RESISTANCE DRY FIRE THERMISTOR AND HARNESS AT TEMPERATURE

Set Appliance State:

Set Multimeter to Resistance

DHW Demand

Run the Appliance Until the Burner shuts down

Gas On

WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure

Mains Power On

Measurement:

Isolate Mains Power to appliance as per TOPs P4

Disconnect the connector to the dry fire and primary sensors.
Measure the Resistance between the two yellow wires.
The resistance varies with temperature and should conform to the table opposite.

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Temperature Range (°C)	Resistance Range
0°C to 10°C	20.0kΩ - 34.0kΩ
10°C to 20°C	13.0kΩ - 20.0kΩ
20°C to 30°C	8.0kΩ - 13.0kΩ
30°C to 40°C	5.3kΩ - 8.0kΩ
40°C to 50°C	3.5kΩ - 5.3kΩ
50°C to 60°C	2.4kΩ - 3.5kΩ
60°C to 70°C	1.7kΩ - 2.4kΩ
70°C to 80°C	1.2kΩ - 1.7kΩ
80°C to 90°C	900Ω - 1.2kΩ
90°C to 100°C	700Ω - 900Ω

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