Coopra TWIN80C User manual

EN
Installation Manual
TWIN80C
Wall hung, fan flue, room sealed, high efficiency gas boiler
CHAPTER 1. GENERAL
CHAPTER 2. INSTALLATION
CHAPTER 3. COMMISSIONING
CHAPTER 4. FAULT FINDING
CHAPTER 5. PERIODICAL MAINTENANCE
CE-CERTIFICATE
2007 E000129016

installation manual TWIN 80 EN
2
CONTENTS
CHAPTER 1. GENERAL
1.1. Technical data……………………………………………………………………………………………………………… 04
1.2. Dimensional sketch…………………………………………………………………………………….………………….. 05
1.3. Boiler layout…………………………………………………………………………………………….…………………… 06
1.4. Diagrams
1.4.1. Functional flow diagram………………………………………………………………….……………………. 08
1.4.2. Wiring diagram…………………………………………………………………………..…………………….. 09
1.5. Condensing boiler………………………………………………………………………………………………………….. 10
1.6. Operation
1.6.1. Display
1.6.2. Master – Left hand side printed circuit board.
1.6.3. Slave –right hand side printed circuit board.
1.7. LED indication
1.8. Permitted flue discharge and air supply resistance………………………………………………………..…………… 11
1.8.1. “Concentric flue and air” system
1.8.2. “2 pipe” system
1.9. Configurations……………………………………………………………………………………………………………… 12
1.10. Regulations
CHAPTER 2. INSTALLATION
2.1. Mounting………………………………………………………………………………………………..……………………. 13
2.1.1. Bracket
2.1.2 Adapter
2.1.2.1. “Concentric flue and air” system
2.1.2.2. “2 pipe” system (100/100)
2.1.3. Boiler
2.2. GAS………………………………………………………………………………………………….………………………. 14
2.3. WATER
2.3.1. Safety valve
2.3.2. Filling and straining device
2.3.3. Expansion vessel……………………………………………………………………………………….………………… 15
2.3.4. Dirt filter
2.3.5. Differential bypass valve
2.3.6. Condensation discharge
2.4. PUMP………………………………………………………………………………………..………………………………. 16
2.4.1. Unit system pump
2.4.2. External system pump (option)
2.5. ELECTRICAL……………………………………………………………………………………………………………….. 17
2.5.1. Supply connection
2.5.2. Supply fuse
2.5.3. Input
2.5.4. Output
2.5.5. Cascade connection of master and slave
2.6. Lay-out BIC992………………………………………………………………………………….………………………….. 18
2.6.1. Connectors & pinning
2.6.2. Table, pinning
2.7. Green connector block……………………………………………………………………………………………….……. 19
2.7.1. 24 Volt on/off room thermostat (standard)
2.7.2. 0-10 Volt input regulation (standard)
2.7.3. OpenTherm (standard)
2.7.4. Outdoor sensor (standard)
2.8. Options with installer responsibility……………………………………………………………………………………….. 20
2.8.1.
2.8.2. 230 Volt room thermostat (installer responsibility)
2.8.3. Remote alarm (installer responsibility)
CHAPTER 3. COMMISSIONING
3.1. Filling…………………………………………………………………………………………………………..…………….. 21
3.2. Reading the water pressure
3.3. Venting

installation manual TWIN 80 EN
3
3.4. Chimney sweeper function
3.5. Gas/Air Ratio………………………………………………………………………………………………..………………..22
3.5.1. Pre-adjustment to be done in voltage-free condition:
3.5.2. Final Gas/Air adjustment (CO2 analysing)
3.6. Conversion to LPG…………………………………………………………………………………………………………. 23
3.7. MENU STRUCTURE……………………………………………………………………………………………………….. 24
3.7.1. Outdoor temperature sensor……………………………………………………………..…………………… 25
3.7.2. Domestic hot water (3-Way valve and cylinder to initiate by installer)
3.8. CASCADE……………………………………………………………………………………………………………..…….. 26
3.8.1. Power mode (default)
3.8.2. Comfort mode (field adjustable)
CHAPTER 4. FAULT FINDING
4.1 Boiler states…………………………………………………………………………………………………………………. 27
4.1.1. Standby
4.1.2. Pre rinse
4.1.3. Ignition
4.1.4. In operation
4.1.5. Post rinse
4.1.6. Pump after run
4.2. Status indications
4.2.1. Status indication during “operation mode”………………………………………………………………….. 29
4.2.2. Status indication during “blocking action”……………………………………………………….………….. 31
4.2.3. Status indication during ”lock-out”…………………………………………………………………………… 33
4.2.4. Chimney sweeper function (temporarily display for service purposes)…………………………..……… 35
CHAPTER 5. PERIODICAL MAINTENANCE
5.1. Checking the CO2 percentage……………………………………………………………………..……………..………. 36
5.2. Measuring the load of the unit
5.3. Cleaning the condensation water drain
5.4. Ionisation probe
5.5. Water pressure
CE-CERTIFICATE…………………………………………………………………………………………………………………….……. 37

