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
Testing Capacitors
An HVACR capacitor can be tested after turning the power off, disconnecting the wiring, and bleeding off any leftover voltage before testing. This can be done with a m...
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Target Superheat
To determine the Target Superheat for an air conditioning system with a fixed orifice (such as a piston or capillary tube) measure the indoor WB (wet bulb) temperature...
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The Total Weight Method
This charging method is used for systems that have no refrigerant. It is also used on new systems with a known amount of refrigerant in the outdoor unit. The goal is t...
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Superheat vs. Total Superheat
Superheat is the temperature increase of the vapor refrigerant from where it turns from the saturated state into a vapor at the evaporator coil until where it exits th...
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Heat Pump Pressure Switches
Pressure switches are typically installed in heat pumps and air conditioning systems to protect the compressor from a high pressure situation, to protect the compresso...
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Recovery Bottle Weight
In order to determine how much refrigerant can be added in a used recovery bottle, first the neck of the recovery bottle must be read. This will show the WC (water col...
Read more →Electronics, in plain language.
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