Intro Here are some images of Whirlpool Dryer Motor Relay contacts in different stages of use and failure. These are all images of the original Omron relays found on the dryer control boards. The first image shows new/unused Omron relay contacts. Notice the shiny protective finish as well as the concavity and convexity of the […]
Join The Tech Circuit, where the focus is: “Electronics for Field Techs”. We’ll collaborate about electronic troubleshooting, theory, schematics, circuits, and every other electric or electronics topic as it applies to Appliances, HVAC, and other Field-Tech disciplines. I started this group to help field technicians better understand the underlying electrical/electronic reasons for the things they […]
Infinite Switch Detailed Operation On electric ranges, the common infinite switch (or simmerstat) uses Pulse Width Modulation (PWM) to control the amount of power delivered to the cooktop burner ¹. Despite common misconceptions, PWM is not just reserved for DC voltage. It is simply a voltage (AC or DC) (also known as the carrier wave) […]
How to Test Diodes, Transistors, Triacs, MOSFETs and IGBTs with a Multimeter This page shows how to use a multimeter to test the most common semiconductors (diodes, transistors, etc), along with their associated readings and values. Readings outside of these ranges indicate likely failed components. Diodes, transistors, and other types of semiconductors are based on […]
Appliance Thermistor Lookup Tables Below are tables and graphs for thermistors commonly found in appliances. Feel free to bookmark this page for future reference! This web page will be revised as needed to add new and suggested thermistors. *CLICK HERE TO DONATE**CLICK HERE TO PURCHASE THE KLEIN CL800 MULTIMETER FOR APPLIANCE TECHNICIANS* Standard Range Sensor […]
Should Appliance and HVAC Technicians Learn about Electricity? If you work on appliances and HVAC systems, you will ultimately encounter symptoms caused by electrical and electronics failures. This does not just happen occasionally, but on a regular basis. You don’t want to be the technician that gets stuck because they cannot address such issues due […]
Electrolytic Capacitor Failure and How to Troubleshoot Failing aluminum electrolytic capacitors can have significantly adverse effects on electronic circuits. Most technicians have seen the tale-tell signs – bulging, chemical leaks, and even tops that have blown off. When they fail, the circuits that contain them no longer perform as designed – most often affecting power […]
Electric Range Common Failures, Bake Element, Broil Element, and Cooktop Element Resistances This online electronics cheat-sheet contains commonly needed electrical/electronics information for Electric Ranges. *CLICK HERE TO DONATE* Oven Sensor Resistance Chart Power Input Issues and Commons Symptoms Missing or weak L1 Missing or weak L2 Missing, weak, or floating Neutral Reversed L1 and Neutral […]
How to test Different Types of Diodes Testing diodes is primarily a matter of checking the forward and reverse bias voltages. LEDs have a higher forward bias than most diodes. The high-powered ones used for lighting usually cannot be tested with the diode check function on your meter nor with a simple resistance check. The […]
Loss of a 240v Voltage Leg of an Electric Dryer What happens when a loose connection at the junction box or terminal block on an electric dryer causes one of your line voltages to drop out? Here are the equivalent circuits and how to test for this loss. Figure 1 is a simplified equivalent circuit […]