20° ΔT (Delta T), A Lazy Rule of Thumb
What should the delta T (ΔT) be? What do you mean!? 20 degrees, of course! We are referring to the air temperature drop across an air handling unit or evaporator coil in cooling mode. Actually, depending on who you ask, the answer will range between 18-22 degrees Fahrenheit. Heck, I’ve heard some insist that the […]
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System Oversizing & Independent Consulting w/ Genry Garcia
In this episode I talk with tech, contractor and consultant Genry Garcia about his experiences in helping other contractors in South Florida.
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Solenoid Facts
Do you know how a solenoid valve works? Really? On the surface, I think we all understand how a solenoid valve works. The coil energizes, creating an electromagnet. That temporary magnetism lifts an iron plunger within the valve allowing refrigerant to flow. But is it really that simple? It turns out that the answer isn't […]
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500 BTUs per Person Per Hour?
I heard a great presentation by Ron Auvil on VAV systems, and it got me thinking… Can you size a commercial system/perform a block load by the number of occupants? Yes!  No, I'm just kidding. That's crazy talk. There is way more to it than that. However, in a commercial environment, while the building's perimeter […]
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Capacitors – Series and Parallel
Knowing how to combine capacitors in series and parallel properly is a great practical field skill to employ when you need to get a customer up and running, but you don't have the exact size. Increasing in size is easy. Just connect in parallel and add the two sizes together. For example, if you needed […]
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Can Manufacturers Specs Be a Crutch?
Bert and Bryan discuss the commonly repeated phrase “refer to manufacturers specs” and when it works and when it feels like a crutch.
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HVAC System Design & Load Calculation Course
Duct and system design are two of the BIGGEST needs among technicians, salespeople and contractors. Matt Milton has generously agreed to teach a small online mastermind class on design, load calculation, the math of the trade and much more. While this training may be at “no charge” it certainly isn't FREE. It will require a […]
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Short #47 – Solar
By request, Bryan talks some solar system basics
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