IDEAL Logic Code Combi ES26 Installation And Servicing page 55

80 aLTERNa TINg 'F' aND '5' - RETURN ThERMIsTOR FaULT
Remove the Return Thermistor from the CH Return
Pipe and disconnect the wires.
Check the resistance using a suitable multimeter
connected across the thermistor's terminal pins.
C expect
At 25 o
At 60 C expect
o
At 85
o C expect
Is the Thermistor value correct?
Is there continuity between the PCB and the Thermistor?
81 aLTERNa TINg 'F' aND '6' - OUTsIDE sENsOR F aULT
Is the wiring securely connected at both the boiler and
Outside Sensor?
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
C expect
o
At 15
C expect
o
At 30
Is the Outside Sensor value correct?
Is the wiring securely connected between the
incoming terminal block boiler connection of the
Outside Sensor and the PCB?
Note. Boiler must be reset to recognise the sensor after the removal.
Ideal Logic Code Combi ES -
FaULT FINDINg
9,700 - 10,300 Ohms
2,400 - 2,600 Ohms
1,000 - 1,100 Ohms
YES
YES
31,000 - 35,000 Ohms
15,000 - 16,500 Ohms
7,700 - 8,500 Ohms
YES
Installation and Servicing
NO
Fit a new Thermistor
NO
Check and replace wiring as necessary
YES
Replace PCB
NO
Securely connect the wiring at both the
boiler and Outside Sensor
Fit a new Outside Sensor and reset after
NO
powering up.
Securely connect the wiring at the Terminal
NO
Block and the PCB and now reset
Replace PCB
YES
55