14
R-22GV
R-22GT
R-23GT
R-24GT
TEST PROCEDURES
HIGH VOLTAGES ARE PRESENT DURING THE COOK CYCLE, SO EXTREME CAUTION SHOULD
BE OBSERVED.
DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPONENTS
OR WIRING.
To test for an open filament, isolate the magnetron from the high voltage circuit. A continuity check across
the magnetron filament leads should indicate less than 1 ohm.
To test for a shorted magnetron, connect the ohmmeter leads between the magnetron filament leads and
chassis ground. This test should indicate an infinite resistance. If there is little or no resistance the
magnetron is grounded and must be replaced.
Power output of the magnetron can be measured by performing a water temperature rise test. This test
should only be used if above tests do not indicate a faulty magnetron and there is no defect in the following
components or wiring: silicon rectifier, high voltage capacitor and power transformer. This test will require
a 16 ounce (453cc) measuring cup and an accurate mercury thermometer or thermocouple type
temperature tester. For accurate results, the following procedure must be followed carefully:
1. Fill the measuring cup with 16 oz. (453cc) of tap water and measure the temperature of the water with
a thermometer or thermocouple temperature tester. Stir the thermometer or thermocouple through
the water until the temperature stabilizes. Record the temperature of the water.
2. Place the cup of water in the oven. Operate oven at 100 % POWER selecting more than 60 seconds
cook time. Allow the water to heat for 60 seconds, measuring with a stop watch, second hand of a
watch or the digital read-out countdown.
3. Remove the cup from the oven and again measure the temperature, making sure to stir the
thermometer or thermocouple through the water until the maximum temperature is recorded.
4. Subtract the cold water temperature from the hot water temperature. Refer to the chart below for the
normal temperature rise of each model. If the water temperatures are accurately measured and
tested for the required time period the test results will indicate if the magnetron tube has low power
output (low rise in water temperature) which would extend cooking time or high power output (high
rise in water temperature) which would reduce cooking time. Because cooking time can be adjusted
to compensate for power output, the magnetron tube assembly should be replaced only if the water
temperature rise test indicates a power output well beyond the normal limits. The test is only accurate
if the power supply line voltage is 208/230 volts for models R-23GT, R24GT and 120 volts for models
R-22GV, R-22GT and the oven cavity is clean.
Model
RF output
Normal temperature rise
Line voltage
R-22GV/22GT
1200W
36.5 - 67.9˚F (20.3 - 37.7˚C)
120V
R-23GT
1600W
46.6 - 86.6˚F (25.9 - 48.1˚C)
208V/230V
R-24GT
1800W
50.4 - 93.6˚F (28.0 - 52.0˚C)
208V/230V
PROCEDURE
LETTER
COMPONENT TEST
A
MAGNETRON ASSEMBLY TEST
B
POWER TRANSFORMER TEST
DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPONENTS
OR WIRING.
Disconnect the primary input terminals and the secondary output terminals, and measure the resistance
of the transformer with an ohmmeter. Check for continuity of the coils with an ohmmeter. On the R x 1
scale, the resistance of the filament coil should be approximately and the resistance of the high voltage
coil and primary coil should be as follows:
Model
Primary coil
High voltage coil
Part code
R-22GV/22GT
Approx. 0.42
Ω
Approx. 106
Ω
RTRN-A453WRE0
Approx. 0.86
Ω
(at 208V)
Approx. 65
Ω
RTRN-A454WRE0
R-23GT
Approx. 0.95
Ω
(at 230V)
Approx. 0.86
Ω
(at 208V)
Approx. 60
Ω
RTRN-A455WRE0
R-24GT
Approx. 0.95
Ω
(at 230V)
