System Burnout Cleanup Procedures Class

We cover the basics of burnout and dive into cleanout procedures. We also look at the Emerson-Copeland Bulletin AE24-1105 for some information inside manufacturer literature.You can read that bulletin at the following link: HERE.

Burnout is a type of compressor failure where there is electrical arcing. A short-circuit to ground or from winding to winding burns the oil and refrigerant in the compressor. Burning that oil and refrigerant results in acids, wax, and other nasty residues inside and around the failed compressor. (Keep in mind that compressors use POE oil nowadays. So, if you swap a compressor on a system with mineral oil, the replacement will likely come with POE oil.)

Burnout is especially common in cases where moisture remains in the system due to improper evacuation. So, pulling good vacuums is a preventative measure for burnout. Solid contaminants and mechanical failures may also lead to burnout. However, not all contaminants are related to burnout. Non-condensables also do NOT contribute to burnout.

Emerson recommends the filter-dryer cleaning procedure. Every time you open a system for service, replace the liquid line filter-dryer. (Make sure to use a bi-flow dryer for heat pumps. If you use Emerson dryers, Joe Shearer recommends using bi-flow dryers on heat pumps AND straight-cool systems.) Replace the suction dryers, too. Eric Mele recommends slightly oversizing the dryers.

Some sources may recommend using charcoal in HH dryers to eliminate wax. However, we generally prefer using EK dryers with the most desiccant and activated alumina.

You will also want to clean filters and screens. In many cases, you may straight-pipe the dryers from their previous locations and install them in new locations. Emerson also recommends using a moisture indicator or sight glass for the cleaning procedure. While that is a good practice, it is not always necessary, especially in residential applications.