There is a lot of misunderstanding about the HSO (hard shut-off) or “non-bleed” TXV (thermostat expansion valve) and what makes it shut off, why it exists, and how it “magically” opens. Once you understand the forces inside the valve, it is quite simple, obvious, and sadly devoid of any magic. The Three Forces  The TXV […]

This article was written by my good buddy, Bill Frisbie. Bill is a service manager and crack technician at AirFx, a Trane dealer in lovely Inverness, Florida. Thanks, Bill! One of the most intimidating things in the field is to walk up to a piece of equipment that you have either never worked on or […]

This article is written by one of the smartest guys I know online, Neil Comparetto. Thanks, Neil! Recently, I posted a question in the HVAC School Group on Facebook that went like this: “When designing a residential duct system, what friction rate do you use?” As of writing this, only one answer was correct according […]