Chris for Model Number 110.74992301 Problem: Dry getting warm, but not hot. I have cleaned the vent system and dryer blower motor areas thoroughly. With temperature selector switch on highest setting, and dryer on timed setting, the ignitor glows and the flame ignites, but then the flame goes out shortly after ignition (maybe within 30 seconds or so). I have tested the thermal fuse, the flame sensor, the high limit thermostat and all have continuity. I have also checked the thermistor which has ~13.5K ohms resistance at ~64F. The thermistor also responds well by decreasing resistance with increasing temperature. I have not checked the moisture sensors, but I never use the automatic moisture sensing drying cycle, only the timed drying cycle. Wondering if this could be due to a problem with the temperature selector switch (WP3399643). I haven't been able to find any info or videos on what happens when this switch fails or how to test the integrity of this switch. Any ideas?
Answer Chris, the coils 279834 may need to be tested for a proper resistance rating as they can certainly cause this issue. The three-terminal coil should read 1,300-1,400 ohms across prongs 1&2, and 500-600 ohms across prongs 1&3. The two-terminal coil should read 1,000-1,300 ohms of resistance. The temperature selector can be tested for continuity when the dryer is unplugged. With the temperature selector set to high heat, contact 3 should have continuity to contact 5, and the contacts 1 and 2 should not have continuity to contact 4. If there is continuity between 1 and 4, or 2 and 4, then the temperature selector would need to be changed. If the selector tests good, then the heater relay WP3405281 will need to be tested for voltage from the temperature control WPW10116565. At the temperature control, the red probe of the multimeter would be placed at connection P3 pin 1 with the black probe placed at connection P3 pin 2. During operation, the voltage should read a continuous 48VDC. If the voltage stops, then the control has failed (unfortunately this control has been discontinued and is no longer available). If the voltage continues and everything else tests good, then the relay has failed and would need to be replaced. Read More... Answered by AppliancePartsPros.com | Thursday, January 9, 2020