Field Notes
Plain-language notes on components, circuits and how to read a schematic, written for people at the bench, not for a classroom.
Field Notes
R-22 and R-410A Operating Pressures, Charging, and Recovery Setup!
Operating pressures for R-22 and R-410A, plus the charging and recovery setup for each. See the P/T Chart.
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Checking the Charge of Air Conditioners Without Measuring Pressure!
How to assess a refrigerant charge without connecting gauges, and when that is appropriate.
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40 Vacuum Tips for HVACR Technicians! Avoid Frustration!
Forty practical tips for pulling a proper vacuum without the frustration.
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Is There an Easy Way to Tell if a Mini-Split Ductless Unit is Low on Refrigerant? (Quick Tip)
A quick tip for spotting a low charge on a ductless mini split.
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Clogged Liquid Line Filter Drier?
How to tell when a liquid line filter drier is restricted, and what it does to system readings.
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Troubleshooting an HVAC Control Board? How?
How to approach a control board before condemning it.
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