What is typical root cause of defrost heaters burning out? I replaced heaters 2 years ago and it looks like they are out again. Can these " big resistors " be burned out if too much voltage is applied to them? How much voltage should I read when the defrost cycle is "on" ?
ANSWER Hi Mark. On your maytag model the defrost heaters have red or orange caps that the wire pass through on each end of the glass enclosure. The issue is that they upgraded to a different type of rubber end that seals against the glass and still remains flexible. The newer style are a gray color. Is it possible that you had replaced it with the older style? They are a fragile part. Since they are a dual type of element, the upper melting ice will drop off onto the top glass of the lower placed one- if- they are not properly clipped in place with the top of the element covered so the water drips on the metal cover first and off to the side missing the heater altogether. They may have been placed incorrectly - thus failing prematurely. The defrost timer part # 68233-3 passes the 120 vac to the defrost thermostat. As the thermostat is closed below 14°, it will pass the voltage (120 vac) to the heater. Usually the defrost closes the neutral side of the power. The 120 vac supply positive is at the other side of the heater awaiting the completed circuit (neutral feed). The Defrost thermostat is part # 52085-29. It may have sticky contacts and only feed a partial supply. of voltage starving the element. If you test the element and the heater they need to be a closed circuit or 0-ohms. In defrost ,the timer will give 120 vac on the orange wire feed to the thermostat and the brown wire to the heater. Thank You.
Answered by AppliancePartsPros.com | Wednesday, December 07, 2011