installation manual TWIN 80 EN
4
CHAPTER 1. GENERAL
1.1. Technical data
Boiler type 80C
Gas type natural gas G20 LPG gas G30/G31
Supply / Frequency 230 V / 50 Hz
(195 ÷ 270V @ 47,5 ÷ 52,5Hz)
Power consumption (max.) 280 W
Electrical data
Thermostat voltage 24 Volt / OpenTherm / 0-10V
Height 950 mm
Width 710 mm
Depth 360 mm
Dimensions and
weight
Weight 65 kg
CO28.2% - 8.8% 9.2% - 9.8%
CO (0% 02) 12 –100 ppm
Emission value
NOX(0% O2) 10 – 30 ppm
at 80/60ºC < 70ºC
Flue gas-
temperature at 50/30ºC < 35ºC
Max. chimney
resistance Air feed and flue tube together 125 Pa
Gas G 3/4 ” outside
Heating (flow and return) G 1 1/4” outside
Connections
Overflow siphon
Air feed and flue
tube system Concentric system Ø 100 / 150 mm or Ø 110 / 150 mm
Water contents 4 L
Max. temperature 90°C
Max. operating pressure 3.2 bar
Boiler heat
exchanger
Max. system pressure 4 bar
Pump high 45 dB(A)
Sound level
Pump low 35 dB(A)
Certification CE Identification number CE0063-AT3070
Cascade selection : menu parameter “.o” = 1 TWIN in power mode
Gas type natural gas G20 LPG gas G30/G31
Nominal gas pressure 20 mbar 37/50 mbar
Heat input (gross) 16.2 – 82.2 kW
Heat input (net) 14.6 – 74.0 kW
Nominal output at 80/60ºC 14.1 – 72.0 kW
Nominal output at 50/30ºC 15.6 – 75.3 kW
Efficiency at 80/60ºC (net) Low load = 96.6 %; High load = 97.2 %
Gas technical
data
Efficiency at 50/30ºC (net) Low load = 106.9 %; High load = 101.8 %

installation manual TWIN 80 EN
5
1.2. Dimensional sketch
Dimensions in mm
Free space: There must be sufficient space at the top and bottom to be able to suspend the unit and to be able to connect all feed
and drain pipes. Normally, roughly 300 mm is required.
It is recommended to leave a free space of 150 mm on the left (for servicing reasons) and 50 mm on the right of the unit.
The front of the unit must be easily accessible for servicing at all times.
Connections
Pos 1 = Flow connection G1¼” male tread
Pos 2 = Return connection G1¼” male tread
Pos 3 = Gas connection G¾” male thread
Pos 1
Pos 3
Pos 2

