Dedicated Dehumidifier vs. Electric Reheat Dehumidification – Who Ya Got?
This tech tip was written by Tim De Stasio. He originally published it on his website, which you can visit HERE. Thanks, Tim! In March of 2024, I set out to better understand the cost of ownership and return on investment for two dehumidification strategies: a dedicated dehumidifier versus using electric reheat dehumidification from my […]
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The Misunderstood Lockout Relay
Educators love lockout relays, and we also love pretending you will still see them out in the field all the time. Sometimes, I have to look myself in the mirror in the morning and sadly repeat, “Lockout relays are dead.” I have to say it several times before the reality sinks in. Before I get […]
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HH vs. EK Filter-Driers: Technical and Field Comparison
When we think of HVAC system components, the big four come to mind: evaporator, compressor, condenser, and metering device. However, there are several accessories that keep the HVAC system working as intended, and the filter-drier is one we cannot ignore. Filter-driers protect HVAC/R systems by removing moisture, acids, and debris from refrigerant. In typical residential […]
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ECM, VFD, and Inverter – What’s the Difference?
Ever since Nikola Tesla invented the modern induction motor, we have been struggling with varying the speed of motors efficiently and reliably. The trouble in the HVAC industry is that there are several different types of technologies in play, and they can easily get confused. ECM (Electronically Commutated Motor) In residential and light commercial HVAC, […]
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Work Vehicle Entropy
Have you ever noticed that the more you're required to speed up to get all your work done in a day, the more the cleanliness of your work vehicle suffers? Some techs won't clean their vans, no matter how slow or busy the schedule gets, but most of us prefer a clean and organized vehicle. […]
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What Should My Superheat Be?
  The most common—and often most frustrating—questions that trainers and senior techs get asked sound something like this: “What should my ______ be?” or “My _____ is at ______. Does that sound right?” Usually, when the conversation is over, both the senior and junior techs walk away feeling frustrated because the junior tech just wanted […]
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This is Not a Soft Start
I used to call PTCR devices a "Soft Start". I was wrong.
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3 Ways to Reduce Compression Ratio in a Heat Pump
We’ve talked about compression ratio a lot over the years. Compression ratio is the number you get when you divide the absolute head pressure (PSIG + 14.7) by the absolute suction pressure (PSIG + 14.7). It measures the efficiency of a compressor, and lower numbers indicate that the compressor is moving more refrigerant while consuming […]
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Best Practices to Conserve A2L Refrigerants in a Shortage
If you own your HVAC company or are involved in management, you may have realized that our industry is currently facing a shortage of new A2L refrigerants, particularly R-454B and R-32.  Our own company has faced limited availability and long lead times, mainly due to supply chain disruptions and the increased demand now that our […]
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