61
FAULT FINDINg
F
AUL
T FINDIN
g
F
AUL
T FINDIN
g
F
AUL
T FINDIN
g
F
AUL
T FINDIN
g
F
AUL
T FINDIN
g
Ideal Logic
+
Combi -
Installation and Servicing
87 OUTsIDE sENsOR FAULT - CONTACT INsTALLER
Disconnect the wires to the outside sensor.
Check the resistance using a suitable multimeter
connected across the Outside Sensor’s terminal pins.
At 0
o
C
expect
31,000 - 35,000
Ohms
At 15
o
C expect
15,000 - 16,500
Ohms
At 30
o
C expect
7,700 - 8,500
Ohms
Is the Outside Sensor value correct?
YES
Is the wiring securely connected between the
incoming terminal block boiler connection of the
Outside Sensor and the PCB?
Replace PCB
Fit a new Outside Sensor
NO
Securely connect the wiring at the
Terminal Block and the PCB
Is the wiring securely connected at both the boiler and
Outside Sensor?
YES
NO
Securely connect the wiring at both the
boiler and Outside Sensor
88 NO WATER FLOW ThERMIsTOR FAULT - CONTACT INsTALLER
Disconnect the wiring from the No Water Flow Thermistor
Check the resistance using a suitable multimeter connected
across the Thermistor’s terminal pins.
At 25
o
C expect
9,700 - 10,300
Ohms
At 60
o
C expect
2,400 - 2,600
Ohms
At 85
o
C expect
1,000 - 1,100
Ohms
Is the Thermistor value correct?
YES
Is the wiring securely connected to the low voltage 11 way
connector at the front left hand side of the PCB?
YES
Replace PCB
Fit a new Thermistor
NO
Securely connect the wiring to the PCB
Is the wiring securely connected to the No Water Flow
Thermistor (located in the top of the Heat Exchanger?)
YES
NO
Securely connect the wiring to the No
Water Flow Thermistor
NO
NO
YES
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