installation manual TWIN 80 EN
6
1.3. Boiler layout

installation manual TWIN 80 EN
7
pos description Beschreibung omschrijving No.
01 Assembly frame Montagekasten Achterwand 1x
02 Cover Mantel Voorkap 1x
03 Flow collector Vorlauf-Versammelrohr manifold aanvoer 1x
04 Return collector Rücklauf-Versammelrohr manifold retour 1x
05 Gas collector Gas-Versammelrohr Gas-manifold 1x
06 Unit type 40 Wärmetauscher Typ 40 Ketellichaam type 40 2x
07 Burner type 40 Brenner Typ 40 Brander type 40 2x
08 Pump Pumpe pomp Wilo RS15/7-2ku 2x
09 Internal flow pipe Vorlaufrohr Leiding aanvoer 2x
10 Kst. pump type 40 Kst.Pumpe Typ 40 Kst. pomp type 40 2x
11 Internal return pipe Rücklaufrohr Leiding retour 2x
12 Kst. flow type 40 Kst.Vorlauf Typ 40 Kst. aanvoer type 40 2x
13 Sealing plug Dichtung plug Ø33,5 1x
14 Ionisation probe Ionisationssonde ionisatiepen Beru 2x
15 Glow plug Glühzünder gloeiontsteker 230 VAC 2x
16 Temperature sensor pipe Temperatursensor Aanlegvoeler buis Ø 22 4x
17 manager Brennerautomat besturing SIT master / slave 1x
18 Safety valve Sicherheitsventil overstortventiel Emmeti 3,2 bar 1x
19 plug Dichtung plug G½” 1x
20 manual vent Handentlüfter handontluchter 2x
21 Manifold exhaust Kaminstück Broekstuk rookgasafvoer 1x
22 Nipple condensate tray Verbindungsstück Slangpilaar condensbak 1x
23 Sealing condensate tray Dichtung Kondensatwanne Pakking condensbak 2x
24 Sealing ring Dichtring Doorvoerrubber condensb. 2x
25 Connection siphon Siphonanschlussstück Aansluitbuis sifon 1x
26 Connection nut Verbindungsmutter connectiemoer G1½” 2x
27 Tube of safety valve sicherheitsventilschlauch overstortslang Ø19 x Ø13 1x
28 Strain relief Ziehentlaster kabelwartel 22-32 M40 1x
29 Sealing ring Dichtring pakkingring 1” 8x
30 Sealing ring Dichtring doorvoertule Ø38 x Ø24,9 1x
31 Flue gas sensor Abgastemperaturfühler Voeler rookgas Tasseron 2x
32 Cil.screw Zilinderkopfschraube Cil.schroef met bzk M6 x 12 6x
33 screw schraube Zelfdraadv.schroef M3 x 8 12x
34 Green connection block Grüne Anschlussblock Steker 6-polig 1x
35 Strain relief Ziehentlaster PG-wartel Onkenhout 1x
36 Nut for strain relief Ziehentlastermutter Contramoer PG-wartel Onkenhout 1x
37 Valve extension Ventilverlängerung kraanverlengstuk 1x
38 Nipple male/male Verbindungsnippel Dubbele nippel G¾” x G¾” 1x
39 plug Dichtung plug Ø12 6x
40 Fixation bracket Fixierungsbügel Fix.beugel aanvoerleiding 2x
41 Pressure sensor Drucksensor Druksensor Huba / IMIT 2x
42 Filling/straining device Fühl/Entlehrhahn Radiator aftapkraan G½” 1x
43 El. connection material El. Verbindungsmaterial kabelbundelband 25x
44 Cil.screw Zilinderkopfschraube Cil.schroef met bzk M6 x 60 10x
45 Sealing flowpipe Dichtung Vorlauf Afdichting aanvoerleiding 4x
46 Sealing ionisation probe Dichtung Ionisationssonde Pakking ionisatiepen 2x
47 Sealing glow plug Dichtung Glühzünder Pakking ontsteekpen 2x
48 Condensate tube Kondensatabfuhrschlauch condensafvoerslang 2x
49 0-ring 0-Ringe 0-ring Ø15,54 x Ø2,62 4x
50 Connection nut Verbindungsmutter connectiemoer G¾” 1x
51 Bracket manifold L. Bügel Versammelrohr L. Sluitplaat manifold L. 1x
52 Bracket manifold R. Bügel Versammelrohr R Sluitplaat manifold R. 1x
53 Bracket flue pipe Bügel Abgasrohr Kapbeugel broekstuk 1x
54 Cil.screw Zilinderkopfschraube Cil.schroef met bzk M6 x 20 8x
55 LED with wire LED mit Schnur LED met kabel 2x
56 Nut for strain relief Ziehentlastermutter Contramoer kabelwartel M40 1x
57 Nut Mutter knelmoer G½” x 15 2x
58 sleeve Klemmring knelring Ø15 2x
59 Sealing ring gas Dichtungsring Gas Pakkingring gas G¾” 2x
60 Sealing ring Dichtungsring pakkingring Ø25 x Ø21 x 1,5 1x

