As the HVAC industry transitions to refrigerants with lower global warming potential (GWP), A2L refrigerants like R-454B are becoming more common. These refrigerants are classified as “mildly flammable” and require the installation of A2L leak detection sensors in many applications to ensure safety. While these sensors are essential for detecting actual refrigerant leaks, HVAC technicians […]

This tech tip is the final installment in our short series on using oscilloscopes to troubleshoot communicating systems. Imagine this scenario: you've got a refrigeration system acting up, and the comms network, whether it's LON or MOD-bus, seems a bit flaky. Let me introduce you to oscilloscopes—more specifically, a PC version called the PicoScope 2204A. […]

This tech tip about preventing heat illnesses covers information and resources from the Cleveland Clinic, the U.S. Centers for Disease Control and Prevention (CDC), the U.S. Occupational Safety and Health Administration (OSHA), and the National Oceanic and Atmospheric Administration (NOAA). HVAC School is NOT an official OSHA training resource, and although these safety tips are […]

In today’s podcast, Eric Mele and Bryan explain the planning, layout, and execution of HVAC projects. They mostly cover commercial ductwork but also touch on piping and some residential projects. Planning The first step is to review the construction plan WITH a site visit. It is best to see how a plan works within the […]

In this short podcast episode, Bryan and Eric Mele talk about re-tapping transformers for single-phase equipment in 208v applications. Most single-phase equipment can work for 230v or 208v, meaning that they can operate with low voltage. However, we typically see 208v in commercial buildings. The sine waves of 208v equipment are 120 degrees out of […]

In this podcast episode, Bryan and Eric Mele discuss the diagnosis and prevention of compressor overheating in HVAC and refrigeration. The main causes of compressor overheating are inadequate cooling back to the compressor, low charge, restrictions, and sometimes even poor suction line insulation. We want to keep the suction temperature low while maintaining appropriate superheat. […]