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
What Components are in a Forced Air Gas Furnace? What do they Do?
Every major component inside a forced air gas furnace and the job each one does.
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Ductless Mini-Split Step-by-Step Installation
A full step by step ductless mini split installation. See also The Mini Split Book.
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The Benefits of Using an Ultrasonic Leak Detector to Find Refrigerant Leaks!
Why an ultrasonic leak detector finds leaks that other methods miss.
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Finding a Low Voltage Short Quickly, Step by Step!
A step by step method for isolating a short in a 24 volt control circuit.
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20 Causes of Low Indoor Airflow on Ducted HVAC Units!
Twenty things that restrict indoor airflow on a ducted system, and how to check each.
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Gas Furnace Electrical Safety Switch Testing!
Testing the electrical safety switches on a gas furnace.
Read more →Electronics, in plain language.
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