installation manual TWIN 80 EN
8
1.4. Diagrams
1.4.1. Functional flow diagram
Ventilator
325Vdc
Pump
230 Vac
V+
V-
Hall
RS232S
PE
N
L
230 Vac
BURNER
Gasvalve
230 Vrac
Supply
Return
Flue
Outside
DHW
Roomtherm.
Roomtherm.
Safety
Waterpressure
sensor
BMS
OpenTherm
RS-485
Waterpressure
switch
_t
_t
_t
_t
_t
BIC-992
X17-6
X17-2
X16-7
X16-6
X18-1
X9-2
X1-4
X4-5
X6-4
X4-4
X8-1
X8-3
X8-4
X8-5
X8-6
X8-2
X2-1
X2-2
X2-1
X2-3
X2-2
X2-4
X3-4
X20
-2
X2-5
X5-1
X5-2
X5-3
X3-5
X20-1
X4-3
X22-1
X4-1
X22-2
X6-1
X6-3
X17-3
X17-5
X16-3
X16-2
X18-3
X9-1
X1-3
X4-6
X15-3
X19-1
X11-2
X10-1
X7-4
X7-2
X7-1
X15-1
X15-2
X19-2
X11-1
X10-2
0 - 10 V
24Vac
230Vac
230VAC
IO
PE
PE
L1
L2
L1
L1
L3
L2
PE
Running/Lockout
LED
12Vdc
Threewayvalve
CH externe pump
pe
pe
hsi
L1
L2
ALARM
+

installation manual TWIN 80 EN
9
1.4.2. Wiring diagram

installation manual TWIN 80 EN
10
1.5. Condensing boiler
The concentric air inlet and exhaust outlet need to be
connected with one of the adapter sets.
The TWIN 80C is a wall hung, fan flue, room sealed, high
efficiency condensing gas boiler for central heating and / or
under floor heating systems.
The type plate, which specifies the type of gas etc. to be used, for
which the unit is set, is on the left side of the unit.
1.6. Operation
The appliance is equipped with pre-set gas/air ratio regulators.
The purpose of this regulator is to keep the gas/air ratio in the
burner as optimal as possible at all times e.g. when modulating.
This ensures clean and reliable combustion across the entire
load range. In addition it achieves high part-load efficiency.
The TWIN 80C incorporates 2x type 40C heat units (existing of
2x heat exchanger, 2x premix burner, 2x fan, 2x gas valve, 2x
venturi, 2x circulation pump, 2x printed circuit board). Each heat
burner works independently, cascade controlled by two printed
circuit boards.
A fan sucks the air required for the combustion through the air
feed canal (A). Because the combustion air in the venturi sucks
an under pressure, the correct amount of gas (G) is
automatically added to the combustion air.
The flammable gas/air mixture thus obtained is fed to the
burner(s), via a mixing chamber, to be ignited at the surface of
the burner(s) by a ceramic glow plug. The hot combustion gases
are efficiently fed through the heat exchanger(s), where they
give their heat to the system water. The flue gases are fed
outdoor, through the flue tube (F), into a combined flue tube
exhaust canal.
The formed condensation water (H2O) is discharged through the
waste trap.
1.6.1. Display
The display operates for both printed circuit boards.
Open the door in front of the jacket for operating and reading the
codes on the display, - The boiler of this picture is in the
stand-by mode, because the display
shows a continuous 0.
- The actual water temperature of
the flow sensor is 19‘C.
1.6.2. Master – Left hand side printed circuit board.
The Master is the leading board, calculates and divides the
necessary power over both units. Therefore the regulation
controls will always be connected to the Master.
•Room thermostat 24 Volt default
•Outdoor temperature sensor default
•OpenTherm regulation default
•Room thermostat 230 Volt optional
•Direct control 0-10 Volt optional
Note: Spare part boards are set for SLAVE.
If needed, make SLAVE (A=1) into MASTER (A=0).
1.6.3. Slave –right hand side printed circuit board.
In case of a lock-out of the Master printed circuit board the Slave
is still able to operate correctly.
1.7. LED indication
Two LED’s have been placed under the appliance informing the
user the status of each unit individually.
The left hand side LED (L) is indicating the actual status of the
Left hand side heating unit.
•LED is ON = burner concerned is ON
•LED is OFF = burner concerned is OFF
•LED is FLASHING = unit concerned is LOCK-OUT
The right hand side LED (r) is indicating the actual status of the
right hand side heating unit.
•LED is ON = burner concerned is ON
•LED is OFF = burner concerned is OFF
•LED is FLASHING = unit concerned is LOCK-OUT
Concentric
100/150 mm
N00M990080
Concentric
110/150 mm
N00M990082
or
or

