Testing Dc Voltage From The Temperature Sensor - Travis Industries Deerfield Service & Troubleshooting Manual

Testing DC voltage from the Temperature Sensor

The temperature sensor functions by receiving voltage from the PCB and returning a smaller voltage signal back to the
PCB. The amount of voltage that the sensor sends back to the board is a direct relationship to the temperature at the
sensor (10mV = 1°Celsius). The temperature sensor can be checked for proper operation by testing the DC voltage at
the appropriate pins on the board. To test the temperature sensor follow the steps below:
1. Touch one lead to the left pin and the other to the right pin. You should read approximately 5VDC at this point.
The 5VDC is the voltage that the PCB is sending out to the sensor. If 5VDC is not present then replace the
board.
2. Touch one lead to the center pin and the other to the right pin. You should get a mV reading on your meter
that will vary based on the temperature at the sensor (See illustration and example below). 10mV = 1°Celsius.
Example:
1. You take a reading between the center pin and the right pin and get a reading of
210mV.
2. 10mV = 1°Celsius so divide the 210mV by 10mV and you get 21°Celsius
3. To convert Celsius to Fahrenheit you multiply the Celsius reading by 1.8 and then
add 32 to the total so:
21°C x 1.8 = 37.8
37.8 + 32 = 68.9°F
Temp. Sensor Pins
NOTE: The temperature reading is the temperature at the sensor, which is in close proximity to the stove, so it may read differently
than another thermometer somewhere else in the room. If you are trying to determine if the sensor is reading correctly you should
use another thermometer near the location of the stoves sensor to compare the reading.
NOTE: If the board is showing a reading of 32°F it would indicate a disconnected or grounded sensor.
If the board is showing a reading of around 140°F it would possibly indicate the 5VDC shorted on the sensor.
PCB
17602010 - 12/15/17
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Temp. Sensor Pins
10mV per
degree C
5VDC