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
Understanding Triple Evacuation
The triple evacuation is meant to be a means of dehydrating refrigerant tubing in a system that has high water content before refrigerant is introduced. This was and i...
Read more →
Can you Braze Mini-Split systems instead of Flaring them?
I have been asked, “Can we braze mini-split systems instead of flaring them?”. The answer, technically, is yes. The only question is in a warranty situation, will the ...
Read more →
Determining the Cause of a Liquid Line Restriction Problem!
First of all, a liquid line restriction problem can be confirmed by measuring the following before the evaporator coil freezes: Low Vapor Saturated Temp, High Superhea...
Read more →
Measuring a Liquid Line Restriction Problem!
The metering device is a purposeful restriction in the liquid line prior to the evaporator. The metering device is needed to lower the pressure of the liquid refrigera...
Read more →
Troubleshooting an Air Conditioning System with a Frozen Evaporator
When arriving on-site to a frozen evaporator coil and suction line on an air conditioner, you should be aware that at least one of the three following problems exist: ...
Read more →
Should I Check the Refrigerant Charge with Superheat or Subcooling?
If the outdoor unit has a single speed or two speed compressor running in second speed and the unit is not a Micro-channel coil, then Total Superheat or Subcooling can...
Read more →Electronics, in plain language.
Occasional notes on components, circuits and projects worth building. No hype, unsubscribe anytime.
We never share your email.
Read it at your own bench first.
Then decide.
30-day money-back guarantee, free shipping