installation manual TWIN 80 EN
11
1.8. Permitted flue discharge and air supply resistance
The total resistance of the flue tube and air supply together
may not be greater than 125 Pa.
Indication for the resistance values given in table below apply to
-Flue exhaust flow rate of max 122 m3/hour (at 70 ‘C)
-Supply air flow rate of max 96 m3/hour (at 20 ‘C)
1.8.1. “Concentric flue and air” system
Concentric system Ø 110/150 mm Ø 100/150 mm
Type 80
Tube per metre 7.5 Pa 9.4 Pa
Bend 90°, R = 1.5 D 7.5 Pa 9.4 Pa
Bend 90°, R = 0.5 D 12.0 Pa 15.0 Pa
Bend 45°, R = 1.5 D 6.0 Pa 7.5 Pa
Bend 45°, R = 0.5 D 10.0 Pa 12.5 Pa
Roof duct 1.25 m 40.0 Pa 40.0 Pa
The concentric system 110/150 mm has been tested. The
test result show a maximum length of 10 meters
horizontally, including 1x bend of 90’ and a standard roof
duct.
Using the system 100/150 mm will reduce the maximum
length to 8 meters.
Please note each additional bend shortens the total
length with a meter in length.
1.8.2. “2 pipe” system
“2 pipe” system Ø 110 mm Ø 100 mm
Type 80
Tube per metre 3,7 Pa 4.6 Pa
Bend 90°, R = 1.5 D 3.7 Pa 4.6 Pa
Bend 90°, R = 0.5 D 6.0 Pa 7.5 Pa
Bend 45°, R = 1.5 D 3.0 Pa 3.8 Pa
Bend 45°, R = 0.5 D 5.0 Pa 6.2 Pa
Roof duct 20.0 Pa 25.0 Pa
1.9. Configurations
Preferably use flue tube materials, roof ducts and exterior wall
ducts with a quality mark.
For the use of plastic exhaust pipes both units are protected with
a flue gas temperature sensor.
In normal operation the application may produce a visible white
condensing “plume”.
The TWIN is approved for application on the drain systems:
B23, C13(x), C33(x), C43(x), C53, C63(x), C83(x).

installation manual TWIN 80 EN
12
1.10. Regulations
In case of non-compliance with the regulations, no
claims can be made against the guarantee conditions.
General safety regulations
The installation may only be performed by a recognised installer.
Take note that internal parts of the unit can carry a dangerous
electrical voltage (230 Volt).
Take note that the unit, the various pipes and the flue gas
exhausted by the unit can reach high temperatures (up to 90°C).
Before carrying out maintenance activities in or on the unit, you
must close the gas tap, switch off the electricity supply and pull
the mains plug out of the socket.
Environmental conditions
The area in which the unit is installed must satisfy the applicable
regulations.
The wall must be able to bear the weight of the unit (loaded
weight approx. 40 kg).
If you use a different assembly surface than a bricky wall of
sufficient thickness, you must select suitable fixtures yourself
and properly install the unit.
The unit may not be fitted in a chemically aggressive
environment.
The unit with air feed and flue gas exhaust satisfies the
requirements of protection class IP44 and may therefore be
installed in a wet area.
Although the unit is fitted with an internal frost protection, it may
not be exposed to extremely low ambient temperatures (lower
than -10°C).
Standards / Guidelines
With the installation of the unit, all local regulations must be
followed, where applicable, including the provisions of the
following standards and guidelines:
•Building Regulations
•Regulations for natural gas installations
•Regulations for LPG (if applicable)
•Guidelines for existing gas installations
•Safety requirements for central heating installations
•Safety provisions for low voltage installations
•General regulations for drinking water installations
•Water authority regulations
•Ventilation in dwellings
•Supply of combustion air and exhaust
•House sewerage in homes and dwellings
•Fire Brigade regulations
•Factory Act regulations
•Regulations applicable to HWS water Ask for the
locally applicable regulations at the local water
company as they are different in some areas

installation manual TWIN 80 EN
13
CHAPTER 2. INSTALLATION
2.1. Mounting
Before unpacking the unit, check whether the type of gas to be
used corresponds with the specification on the packing. If you
have any questions, contact your supplier.
To prevent back injury, take account of the fact that the weight of
the unit is roughly approx 65 kg. Care should be taken when
unpacking and mounting the appliance.
2.1.1. Bracket
To mount the appliance on a brick wall of sufficient thickness,
use the bracket supplied.
When you have determined the place of assembly, proceed as
follows:
•Draw the position of the bracket onto the wall.
•Use a masonry drill of 6 mm diameter to drill the holes with a
sufficient depth in the wall.
•Fit the plug’s in the drilled holes.
•Fix the bracket with the screw supplied.
2.1.2 Adapter
2.1.2.1. “Concentric flue and air” system
Mount one of the adapter systems onto the boiler.
Adapter Muelink & Grol 100/150
(art. N00M990080)
Adapter Cox Geelen 110/150
(art. N00M990082)
•Fit either the Muelink & Grol adapter for the
connection of a concentric air intake and exhaust gas
outlet system of 100/150 mm or the Cox Geelen
adapter for the connection of a concentric air intake
and exhaust gas outlet system of 110/150 mm on top of
the boiler.
•Fit later the concentric pipes onto the adapter
concerned.
2.1.2.2. “2 pipe” system (100/100)
Use the adapter 100/150 (Muelink & Grol) also for connection of
a “2 pipe” system (100/100) system and use the sealing ring
supplied to seal the air intake.
When the flue tube and air supply are connected eccentrically,
proceed as follows:
•Fit the flue tube of diameter 100 mm in the opening, in
the adapter on top / left hand side of the boiler.
•Fit the air supply of diameter 100 mm in the flange on
top / right hand side of the boiler.
2.1.3. Boiler
To prevent back injury, take account of the fact that the
weight of the unit is roughly approx 65 kg. Care should be
taken when unpacking and mounting the appliance.
•Mount the appliance (TWIN boiler and adapter) onto the
bracket.
•A-line the boiler horizontally.
•Fix the position.

installation manual TWIN 80 EN
14
2.2. GAS
Make sure that the gas pipe work does not contain
dirt, particularly with new pipes.
Failure to install gas-appliances correctly could lead to accidents
and prosecution. It is in your own interest, and that of safety, to
ensure that the law is complied with.
G¾” (male thread)
•The appliance has to be connected in accordance with the
current regulations.
•Supply pipe works to be sized in accordance with relevant
regulations.
•We advise a gas filter be fitted in the gas supply line in order
to prevent contamination of the gas valves.
•Connect the gas pipe to the gas connection positioned under
the appliance in the middle. The appliance is equipped with
male gas thread G¾”.
•Install the gas pipe stress free.
•Include the gas pipe with an approved stopcock.
2.3. WATER
Both of the heat units are parallel jointed to central flow- and return water
collectors.
WATER
G1¼” (male thread)
Connect the central heating flow pipe to pos 1 with G1¼” male
thread of the the collector on the far side.
Connect the central heating return pipe to to pos 2 with G1¼”
male thread of the collector on the nearr side.
2.3.1. Safety valve
The boiler has been provided with a
safety valve of 3.2 bar.
The discharge under the boiler should
determinate facing downwards exterior to
the building in a position where
discharging water will not create danger
or nuisance but remains in a visible
position.
2.3.2. Filling and straining device
On the return collector of the boiler is a connection 1/2”
BSP female thread for the filling and straining device.
Install the filling and draining device,
packed with the boiler, onto this
connection in the central heating return
system. Do not use the safety valve as a
drain. The safety valve may not close
properly after passing contaminated
system water.

installation manual TWIN 80 EN
15
2.3.3. Expansion vessel
In the central heating return pipe, as near as to the boiler, an
expansion vessel must be fitted.
The size of the expansion vessel must
be determined on the basis of the central
heating water temperature and the total
water content the installation contains.
Example of Emmeti “Expansion vessel”
The pre-pressure depends on the installation height above the
mounted expansion vessel.
5 meter - 0,5 bar
10 meter - 1,0 bar
15 meter - 1,5 bar
2.3.4. Dirt filter If it may be expected that the central
heating water will be severely
contaminated by under floor heating,
fitting a 2 kg dirt fine filter in the return
pipe is recommended. With this, possible
contamination of the central heating
water is prevented from ending up in one
of the units.
Coopra cannot give any guarantee for
damage to the unit that is caused by dirt
in the system.
Example of PermaTrade “dirt filter” type PT-FM-25W
2.3.5. Differential bypass valve
A differential bypass valve must be installed on plants where it
may happen that various heating units (radiators) are
simultaneously excluded from the circuit because of the closure
of control or zone valves. It ensures a
recirculation proportional to the number
of shut off valves, thus avoiding noise
and keeping the pump pressure steady.
Example of Caleffi “Bypass valve”
type 519500 (¾”)
Mounting: The differential by-pass valve
must be mounted in the installation
between the flow and the return piping. It
may be mounted both horizontally and
vertically, provided that flow direction indicated by arrow is
respected.
Adjustment: Rotate knob on the desired value of the graduated
scale. The values correspond to the meters of pump head (m
H2O). The advised knob setting is 2.5-3.0. Lock the screw on the
groove knob.
2.3.6. Condensation discharge
Mounting: The siphon (packed with the
boiler) fits onto the discharge pipe (Ø 32
mm) under the boiler. Tighten this
connection with the sealing ring and fix
the nut manually by hand.
The outlet of the siphon has to be
connected to the drain with a tundish.

