Don Gillis Archives - HVAC School

Don Gillis

Company name: The Chemours Company

Position: Technical Trainer

Don Gillis is a technical trainer at Chemours. Prior to his work with Chemours, he was a training specialist and HVACR instructor for Copeland. He has over 30 years of experience in the industry, having been an installer, sales and service manager, and service technician. Don has written several tech tips for HVAC School and is a familiar face at the HVACR Training Symposium.

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Common Causes of Compressor Failure

This article was written by Don Gillis, the technical training manager at Chemours. Thanks, Don! Refrigerant compressors are essential components of air conditioning and refrigeration systems, as we all know. They work by compressing refrigerant vapor, which then flows through the system and changes state as pressure and temperature conditions rise and fall. Unfortunately, these […]

What Changes Will You Soon See With the Shift to A2L Refrigerants?

This article was written by Don Gillis, the current Technical Training Manager at Chemours. Don was also involved in a popular symposium session about A2L refrigerants with Jason Obrzut and Dr. Chuck Allgood, which you can now watch for free on our YouTube channel HERE. Thanks, Don! We all know that the change to A2L […]

Understanding “P” Traps in Refrigerant Lines

This article was written by Don Gillis with Chemours. Thanks, Don! There are 3 main reasons we use “P” or “U” traps: Assisting in oil return to the compressor Preventing oil accumulation in the evaporator Preventing liquid refrigerant or oil from entering the compressor while operating or during the off cycle Assisting in oil return […]

Flammable Refrigerant Update

Retrofitting Existing R-404A/R-507A Systems

This article was written by Don Gillis with Chemours. Thanks, Don! With the American Innovation Act (The AIM Act) in place and the reduction of the supply of hydrofluorocarbons (HFCs) in effect, the need to retrofit systems with lower global warming potential (GWP) refrigerants will become commonplace in the very near future. So, what does […]

How to Evacuate an AC system, Full Vacuum Procedure

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HVAC School – For Techs, By Techs

Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.

Licensed mechanical engineer Tony Amadio joins the podcast to talk about residential exhaust codes and best practices. He also put together a presentation about the topic, which you can view at https://hvacrschool.com/exhaust.

When choosing duct materials for residential exhaust, you will want to stick to sheet metal and mind the gauge; flex ductwork can easily be damaged and will rack up a high total equivalent length in a way that sheet metal will not.

Exhaust air should always discharge outdoors, not into an attic or crawl space, and that air needs to be replaced by air entering the conditioned space; makeup air is the air we draw in to replace the exhausted air, and we need appropriate undercuts to make sure we’re getting the right amount of makeup air.

Domestic cooking exhaust may also come in a few different varieties, each of which has different code requirements (with downdrafts needing much more CFM per ASHRAE). Range hood shape is also important for capturing as many particles as possible, but makeup air kits are usually unnecessary (and could be more of a hassle than they’re worth).

When it comes to bathroom exhaust, the CFM requirements differ between residential and light commercial, as well as intermittent and continuous exhaust. Steam generators may also be present, and they require extra consideration.

Tony and Bryan also cover: