RESISTANCE THERMISTOR HEAT EXCHANGER / FLUE AND HARNESS

Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4

Set Multimeter to Resistance

Remove connector X6 from the PCB

Measurement:

Measure the resistance between pins 4 and 5 (blue and brown) on connector X6.

fr optimax he plus 38 c con x6 off pcb.gif

Note:
It can be difficult to test on these connectors, ensure a good connection is made, often it can be easier to test on the metal strip on the side of the connector.

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

Temperature Range (°C)	Resistance Range
0°C to 10°C	19.0kΩ - 30.0kΩ
10°C to 20°C	12.0kΩ - 19.0kΩ
20°C to 30°C	8.2kΩ - 12.0kΩ
30°C to 40°C	5.6kΩ - 8.2kΩ
40°C to 50°C	3.9kΩ - 5.6kΩ
50°C to 60°C	2.8kΩ - 3.9kΩ
60°C to 70°C	2.0kΩ - 2.8kΩ
70°C to 80°C	1.5kΩ - 2.0kΩ
80°C to 90°C	1.2kΩ - 1.5kΩ
90°C to 100°C	900Ω - 1.2kΩ

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