installation manual TWIN 80 EN
16
2.4. PUMP
2.4.1. Unit system pump
The TWIN 80C is equipped with 2x Wilo, type RS 15/7 internal circulation pumps. Depending of the cascade selection and heat
demand one pump may run intermittent or both pumps may run simultaneously.
Use with a low velocity header (open header) can also be selected. In this case a larger secondary sided water output has to be
taken into account, in order to affect the height of the water temperature.
Fig.: Characteristic and the resistance graph of the application when
both unit pumps run.
2.4.2. External system pump (option)
If the capacity of the unit pumps is insufficient, an extra external system pump can be installed with the appliance.
The maximum absorbed current consumption of the external circulation pump may be 275 W (1,2 Amp).
On command of the printed circuit board, an external second system-pump will switch with the internal boiler-pump simultaneously.
Note the internal pump will switch high/low/off (2-stage) while the external pump will switch on/off (1-stage).
External system pump
230VAC
max
275W (1 2
Amp
)
Terminal X5
printed circuit board
4 way Molex header 0 2
”
pitch
Neutral
Earth
Line
Neutra
l
Earth
Lin
e

installation manual TWIN 80 EN
17
2.5. ELECTRICAL
2.5.1. Supply connection
If a stationary appliance is not provided with a supply cord
and a plug or with other means for disconnection from the
supply having a contact separation of at least 3 mm in all poles,
the instructions shall state that such means for disconnection
must be incorporated in the fixed wiring.
If a stationary appliance is provided with a supply cord and a
plug in the instructions shall state that the appliance must be
positioned so that the plug is accessible
There must be an electrical outlet with Earth connection
available at a maximum distance of 1 m from the unit.
The electricity connection (230 VAC) must consist of Line,
Neutral and Earth and a good Earth connection (requirement for
good ionisation operation of the appliance).
If the supply cord is damaged, it must be replaced by the
manufacturer or is service agent or similarly qualified person in
order to avoid a hazard.
If the display of the unit gives the status code ‘U’, this
means the Line and Neutral connections are reversed.
2.5.2. Supply fuse
If Master fuse fails the Slave
printed circuit board cannot get
commands from the Master to
take over processing.
If Slave fuse fails the Master
printed circuit board wil operate
normally and can heat the
system with one single unit.
2.5.3. Input
Temperature sensors: 5Vdc ± 5%, R25 = 12kΩ, ß = 3980
Water pressure sensor: 12Vdc ± 20%, Ri = 100kOhm
0÷10V : Ri = 20kOhm
Room thermostat: 24Vac (standard)
Room thermostat: 230Vac (option)
OpenTherm: available on main board
1kHz, Manchester encoding conform specification 2.0
RS-485 : cascade input, SIT protocol
Ionisation: detection 100Vac
2.5.4. Output
Glow plug: single switched 230Vac
Gas valve: double switched 230Vac
Fan : 325Vdc
Pump: unit system pumps (2-stage speed operated)
In operation/lock-out LED: 10mA dc
External lock-out contact: potential free contact
External system pump 230VAC max. 275W (1,2 Amp)
External 3-way valve and HWS cilinder
2.5.5. Cascade connection of master and slave
Bus protocol: RS-485 (TIA/EIA-485-A)
Polarity: phase depending
Wiring: 2 wires (A and B),
Twisted pair, no shield
Shut-off resistance: not needed
Galvanic isolation: not needed
Communication: 9600 Baud
Master and Slave: Connected to the same PE-Line
F1
Supply Fuse
3.15 AT
cascade
connection
between
the red
terminals

