High Limit (Safety) Thermostat; Thermal Limiter; Heat System (Electric Dryers) - GE DBL333 Technical Service Manual

To check the control thermostat, remove the wiring
from the terminals. At room temperature, the
thermostat should have continuity between the
control thermostat terminals. To check the bias
heater, remove the wiring from the bias heater
terminals. Check the resistance between the bias
heater terminals. On an electric dryer, the resistance
should be 28K ohms. On a gas dryer, the resistance
should be 7K ohms.
To check for correct dryer temperatures, make
certain all panels are in place on the dryer and
remove the exhaust venting from the rear of the dryer.
Place a thermometer capable of reading at least
300°F in the end of the dryer duct. Set the timer
and allow the dryer to operate for 10 minutes with
an empty drum. Check the temperature immediately
after the thermostat has cycled off and the dryer
has reached its highest temperature. Depending
upon the cycle selected, the temperatures should
be between 165°F-195°F on a "High" setting and
between 150°F-180°F for a "Medium" setting. If the
complaint is long drying times and the temperatures
are correct, check for a restricted vent, too long a
vent run, or an excessive number of turns in the vent.

High Limit (Safety) Thermostat

The high limit (safety) thermostat is a single pole,
single throw switch wired in series with the control
thermostat. It is mounted towards the top of the
heater pan shield at the rear of the drum. If the
control thermostat should fail closed or an air
blockage occurs, raising the temperature in the
heater pan, the high limit thermostat opens the circuit
to the heat source.
THERMOSTAT
HIGH LIMIT
SAFETY
THERMAL
LIMITER

Thermal Limiter

The thermal limiter is wired in series with the drive
motor on all electric dryers. The purpose of the
thermal limiter is to shut down the dryer should the
control thermostat and the high limit thermostat fail
to open. Once the thermal limiter has opened, it
must be replaced. In addition, the condition that
caused it to open must be corrected. The most likely
cause would be an excessively long vent or a vent
with excessive turns. This is especially true if vinyl
or plastic venting was used.

Heat System (Electric Dryers)

The heater assembly is located behind the dryer
drum. Holes in the back of the drum allow heated
air to be drawn into the drum. The heating element
is an open coil heater, attached to a metal shroud
with ceramic standoffs. Check the heating element
HEATER
TERMINALS
11
HIGH LIMIT
SAFETY
THERMOSTAT