Relays can be used for many different control applications, including controlling fans, blowers, other relays, or contactors, valves, dampers, pumps, and much more. A 90-340 is a very common, versatile relay that many techs have on their truck. So, we will use it as an example. A relay is just a remotely controlled switch that […]

This article was written by Michael Housh and was inspired by a discussion that took place on the HVAC School Facebook group. If you are already a member of the group, you can look at the oversized furnace discussion yourself HERE. I'd like to give a special thanks to Michael and everyone who contributed to the conversation. […]

Replacing a compressor is expensive, time-consuming, and physically taxing. If we are replacing a compressor, I want us to be doggone sure we aren't going to be dealing with the same thing again, and this often includes a shiny new contactor and capacitor (on single-phase units). We received a comment recently that called out the […]