Replacing The Feed, Safety And Return Sensors - Buderus Logamax plus GB162-80 kW Service Instructions Manual

3
 Disconnect the DHW temperature sensor plug [1].
 Set the multimeter to "Measure resistance" [2].
 Check the DHW temperature sensor cable for breaks.
The electrical resistance measured separately for every wire
Ω
must be approx. 0 [3].
 Check the DHW temperature sensor cable for internal short
circuiting. The electrical resistance, measured between two
random wires, must be infinite.
 Measure the electrical resistance over the DHW temperature
sensor cable to ground. The electrical resistance must be infi-
nite for every individual wire.
2
1
 Set the multimeter to "Measure resistance" [1].
 Check the cable of the DHW temperature sensor between
the connection tray and the UBA 3 mounting base for breaks.
The electrical resistance measured separately for every wire
Ω
must be approx. 0 [2]. Measure between the connection
tray and the black contacts (low-voltage connector pins 63
and 64) on the UBA 3 mounting base [3].
Logamax plus GB162-80 kW/100 kW - Subject to modifications resulting from technical improvements!
3
3
81-pin low-voltage connector
16-pin high-voltage connector
WA FW EV
 Check the cable of the DHW temperature sensor between
the connection tray and the UBA 3 mounting base for internal
short circuiting. The electrical resistance, measured between
two random wires, must be infinite.
 Measure the electrical resistance over the DHW temperature
sensor cable to ground. The electrical resistance must be infi-
nite for every individual wire.
 Attach the relevant sensor plugs.
 Install the UBA 3 in reverse order of removal.
 Install the lid on the connection tray in reverse order.
 Close the boiler door in reverse order.
 Switch on the power supply to the heating system, see
section 79.
section 95

Replacing the feed, safety and return sensors

 Drain the boiler, see section 75.
2
 Switch off the power supply to the heating system, see
section 72.
 Open the boiler door as instructed in section 73.
A
CAUTION!
Note that some water may escape when the sensor is
removed. Keep a bucket and a cleaning rag ready.
 Disconnect the supply temperature sensor plug [1].
 Remove the clamp spring of the supply temperature sensor
3
by moving it in the direction indicated by the arrow [2].
 Remove the supply temperature sensor [3].
Actions 7
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