Tech Tips

The temperature of the refrigerant in the evaporator coil can really help us with diagnostics, but we need to know the targets we’re aiming for if we want to get the most out of it as a troubleshooting tool. If we take the return air temperature and subtract 35 degrees from that number, we get […]

I've recently seen heated debates in different HVAC groups about whether it is okay to recharge a residential HVAC system with R22 without locating and repairing the leaks. I've had residential customers call me and complain about other companies telling them they must replace their system because it leaks. They've also stated that it is […]

Have you ever been tasked with installing the exhaust duct for a kitchen hood?  I have, and when doing so, I wondered how to size the duct run correctly. Since I had a basic understanding of how airflow works, I knew that there had to be a limit on the resistance the fan can handle; […]

This tech tip was submitted by Steve Rogers, the current president of The Energy Conservatory (TEC). Steve has been on the podcast several times in the past and is a valued contributor to HVAC School. Thanks, Steve! As summer approaches, HVAC technicians all over the US are preparing for those difficult conversations with occupants about […]

Over time, I’ve seen people use just about every type of temperature-measuring device in just about every location imaginable. From drilling tiny holes into rooftop unit panels to sticking a K-type wire into a piece of flex duct (I don’t remember why), I’ve done it all.  Coming up through the trade, I’ve been TOLD to […]

I recently read a tech tip by Matt Bruner about using the Manual D process. In the article, he designed a duct system for a small job using a ducted mini-split. One thing I noticed about his design was that the supply and return duct velocity was fairly low compared to the arbitrary 900-feet-per-minute supply […]

This article was written by Don Gillis, the current Technical Training Manager at Chemours. Don was also involved in a popular symposium session about A2L refrigerants with Jason Obrzut and Dr. Chuck Allgood, which you can now watch for free on our YouTube channel HERE. Thanks, Don! We all know that the change to A2L […]

In my second year in HVAC, I went out with a senior technician to install a supply duct for a bathroom in a house. While he ran the duct, I cut a hole in the plenum and attached the collar. He crawled back across the attic and very nicely told me that people don’t typically […]

I like processes. I especially like them in the HVAC profession because they give me confidence that I did the job correctly and save me time. When I’m following a process, I spend less time thinking about what I’m doing because my body and mind are trained by repetition. I particularly like processes that back-check […]