installation manual TWIN 80 EN
18
2.6. Lay-out BIC992
2.6.1. Connectors & pinning
X1 4-way Molex header 0.2” pitch
X2 5-way Molex header 0.2” pitch
X3 5-way Molex header 0.2” pitch
X4 6-way Molex header 0.2” pitch
X5 3-way Molex header 0.2” pitch
X6 4-way Molex Minifit
X7 4-way Molex header 0.2” pitch
X8 6-way Molex header 0.2” pitch
X9 2-way Molex Minifit (white)
X10 2-way Molex Minifit (red)
X11 2-way Molex Minifit (blue)
X12 10-way latch connector for display
X15 4-way Molex Minifit
X16 8-way Molex Minifit
X17 6-way Molex Minifit
X18 4-way Molex Minifit
X19 2-way Molex Minifit
X20 2-way Molex Minifit (black)
X22 2-way Molex Minifit (black)
2.6.2. Table, pinning
X1 X2 X3 X4 X5 X6 X7 X8 X9 X10 X11 X15 X16 X17 X18 X19 X20 X22
1 PE PE PE PE PE HSI PE PE 24V RS-485
(B) Open Therm input Ext. tan
k
0V +12v contac
t
2 N N N N
pump2 N L1, fan Rth RS-485 (A) Open Therm 12V+ outdoo r return Ext. tan
k
0÷10V Led
1K contac t
3 L N’,
gas valve L pump2 ionisa- tion L2, fan 12V- flue flow
4 Rth L’,
gas valve HSI L V-
5 L1,
pump Max Th Hall return
6 Max Th,
24Vdc V+ outsid e flow
7 flue
8

installation manual TWIN 80 EN
19
2.7. Green connector block
The external regulations are to be connected to the green connector block.
All connections are volt-free contacts. Therefore, do not connect any
voltage to this block!
1. Strip about 5 mm off the insulation of the wires of the connection
concerned.
2. Stick the stripped ends of the wires into connections of the connection
block involved.
3. Make sure that the wires do not make a short circuit.
4. Firmly tighten the screws in the connection block.
2.7.1. 24 Volt on/off room thermostat (standard)
- When the room thermostat is closed (heat demand), the set
point (desired central heating flow temperature) rises at a rate
of 2°C per minute until the maximum permissible central
heating flow temperature is reached (21 minutes from minimum
25°C to 82°C).
- When the room thermostat is open (end of heat demand), the
set point (desired central heating flow temperature) falls at a
rate of 4°C per minute to the minimum central heating
temperature (10.5 minutes from 82°C to minimum 25°C).
•Connect the 24 Volt room thermostat to the green
connector block on contacts (1) and (2)
•On the master print check the connection of the
white terminal (default)
2.7.2. 0-10 Volt input regulation (standard)
- The set point indicates whether there is a heat demand.
- The desired central heating flow temperature (set point) is
given by the 0-10 Volt input.
- The regulation is field adjustable in the menu either on
temperature (°C) or on boiler input (kW)
•Connect the 0-10 Volt regulation to the green
connector block on contacts (1) and (2)
•On the master print check the connection of the
white terminal (default)
2.7.3. OpenTherm (standard)
- The desired central heating flow temperature (set point) is
indicated by the modulating OpenTherm room thermostat.
- With an outdoor temperature sensor, the measured outdoor
temperature is sent to the OpenTherm room thermostat, which
uses it to calculate the desired central heating flow
temperature.
•Connect the OpenTherm modulating room
thermostat to the green connector block on
contacts (1) and (2).
•RE-PLUG the connector of the Master to the blue
terminal (Master).
2.7.4. Outdoor sensor (standard)
- When an external outdoor temperature sensor (heating) is
connected, the sensor must be an NTC with a resistance of
12kOhm at 25°C
•Connect the outdoor sensor to the green
connector block on contacts (3) and (4).
24Volt on/off room thermostat
or
0-10Volt input
(if no regulation is used - bridge wire)
contacts (1) - (2)
room thermostat
OpenTherm
contacts (3) - (4)
outdoor sensor external outdoor temperature sensor
(NTC of 12 kOhm at at 25°C)
contacts (5) - (6)
external cylinder
10 kOhm sensor
or
12 kOhm sensor
or
cylinder thermostat (on/off)
Green connector block Maste
r
p
rint

installation manual TWIN 80 EN
20
2.8 Options with installer responsibility
2.8.1.
2.8.2. 230 Volt room thermostat (installer responsibility)
All Coopra printed circuit boards have a terminal for connection
of a line voltage 230 Volt room thermostat.
•At present Coopra does not supply any connection
cable for this option.
Pinning TERMINAL X1
pin X1
1 PE = Earth
2
3 N
4 230VAC
room
thermostat
5 L
2.8.3. Remote alarm (installer responsibility)
All Coopra printed circuit boards have a remote lock-out
contact. This contact is potential free. The power for an external
signal, lamp or siren, has to be from external.
•At present Coopra does not supply any connection
cable for this option.
Pinning TERMINAL X22
pin X22
1 contact
2 contact