Do you know how a solenoid valve works? Really? On the surface, I think we all understand how a solenoid valve works. The coil energizes, creating an electromagnet. That temporary magnetism lifts an iron plunger within the valve allowing refrigerant to flow. But is it really that simple? It turns out that the answer isn't […]

  I walked into a supply house the other day and looked at a “universal” expansion valve on the shelf. The friendly guy behind the counter saw me and walked over. After saying hello, he said: “That's a great valve; it's even balanced port.” Now, I am a bit of a troublemaker. I should have […]

Jesse Grandbois is one of the techs who reads the tech tips, and he wrote a few tips that he wanted to share on some gas furnace control basics. This tip is about the basic terminal designations on a typical 24v gas valve. Thanks, Jesse! Have you ever noticed the TH/TR terminal on a gas […]