Dexter Laundry T-350 Parts & Service Manual page 49

B. Manual Reset Over temperature Safety Thermostat-
thermostat is located on the right side of the burner housing as you view from the back of the
machine. It is just above the gas valve and covered by a guard with a small access hole.
1. The manually resettable thermostat limits the operating temperature a dryer can reach should
some abnormal situation occur.
2. Should the thermostat be tripped, the tumbler will cease to heat until the thermostat is reset.
Once the dryer cools, the thermostat may be reset by inserting a pencil or stick through the
opening in the thermostat cover.
REMOVAL: To remove either the hi-limit thermostat on the rear of the burner housing or the
over-temperature thermostat on the right side of the burner housing, remove the mounting
screws holding its respective guard. Next, remove the terminal of each wires attached to the
thermostat. Lastly, remove the mounting screws holding the thermostat to the burner.
Pressure Regulator Adjustment
Use the following procedure whenever it is necessary to check the pressure regulator setting.
NOTE:
Any adjustment of the pressure regulator must be made with a manometer attached at the
plug in the main burner manifold.
1. Shut off the gas supply to the dryer.
2. Remove the 1/8" pipe plug from the end of the main burner manifold.
3. Attach a manometer to the manifold end.
4. Remove the pressure regulator cover screw on the gas valve.
5. Open the shutoff valve, and operate the dryer.
6. Adjust the pressure for a manometer reading of 3.5" water column gas pressure. (11.0" for L.P.)
NOTE:
The main burners must be operating when adjusting the pressure regulator.
7. Shut off the gas supply to the dryer. Remove the manometer and install the 1/8" pipe plug in the
manifold.
8. Open the shut off valve, start the dryer and check for gas leaks while the burners are ignited.
Heat Sensor
This unit takes the place of the regulating thermostat on a mechanical timer dryer. The Heat Sensor
is a thermistor. The way these work is fairly simple. As the temperature goes up, the resistance in the
thermistor (heat sensor) goes down. As the temperature drops, the resistance in the thermistor (heat
sensor) goes up.
Electronic Control Removal
Unlock the retaining lock in the control assembly. Slide the control out of the machine holding the control
by the metal tray. There is enough wire length to allow removing the control tray from the machine before
disconnecting the wires.
Temperature Sensor Testing
If either tumbler display shows an "F1" or "F2", that is an indication of possible temperature sensor
problems for that tumbler. Before replacing a sensor, check the wires and connections of the sensor
for damage. The sensor lead wires are very small and care should be used in routing and connecting
them. The sensors are located under the tumblers and may be viewed by removing the lint screen. The
temperature sensor should have 40,000 ohms resistance at room temperature if okay.
The second hi-limit
Part # 8533-104-001 1/18
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