RESISTANCE DHW TEMPERATURE PROBE AND HARNESS

Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4

Set Multimeter to Resistance

Remove connector CN4 from the PCB

Measurement:

Measure the resistance between pin 5 (grey)
and pin 6 (grey) on connector CN4.

Resistances vary with temperature and should conform approximately to the table below:

Temperature Range (°C)	Resistance Range
0°C to 10°C	18.0kΩ - 28.0kΩ
10°C to 20°C	12.0kΩ - 18.0kΩ
20°C to 30°C	8.3kΩ - 12.0kΩ
30°C to 40°C	5.7kΩ - 8.3kΩ
40°C to 50°C	4.1kΩ - 5.7kΩ
50°C to 60°C	3.0kΩ - 4.1kΩ
60°C to 70°C	2.2kΩ - 3.0kΩ
70°C to 80°C	1.7kΩ - 2.2kΩ
80°C to 90°C	1.3kΩ - 1.7kΩ
90°C to 100°C	1.0kΩ - 1.3kΩ

Note: Clicking on the resistance table will switch between table and graph view.

Note.
On some PCB's the connector will be labelled as CN12 not CN4 and its orientation will differ, however the test points and expected results remain the same.