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Tech Tips:

One of the most common questions we get from techs is about using a voltmeter to diagnose a high voltage circuit. It's especially tricky when a tech is used to working on a low-voltage or 120V circuit, where there is a clear “hot” side of the circuit and a clear “grounded” side of the circuit. […]

Ohm My

One of the most common mistakes I hear techs make is confusing zero ohms with infinite ohms. The fuse above is showing near-zero ohms, which indicates a good electrical path with very little resistance. If there is a perfect path, it would have zero ohms (which isn't actually possible unless you happen to be […]

Something You May Want to Consider on Every Call

There are a few important things that I suggest checking on every service call to reduce callbacks and increase customer satisfaction. One of them that often gets missed is preventing wire rub-outs. One of my area managers and experienced tech Jesse Claerbout shot a video showing the simple step he takes to prevent major damage. […]

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Users with Tag #electrical

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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.

In this episode, Bryan sits down with compressor teardown specialist Ty Branaman for a deep dive into what really kills refrigeration and AC compressors. After some lighthearted banter, the conversation quickly turns technical: Ty has spent years cutting apart failed compressors on video, and he explains why that practice matters so much. As he puts it, he is “all about making the invisible visible” — once a technician actually sees what happened inside a dead compressor, vague explanations like “it just got old” stop holding up.

Bryan and Ty establish that a properly maintained compressor should essentially last forever, since it is a sealed system with no external contaminants — unlike an engine. The catch is that installation and service mistakes introduce the very contaminants that shorten its life. Copper plating tops Ty’s list of the most common findings: moisture combines with POE oil to form acid, which etches copper that then plates onto moving parts, thickening them and eventually causing hard starts that get mistaken for a “tired” compressor. They also trace how a shorted or seized compressor is usually the end result of an earlier root cause, not the cause itself.

The two work through the major categories of contamination one by one: solid debris from unswept lines and copper shavings left behind during deburring; moisture, which requires a proper pressure test, deep vacuum, and decay test to remove, plus heat to actually drive water molecules out; and non-condensable gases like oxygen and nitrogen, which throw off pressure readings and, with flammable A2L refrigerants, introduce real fire risk. Ty shares a memorable story about a compressor shell that ripped open after being left pressurized with nitrogen, and both discuss the surprisingly common problem of “wet” nitrogen and poorly maintained recovery tanks.

The conversation closes on flooded starts — a hazard Ty considers hugely overlooked — where migrated liquid refrigerant mixes with crankcase oil and violently flashes to vapor on startup, often shattering scroll plates. They cover practical prevention methods, including crankcase heaters, pump-down solenoids placed ahead of the metering device, and reduced refrigerant charges, before wrapping up with Ty’s quick field technique for cutting the top off a failed compressor to get an on-the-spot diagnosis rather than waiting on a full teardown back at the shop.

Topics Covered

Why compressors fail from external contamination rather than simply “wearing out”
Copper plating as the most frequently found problem inside failed compressors
Solid contaminants: dirt, copper shavings, and proper deburring technique
Moisture control: pressure testing, deep vacuum, decay testing, and heat-assisted evacuation
Wet nitrogen and poorly maintained recovery tanks
Oxygen and nitrogen contamination, including flammability risks with A2L refrigerants
Flooded starts, crankcase heaters, and pump-down solenoids
Superheat measured at the compressor versus at the evaporator outlet
Ty’s quick-cut technique for on-the-spot compressor diagnosis in the field

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Compressor Failures, What and Why w/ Ty

07/09/2026

Bryan Orr

Multi Position Valves and More – Short #293

07/07/2026

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