4
Set-up and installation
Installation and operating instructions
34
Gas Combi Unit
Floor-standing gas condensing boiler with integrated heat storage
008.1543899_02 – 04/2019 – EN
▪ An external operating mode switch-over can be made by a poten-
tial-free switching contact connected to
terminals 1+2
(EXT). De-
pending on an interconnected resistance and when the switching
contact is closed, the operating mode is switched over to the as-
signed operating mode – see
switch-over via EXT input" function in the "RoCon BF controller"
documentation.
▪ An external heat request can be made by a potential-free switch-
ing contact connected to
terminals 3+4
(EBA). When the switch-
ing contact is closed, the inflow target temperature is set to the
value configured by the [T-Flow Day] parameter on the RoCon BF
controller. The EBA switching contact has priority over a request
from the room thermostat. Switching via the EXT switching contact
has priority over this request.
Terminals 11+12 (t
AG/WP
) are not occupied for these devices and are
available for additional functions.
J3 circuit board connector
An external control, acquisition or display device (e.g. lamp) can be
connected to the internal switching contact on the
J3 circuit board
connector (terminals A+A1,A2)
. Depending on the model of the
external device, different connection conditions must be complied
with (see
The condition for the switching function can be set by the [AUX Fct]
and [AUX time] parameters on the RoCon BF controller (see the op-
erating instructions for the controller).
Fig. 4-36
Connection of switching contact (AUX output)
The relays user for variant 2 (switched output > 15 W) must be suit-
able for a 100 % power-on time.
Connection terminals B+B1 are not occupied for these devices or
are available for additional functions.
J16 circuit board connector
A room thermostat (potential-free switching contact) can be connec-
ted to the
J16 (terminals 1+2)
on the circuit board connector (see
). A connected room thermostat has to be activated by
the [Room thermostat] parameter on the RoCon BF controller.
In "Heating" operating mode and during the active heating phases of
the time program, a closed switching contact causes a heat request.
This request has priority over the switching functions connected over
the J8 circuit board connector (exception: EBA switching contact).
Frost protection functions are also active when the switching contact
is open.
Terminals 3+4 are not occupied for these devices and are available
for additional functions.
INFORMATION
Further instructions and a detailed description can be
found in the "RoCon BF controller” documentation. It is in-
cluded in the scope of delivery of the GCU compact.
4.7.4
Connecting the RoCon OT1 outside
temperature sensor
▪ Choose a location at about one third of the building height (min-
imum distance from floor: 2 m) on the coldest side of the building
(north or north-east). Ensure that the location is not near any ex-
ternal heat sources (flues, air ducts), nor subject to direct solar ra-
diation.
▪ Place outside temperature sensors in such a way that the cable
exit points face downwards (prevents the ingress of humidity).
CAUTION
Laying the sensor and mains lines in parallel in a wiring
conduit can lead to major malfunctions during controlled
operation of the GCU compact.
▪ Always lay the sensor line separately.
INFORMATION
When the GCU compact is used
as master
in a CAN bus
system ("terminal function" for remote control of other data
bus devices), the outside temperature sensor RoCon OT1
must be connected
directly to
the controller RoCon BF
of
the master
and
not to the remotely controlled device
(mixer circuit module RoCon M1 or other heat generator).
1
Connect the outside temperature sensor to a twin-core sensor
line (minimum diameter
1 mm
2
).
2
Lay the sensor line to the GCU compact.
3
Connect the sensor line in the boiler control panel to the con-
nector of connecting terminals 7 and 8 of the
J8
12-pin sensor
connector (see
4
Connect the connector to the PCB control panel (
Fig. 4-37
Connect the J8 sensor connector to the PCB control
panel.
5
Close the control panel.
Summary of Contents for GCU compact Series
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