Tech Tips

We had a class with our refrigeration techs, and the topic of leaking and bypassing service “angle” valves and ball valves came up. One of the techs pointed out that most valves recommend loosening the top nut on ball valves and the packing nut on angle valves before turning the stem for maximum longevity of […]

As we have mentioned in several previous articles (such as this one HERE), many blended refrigerants have glide, which simply means they boil and condense over a range of temperatures instead of just one temperature. As an example, consider refrigerant R407c. It is a zeotropic blend, which means it has enough glide to make a […]

  Every contractor is different. I get that. We don't all need to do everything the same way or include the same services with repairs, but there are some “best practices” that can save you a lot of heartache before, during, and after you make a big repair. Catch it During Diagnosis Let's say you […]

DISCLAIMER: HVAC School is NOT an official OSHA safety training resource! Although we provide safety tips in good faith, our website is not a substitute for safety training from an authorized OSHA training source.   When most people think about respiratory devices, their minds probably jump to soldiers wearing gas masks in warfare, hazardous waste […]

I got this question via email (edited slightly for length): Some things I've done because I've been taught to do them yet I don't know why I do them. One of those things is putting a jumper between w1/e and w2. Sometimes, in the case of a Goodman for example, I've been taught to combine […]

Many of us understand that we need to get involved in local trades education to prepare students for fieldwork and get more people to consider careers in the trade. One of the ways contractors can support educators is by getting involved with local trade schools and industry organizations. We can do that by attending meetings […]

One of my most popular YouTube videos goes over how to adjust TXV superheat. It's a very simple little video that I did at my desk, and the other day I got this comment: “Good Video but I hate to say this BUT, with the title SCHOOL, why would you show the public an instructional […]

How many times have you looked at the bottom right-hand side of an evaporator coil and seen all sorts of rust, even on a fairly new coil? You may have noticed that many evaporator coils and even some condenser coils will start to corrode where the galvanized steel endplates touch the copper u-bends of the […]

Commissioning a system is critical anytime a technician makes any type of repair or alteration to an existing system. It’s also important if you’re working on a system you’ve never worked on before, and it’s a vital part of a new install start-up. Basically, commissioning systems is an everyday responsibility for technicians, which means everyone […]