Centrometal STB 200 Owner's manual

TECHNICAL INSTRUCTIONS
Installation, use and maintenance
of solar water heater
TU-STB-02-2022-ENG
STB 200 - 850
HEATING TECHNIQUE
Centrometal d.o.o. - Glavna 12, 40306 Macinec, Croatia, tel: [phone], fax: [phone]
ENG

Basic parts technical data,
2
4
3
5
1
1. Cold domestic water inlet
2. Hot domestic water outlet
3. Recirculation
4. Top (boiler) heat exchanger
5. Bottom (solar) heat exchanger
6. Opening for cleaning
7. Temperature sensor sleeve – heating with
boiler
8. Temperature sensor sleeve – solar heating
9. Thermometar
6
Picture 1. - STB - Basic parts
7
8
9
TECHNICAL DATA
2Technical instructions STB
*¹ Internal thread
*² External thread to ermeto fitting Ø 22-3/4" for STB-200 and Ø 28-1" for STB-300, STB-600 and STB-850
STB 200
Volume
Height C
Boiler diameter Ø A
Diameter without insulation
Depth B
Heat exchanger
Rated thermal output 80°C
70°C
60°C
Heating fluid flow
Heat exchanger surface
Cold domestic water inlet*¹
Hot domestic water outlet*¹
Recirculation*¹
Heat exchanger*²
Maximum working pressure
Mass
(l)
(mm)
(mm)
(mm)
(mm)
(kW)
(l/h)
(kW)
(l/h)
(kW)
(l/h)
(m³/h)
(m²)
(R")
(R")
(R")
(R")
(kg)
300 850600
(1)
top
16,1
395
13,3
325
8,0
195
1,5
0,42
3/4
3/4
3/4
3/4
6 / 0,6
49
bottom
33,1
814
26,7
658
16,5
406
1,5
0,83
top
19,5
479
16,0
391
10,1
391
3
0,53
3/4
3/4
3/4
1
6 / 0,6
66
bottom
37,4
916
28,5
697
18,1
443
1,5
1,06
top
37,6
922
28,9
707
18,4
450
3
1,06
5/4
5/4
3/4
1
6 / 0,6
125
bottom
63,7
1561
49,7
1216
32,5
796
1,5
2,12
top
53,1
1299
40,7
997
26,4
646
3
1,59
5/4
5/4
3/4
1
6 / 0,6
162
bottom
83,8
2053
66,3
1624
44,5
1090
1,5
3,17
198
1420
640
480
690
283
1900
640
480
690
537
1995
810
650
860
850
1940
960
800
1000
(bar/MPa)

Technical data
Slika 2. Solar domestic hot water heater dimensions
B
ØA
90
295
695
775
855
1055
1145
90
295
865
965
1065
1345
1645
75
330
985
1085
1185
1585
1725
Height D
Height E
Height F
Height G
Height H
Height I
Height J
(mm)
(mm)
(mm)
(mm)
(mm)
(mm)
(mm)
STB
200
STB
300
STB
600
70
320
1075
1375
1270
1540
1635
STB
850
C
D
E
F
G
H
I
J
3
Technical instructions STB

Introduction, purpose
1.0. INTRODUCTION
The solar domestic hot water heater STB, by company Centrometal d.o.o., is produced with latest
welding technology, made from quality materials, which ensures high efficiency and the overall product
quality. It is made of stainless steel (INOX) and tested under air pressure of 12 bars. It has two stainless
steel coil heat exchangers. It is delivered factory insulated by 80mm of foam covered with PS jacket.
The technical manual provides information regarding construction, operation, installation and
maintenance, so following to this manual will ensure economic and undisturbed heater operation.
2.0. PURPOSE
Solar water heater is intended for production of the domestic hot water in households, restaurants,
hotels and other area where larger water amount is needed.
The advantage of STB is in using the different energy sources (sun, oil, gas, solid fuel, electrical...),
possibility of producing larger DHW amount, racional consumption of energy sources (oil, gas, solid
fuel, el. energy), excellent insulation and modern effecient construction, which combined results in
lower costs of energy input per produced DHW unit.
Solar heating circuit is connected to the bottom heat exchanger and boiler heating circuit is connected
to the top heat exchangers.
500
1000 2000 3000 4000 5000 6000 7000
B
DC
Heating fluid flow in kg/h
BOTTOM HEAT EXCHANGER
Heating fluid pressure drop
500
1000 2000 3000 4000 5000 6000 7000
0,001
0,002
0,003
0,004
0,005
0,006
0,007
0,008
0,009
0,01
0,02
0,03
0,04
0,05
D
A
B
Heating fluid flow in kg/h
Pressure drop in MPa
TOP HEAT EXCHANGER
Heating fluid pressure drop
0,001
0,002
0,003
0,004
0,005
0,006
0,007
0,008
0,009
0,01
0,02
0,03
0,04
0,05
Pressure drop in Mpa
B
A
C
D
C
A
HEAT EXCHANGER PRESSURE DROP FOR STB 200, 300, 600, 850
200
300
600
850
4Technical instructions STB

