Electrical Tests For Electric Dryers Only; Electrical Tests For Electric And Gas Dryers - Frigidaire Dryer Servicing

Electrical Tests For Electric Dryers Only

High Limit Thermostat Cycle Time
Trip: Run the following test at room temperature. Set
the Time Dry cycle for 30 minutes and the heat selection
at maximum setting. Place a 100% exhaust block on the
exhaust pipe. The dryer door should be open for this
test and the door switch held closed by tape or similar
means. The thermostat must open (heater off) between
35 to 120 seconds.
Reset: When the exhaust block is removed and the
door closed (keep tape over door switch), the thermostat
must reset (heat on) within 120 seconds.
Thermal Limiter Trip Time
Run the following test at room temperature. Set the
Time Dry cycle for 30 minutes and the heat selection at
maximum setting. Place a 100% exhaust block on the
exhaust pipe. The dryer door should be open for this
test and the door switch held closed. The thermal
limiter should trip and shut off the heaters after 1 to
5 minutes of operation. To enable this test, the High
Limit Thermostat must be bypassed and NTC2 should be
removed from the heat duct.
NOTE
This test renders the thermal limiter inoperative, a new
thermal limiter must be installed after this test.
Drum Temperatures
The following tests should be run with an unrestricted
exhaust. The location of the thermal couple is to be
the square in the lint grill which is 12 squares left from
the right edge of the lint blade and (2) squares forward.
The tip should extend 1.25" into the air grill. Set the
dryer timer as needed for each test. The recordable
temperature is to be the maximum temperature follow-
ing the heater off of the 3rd cycle.
No load is to be used for following heat settings:
Heat Setting Thermistor Status
Max* Satisfied/Heater Off
Medium* Satisfied/Heater Off
Low* Satisfied/Heater Off
* Each opening temperature should be equal to or
higher than the opening temperature for the next lower
temperature setting.
Section 3 Electronic Control Testing
Electrical Tests For Electric and Gas
Dryers
Continuity
When measured by an Ohm meter, there should be
no more than .1 Ohms resistance between the termi-
nal block ground and any exposed metal dryer cabinet
component including control shafts and switches when
probed through or in any unpainted area.
Check continuity between motor frame and motor
support bracket using a continuity light. Test light must
illuminate when probing the motor frame with one end
of the test light and the motor bracket with the other.
If dryer fails continuity with a low voltage tester, check
continuity using 120 VAC.
Insulation Dielectric Strength
Disconnect ground link from the neutral of the terminal
block on the dryer. With dryer completely assembled
and with door closed, apply 120 VAC or more for one
second to the terminal block terminals or service cord.
Connect one probe to all three terminals and the other
probe to the back sheet. There shall be no more than
5mA of current during the one second test interval.
During the 1 second test, no drop in voltage below 120
VAC is permissible.
Motor Power
Audit - (power required after 20 seconds with no load,
motor CW direction, and no heat) 200 - 280 watts.
Line Test - (power required after 1-5 seconds with no
load, motor CW direction, and no heat) 210 - 290 Watts
Low Voltage Start
Dryer motor should start and operate at 100 volts (200
volts for 230 VAC, 50Hz dryers). The power will be
set to not dip below this voltage during any part of the
cycle. Increase voltage to allow for meter error and line
fluctuations. Test run with a 50 pound clothes load (25
pounds at 100% moisture) at "Maximum" heat setting.
Temperature °F
120 to 160
110 to 140
95 to 130
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