Checking The Gas Valve; Electrical Resistance Of The Power Supply Cord; Checking The Gas Valve; Internal Electrical Resistance - Buderus Logamax plus GB162-80 kW Service Instructions Manual

7 Actions
section 111 Checking the gas valve;
electrical resistance of the power supply cord
 Switch off the power supply to the heating system, see
section 72.
 Open the boiler door as instructed in section 73.
 Remove the UBA 3 as instructed in section 82.
 Remove the cover from the connection tray, see section 114.
 Undo the plug or plugs of the gas valve supply cord as shown
in the illustration in section 109.
81-pin low-voltage connector
16-pin high-voltage connector
 Set the multimeter to "Measure resistance" [1].
 Check the power supply cord of the gas valve for breaks.
 The electrical resistance measured separately for every wire
Ω
must be approx. 0 [2]. Measure between the plug and the
black contacts (low-voltage connector pins 71 and 72) on the
UBA 3 mounting base [3].
 Check the power supply cord of the gas valve for internal
short circuiting. The electrical resistance, measured between
two random wires, must be infinite.
 Carry out a measurement to ground to make sure that there
is no short circuit between the gas valve and ground. The
electrical resistance between the gas valve cable and ground
must be infinite. See section 131.
 Attach the gas valve plug or plugs in reverse order of
removal.
 Install the lid on the connection tray in reverse order.
 Install the UBA 3 in reverse order of removal.
 Close the boiler door as instructed in section 77.
 Switch on the power supply to the heating system, see
section 79.
80
2
1
3
Logamax plus GB162-80 kW/100 kW - Subject to modifications resulting from technical improvements!
section 112 Checking the gas valve;
internal electrical resistance
 Switch off the power supply to the heating system, see
section 72.
 Open the boiler door as instructed in section 73.
3
 Disconnect the plug of the gas valve [1].
 Set the multimeter to "Measure resistance" [2].
 Check the internal electrical resistance of the left-hand coil of
the gas valve by measuring it. The electrical resistance of the
left-hand coil must be approximately 6
1
3
 Disconnect the plug of the gas valve [1].
 Set the multimeter to "Measure resistance" [2].
 Check the internal electrical resistance of the right-hand coil
of the gas valve by measuring it. The electrical resistance of
the right-hand coil must be approximately 75
 Attach the gas valve plug or plugs in reverse order of
removal.
 Close the boiler door as instructed in section 77.
 Switch on the power supply to the heating system, see
section 79.
1
approx. 6
2
Ω
[3].
approx. 75
2
Ω
[3].
Ω
Ω