Net refrigeration effect (NRE) is the quantity of heat that each pound of the refrigerant absorbs in the refrigerated space to produce useful cooling. That’s a pretty vague definition. We know that it’s an amount of heat in processes that take place within the evaporator. Still, the phrase “useful cooling” seems rather broad. Even though […]

First, let's give proper credit. Most of the best practices and tools for diagnosing ECM and X13 motors come from Regal/Genteq and their site, thedealertoolbox.com, and their app, The Dealer Toolbelt. Your best bet is to follow the practices shown there and use their TECInspect diagnostic tool shown below. Here is the general process to […]

This article is an extension of HVAC School’s “How to Measure Gas Pressure” video. Additional input was provided by Jim Bergmann. Bubble test procedures and standards were provided by Honeywell. Links to source materials are available at the end of this article. If there’s one complaint that HVAC techs should never take lightly, it’s a […]