What is Enthalpy?
Enthalpy is easy. It's just a state function that depends only on the prevailing equilibrium state identified by the system's internal energy, pressure, and volume. It is an extensive quantity. Simple. Like most things, the scientific definition is as clear as mud. In HVAC/R, we use enthalpy measurement to come up with the total heat […]
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What are Dry and Wet Contacts?
I was talking about dry contacts with one of my techs, and he looked at me like I had three heads—and one of them was on fire. So, I figured it would be good to cover the difference between wet and dry contacts in a tech tip. Basically, “dry” contacts are switches with no shared […]
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8 Tips for New Techs (So You Don’t Get Fired)
If you are new to the trade, I'd like to welcome you. Like many skilled trades, the HVAC/R trade has many opportunities and can help you make a good living. If you are young and new to the trade, we need you. We are grateful to have you. However, if you aren't thoughtful, you might […]
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Cooling Capacity Isn’t Always What it Seems
We all learned how to read the tonnage off of a model number within a few weeks of beginning in the trade. What you may (or may not) have learned is that just because something has an 036 in the model number, that does NOT mean it actually produces 36,000 BTU/hr. It doesn't reach the […]
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3 Bad Techs Who Don’t Know It
First, let's state the obvious and clear the air a bit. The photo above is SUPER CHEESY! But this story is about three bad techs who don't know it, so a photo of three models clearly posing in clean clothes makes as good of a proxy for a bad tech as anything else. First off, I'm […]
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5 Money Mistakes to Avoid in Service Business
Even though there will almost surely be a healthy demand for HVAC service businesses, any service business is still at risk of going under. Most of the trouble comes down to money mismanagement or misunderstanding. The good news is that the risks are avoidable with proper education and care. We aren’t accountants or lawyers, but […]
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Get (and Give) More From Remote Training
Most of the content in this article is based on Alex Meaney’s contribution to the HVAC School podcast in the October 2nd, 2020 episode: “How to Get The Most From Online Education,” which you can listen to HERE. Attending a class from your bedroom or home office sounds very convenient, right? That was probably what […]
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Nomenclature and How to Use It
Nomenclature on HVAC/R equipment is a sequence of numbers and letters a manufacturer uses to speak directly to the technician. Lots of initial upfront information is handed to the technician by the manufacturer the moment the technician reads the nomenclature in the model and serial numbers. So, how do we make sense of these seemingly […]
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Removing a Blower Motor
I’ve seen a lot of guys recently who reach for the motor puller tool first thing when attempting to remove a blower motor from a wheel/fan blade. Motor puller tools are an awesome backup tool when needed, but using a motor puller tool shouldn’t be the go-to method of removing a motor. The main issue […]
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