
higher position than the highest heating body is placed. If the open expansion vessel is placed into the
unheated room, it is necessary to isolate it.
Scheme 3b. An example of installation of the accumulation tank to the central heating
system when it is not required according to the EN 303-5 norm
to the boiler
room
OPC
1
9
ABOVE THE HIGHEST HEATING BODY
4
2
Scheme 3a. An example of installation of the accumulation tank to the central heating
system required according to the EN 303-5 norm
An example of installation the boiler CentroPlus 25/35 to the open heating system
(solid fuel/wooden pellets firing is presented, installation for the other types is the same)
5
8 3
7
1
2
3
4
5
- CentroPlus 25/35 boiler
- tightly close
- manual 3-ways mixing valve
- manual 4-ways mixing valve
6
8
7
9
- thermostat valve- ensures the return line
temperature at least 60°C
- accumulation tank (CAS)
- room thermostat
- open expansion vessel OPC
OPC
9
2
ABOVE THE HIGHEST HEATING BODY
T
6
- thermometer
1
to the boiler
room
Boiler installation to the open heating system
17
Technical instructions CentroPlus

Scheme 4b. An example of installation of the accumulation tank to the central heating
system when it is not required according to the EN 303-5 norm
to the boiler
room
OPC
1
9
ABOVE THE HIGHEST HEATING BODY
4
2
Scheme 4a. An example of installation of the accumulation tank to the central heating
system required according to the EN 303-5 norm
An exaple of installation the boiler CentroPlus 50 to the open heating system
(solid fuel/wooden pellets firing is presented, installation for the other types is the same)
5
8 3
7
1
2
3
4
5
- CentroPlus 50 boiler
- tightly close
- manual 3-ways mixing valve
- manual 4-ways mixing valve
6
8
7
9
- thermostat valve- ensures the return line
temperature at least 60°C
- acumulation tank (CAS)
- room thermostat
- open expansion vessel OPC
OPC
9
ABOVE THE HIGHEST HEATING BODY
T
6
- thermometer
1
to the boiler
room
2
18 Technical instructions CentroPlus
Boiler installation to the open heating system

6.0. THE BOILER TEMPERATURE REGULATION
6.1. SOLID FUEL FIRING (EQUIPMENT FOR WOODEN PELLETS OR OIL IS
NOT INSTALLED)
The draft controller (such as CALEFFI 543, ESBE ATA200) is needed for the boiler temperature
regulation, and it has to be is installed on the boiler front left side (see page 5.). The draft controller
chain has to be adjusted in a way that boiler temperature do not exceed the temperature from 85 to
90°C by normal firing (opening for air is completely closed), and not drop under 65°C. It is necessary to
connect the pump of the heating system and domestic water by the socket placed at the boiler back
side ( the socket is connected to the pump thermostat).
6.2. THE BOILER FIRED WITH SOLID FUEL AND WOODEN PELLETS
The pump of the heating system and domestic water is necessary to connect to the boiler control unit
CPREG which leads the pump operation and prevents the boiler cooling (not cool down to much).
6.2.1. SOLID FUEL FIRING
The draft controller (such as CALEFFI 543, ESBE ATA200) is needed for the boiler temperature
regulation, and it has to be installed on the boiler front left side (see page 5.). The draft controller chain
has to be adjusted in a way that boiler temperature do not exceed the temperature from 85 to 90°C by
normal firing (opening for air is completely closed), and not drop under 65°C. If the boiler is fired with
solid fuel, it is necessary to switch on the boiler control unit CPREG on the main switch, so the pump
can operate correctly and the boiler and domestic water temperature can be shown. Detailed
description of control unit operating is described in the “Technical instructions for use and maintenace
of the control unit and the boiler CentroPlus/CentroPlus-B fired with solid fuel and wooden pellets”
which are delivered with equipment for wooden pellets firing.
6.2.2. WOODEN PELLETS FIRING
Digital control unit CPREG which is installed to the boiler lid (see page 7) it is needed for the
temperature regulation. It is necessary to connect the pump of the heating system and domestic water
to the regulation CPREG which leads the pump operation and prevents boiler to not cool down to
much. For detailed description of control unit CPREG operating see “Technical instructions for use and
maintenace of the Cm Pellet-set for the boilers CentroPlus and CentroPlus-B (fired with solid fuel and
wooden pellets)” which are delivered with equipment for wooden pellets firing.
6.3. BOILER FIRED WITH SOLID FUEL AND EL FUEL OIL
It is necessary to connect the pump of the heating system through the pump thermostat to the control
unit according to the Scheme 6, which (if the pump switch is set on 1) switch the pump on if boiler
temperature exceed 68°C or switch it down if boiler temperature drop under 68°C. In that way the boiler
is prevented from excessive cooling.
6.3.1. BOILER FIRED WITH SOLID FUEL
The draft controller (such as CALEFFI 543, ESBE ATA200) is needed for the boiler temperature
regulation and it has to be installed on the boiler front left side (see page 5). The draft controller chain
has to be adjusted in a way that boiler temperature do not exceed the temperature from 85 to 90°C by
normal firing (opening for air is completely closed), and do not drop under 65 °C. The switch for heating
pump operation has to be turned on at the boiler contol unit EKO-CK/CKB (Figure 5., position 3), if
boiler is fired with solid fuel.
19
Boiler temperature regulation
Technical instructions CentroPlus

6.3.2. EL FUEL OIL FIRING
Temperature in boiler is controlled by boiler control unit EKO-CK/CKB which is installed to the boiler lid
(see page 6). On boiler control unit EKO-CK/CKB the burner has to be switched on (Figure 5, position
1) and it is necessary to adjust the regulation thermostat to the preferred boiler temperature (70-90°C).
6.3.3. THE BOILER CONTROL UNIT solid fuel/EL fuel oil
1. BOILER SWITCH
The switch with signal lamp for burner switching on and off.
2. BURNER SIGNAL LAMP
If there are some faults in the burner operation, this lamp will appear.
3. THE SWITCH FOR SYSTEM PUMP
The switch with signal lamp for pump switching on and off.
4. THE BOILER CONTROL THERMOSTAT
The control range of boiler operating temperature (35 - 90°C) is controlled by button rotation.
5. SAFETY THERMOSTAT
It stops the burner operation if the boiler temperature exceeds 98°C and in that way prevent system
against damage.
To restart the burner, following steps must be taken:
- wait until boiler temperature falls below 70°C
- push the button, position 5, Figure 5.
If there are still frequent interruptions during the boiler operation, call the authorised person to
check the boiler.
Figure 5.: The basic boiler control unit
4 1 3
°c
0 1 10
°c
2
5
20
Boiler temperature regulation
Technical instructions CentroPlus