6
Controller and electronic components
Installation and operating instructions
43
Gas Combi Unit
Floor-standing gas condensing boiler with integrated heat storage
008.1543899_02 – 04/2019 – EN
6.3.1
Replacing the inflow temperature sensor /
return flow temperature sensor and
pressure sensor
DANGER: RISK OF BURNING
There is a danger of scalding from heating water.
Sensors are connected directly to the pressurised heating
water.
▪ Before removal of the sensors, close the ball cocks on
the boiler inflow and boiler return flow, and depressurise
the system with the KFE cock.
WARNING
Use of an unauthorised temperature sensor causes the
safety and control functions to malfunction.
▪ Replacement parts must at least satisfy the technical re-
quirements defined by the manufacturer. This is the
case, for example, with original spare parts.
1
Remove the protective cover (see
2
Remove the upper panelling of the heat cell (see
).
3
Disconnect the connector from the sensor being replaced
(
, item 2).
4
Unscrew the sensor being replaced with an open-ended spanner
WAF 15.
5
Screw in the new sensor and connect the cable and connector.
▪ The plug connectors are shape-coded. Do not force the con-
nector.
▪
Pay attention to the stipulated tightening torque (see
6.3.2
Replacing the internal mixer sensor for
heating support
The internal mixer sensor t
V2
for the "ISM" heating support function is
fitted underneath the thermal insulation of the hydraulic line compon-
ents.
1
Remove the protective cover (see
2
Remove the thermal insulation (see
3
Fold open the front panel of the controller housing
(see
). Remove the plug from connection J8 and dis-
connect the sensor cable.
4
Pull the internal mixer sensor t
V2
on the cable out of the sensor
5
Insert a new mixer sensor into the sensor thermowell and secure
in this position with a rubber plug. Guide the cable into the con-
troller housing, connect to terminals 5 and 6 of PCB plug J8 and
insert the plug connector.
▪ The plug connectors are shape-coded. Do not force the plug
connector.
▪
Observe the specified tightening torque (see
Fig. 6-4
Replace the internal mixer sensor
1
Sensor thermowell for internal mixer sensor t
V2
6.3.3
Changing the storage tank temperature
sensor
The storage tank temperature sensor is connected directly to con-
nection terminals 9 and 10 of the 12-pin
J8
sensor plug on the boiler
control panel (see
INFORMATION
For further information on installing the storage tank tem-
perature sensor, see the "Storage tank temperature
sensor" installation instructions.
1
Open the boiler control panel and disconnect the
J8
connector
from the PCB control panel (see
2
Pull out the sensor from the sensor immersion sleeve on the hot
water storage tank.
3
Bend the pressing springs on the new sensor and push the new
sensor into the sensor immersion sleeve. The insertion depth is
marked on the hot water storage tank by a coloured marking de-
pending on the storage tank type.
4
Connect the sensor cable to the connector on connection termin-
als 9 and 10 of the
J8
12-pin sensor plug.
5
Connect the connector to the PCB control panel and close the
boiler control panel. Make sure there is sufficient tension relief
on the sensor cable.
Fig. 6-5
Replace the storage tank temperature sensor
Summary of Contents for GCU compact Series
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