Tech Tips

This tech tip about traditional and desiccant dehumidification is based on a conversation with Nikki Krueger and David Schurk. Nikki is a longtime contributor to HVAC School and is a relatively frequent podcast guest and symposium speaker. David Schurk is the Director of Applied Engineering and National Sales Manager at Innovative Air Technologies. Nikki specializes […]

A while back, I had a tech who was having some trouble finding a 35 PSI (2.41 bar) make-on-fall pressure switch. One adjustable switch in the catalog said (SPDT), but he didn't quite understand what that meant. In that case, it means single-pole, double-throw, and the “double-throw” part means that the switch has terminals in both the […]

I remember it like it was yesterday. It was my first day of work as a trainee at my first technician job, just a wet-behind-the-ears kid fresh out of trade school. It was a Monday morning, and the technicians and I were standing in the dusty warehouse surrounded by stacks and stacks of brand new […]

Determining the proper size and orientation of return grilles, supply registers, and diffusers may seem like such a simple thing, but it's an area where confusion and mistakes are commonly made. First, let's define some terms. Return A return draws air into a return duct system with negative pressure compared to the space, usually via […]

There has been much written and many jokes made about the misdiagnosis of TXV (thermostatic expansion valves), and rightly so. This article on how to diagnose TXV failure will cut straight to the point to help those of you who may still need a bit of clarification, and hopefully, we will save the lives of […]

Disconnects walk the fine line of being HVAC or electrical, but the HVAC technician is allowed to repair and replace disconnects in most places. Even if you work at a place where it isn't allowed, finding problems is a diagnostic skill you will want to have, and checking disconnects is a good thing to do […]

One of the most common parts to fail on a single-phase HVAC system is the run capacitor, so much so that we sometimes refer to junior techs as “capacitor changers.” While capacitors may be easy to diagnose and replace, here are some facts many techs may not know: Capacitors Don't “Boost” the Voltage  A capacitor […]

Trying to wrap your head around HVAC can feel like a constant firehose of new info, right? Whether you're in class or on the job, there's just so much to soak up. And when you finally think you've got one thing down, BAM, here comes another concept. For me, remembering everything can be a real […]

Anytime we have a compressor failure, we can’t just pull out the bad compressor and drop a new one in. We have to put our detective hats on and find the culprit so that it doesn’t happen again. In many cases, acid is a prime suspect. Whenever there’s acid in the system, the next compressor […]