Montage, connection to a water supply
4.0. CONNECTION TO A WATER SUPPLY
The water heater connection to a water supply system must be done with accordance with valid
technical standards by a qualified person (Scheme 1). The cold water inlet is the lowest connection on
the heater, marked with a blue rosette, and the hot water outlet is the highest connection, marked with a
red rosette.
On the cold water inlet is obligatory to install following elements:
- domestic hot water expansion vessel
- water heater drain cock (obligatory install it with the T-piece)
- the safety valve (certified to open at 6 bar)
- check valve
- pressure reduction valve to decrease a cold water inlet pressure to the 4 bar (if the pressure is
higher).
The safety valve must be regulary conterolled, limescale must be removed becauce it can block the
flow to the safety valve. The safety valve outlet must be installed in barometric pressure enviroment that
never freezes.
In order to have a longer operation life it is recommend to install a water softener, especially if the heater
is connected to a municipal water supply system (hard water and water with chlorine), and if galvanized
water tubes are used, which can harm stainless steel materials. Recirculation connection is placed
between the top and bottom heat exchanger, marked with red rosette.
A thermostatic 3-way valve and recirculation pump installation must be done upon one of two ways,
depending on the purpose or position of taps.
Scheme 2. shows the recirculation pump installation in the system with two or more thermostatic 3-way
valves. Different temperature can be set for certain group of taps that are placed after the thermostatic
3-way valve. Smaller valve can be selected depending on the number of taps.
Scheme 3. shows the thermostatic 3-way valve installation for all taps, right on the heater hot water
outlet. If even one of the shown elements in the scheme is missing, the recirculation will not work
properly.
The schemes 2. And 3. do not show required elements for connection to the municipal water supply
system, but those elements must be installed as it is shown in Scheme 1.
3.0. MONTAGE
The water heater is factory insulated, with thermometer and ermeto fittings on heat exchanger
connections, and it is delivered on the palette. If it cannot pass through a door, insulation can be taken
off and put on in the room afterwads.
STB is intended for mounting on the flat surface in the room for such application (boiler room, energy
station,…).
5
Technical instructions STB

Connection to a water supply
Scheme 1. Connection to the municipal water supply system
3
45 6 7
2
*
SOLAR DOMESTIC
COLD WATER (ENTRANCE)
1
1 - Solar domestic hot water heater STB
2 - Domestic hot water expansion vessel
3 - Drain cock (T-piece must be used)
4 - Safety valve (6bar)
5 - Check valve
6 - Pressure reduction valve
7 - Shut-off valve
it is required to install if the water supply pressure
is higher than 4bars
*
*
Legend
SOLAR DOMESTIC
HOT WATER
Scheme 2. Recirculation pump installation to the system
with two or more thermostatic 3-way mixing
valves
1
CW
HW
CW
2
5
4
3
Scheme 3. Thermostatic 3-way mixing valve
installation for all taps, right on the heater
hot water outlet, with recirculation pump
1 – water heater
2 – thermostatic 3-way mixing valve
3 – check valve
4 – recirculation pump
5 – shut-off valve
Legend
CW
1
CW
2
2
3
3
3
4
6Technical instructions STB

Connection to the solar and boiler installation
Schema 4. - example of connection to the solar and boiler installation
On scheme 4. is shown an example of solar domestic hot water heater to the solar and boiler heating
circuit. Connections on the heat exchangers are marked with rosettes (red ones on the inlets and blue
ones on the outlets). Connection must be done with ermeto fittings that are factory mounted at the heat
exchanger ends. Before commissioning, air-vent must be done in both systems (solar and boiler).
5.0. CONNECTION TO THE SOLAR AND BOILER INSTALLATION
bar
CW
CW
- solar collector (CPK 7210N, CVSKC-10)
- flat or slope roof collector mounting set
- solar boiler STB
- solar pump group CSPG-TL6600
- solar expansion vessel
- solar air-vent with shut-off valve
- DHW thermostatic 3-way mixing valve
- boiler (EKO-CUP, EKO-CK, El-Cm)
- collector temperature sensor
- boiler temperature sensor
- Cm Sol
- collector return flow
temperature sensor
1
2
3
bar
°C
°C
8
1
2
3
4
4
5
5
6
6
7
8
9
7
99
9
10
9
10
9
11
9
11
912
912
7
Technical instructions STB

As required (depending on the water quality) the hot water heater has to be checked and cleaned from
limescale and the sediment. The opening for cleaning is placed on the lower part of the hot water heater,
at the front, behind the a plastic cover. It is recommended that the cleaning and servicing is carried out
by an authorised technician.
Warranty rights are described in the warranty. Failures and damages of the heater should be reported to
an authorized Centrometal service at the telephone number: [phone]
6.0. MAINTENANCE, CLEANING, WARRANTY AND SERVICE
Maintenance, cleaning, warranty and service
8Technical instructions STB

Declaration of conformity
9
Technical instructions STB

10 Technical instructions STB
Notes

11
Technical instructions STB
Notes

HEATING TECHNIQUE
Centrometal d.o.o. Glavna 12, 40306 Macinec, Croatia
central tel: [phone], fax: [phone]
service tel: [phone], fax: [phone]
Centrometal d.o.o. shall not be responsible for possible incorrect data caused by printing errors or error made in transcription and all figures and diagrams are for
explanatory purposes only and relevant adjustment have to be made at the spot. In any case, it reserves the right to modify its products as deemed to be required
and useful without any prior notification.