Gas Furnace Maintenance Procedure
This gas furnace maintenance procedure in this article was developed by Michael Housh. Michael is the owner of Housh Home Energy in Ohio. He regularly works on natural gas equipment and is an active contributor to the HVAC School Facebook group. Thanks, Michael! Gas-fired equipment has a different set of components than your typical straight-cool […]
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The Diagnosis Game (and Why Van Sleeping Bothers Me)
The Sleeper  The year was 2002, and I was 20 years old. I had a helper named Clay, and he was a really nice guy, probably 15 years my senior, already with streaks of grey in his hair with a way of making you feel at ease—so very at ease. OK, he was sleeping most […]
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The “Approach” Method of Charging and Condenser Efficiency
We have discussed many methods for checking a refrigerant charge without connecting gauges over the last few years. Recently, I've been thinking about the “approach” method of charging that many Lennox systems require. What is the Approach Method? The “approach” simply refers to the temperature difference between the liquid line leaving the condenser and the […]
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Retrofitting Existing R-404A/R-507A Systems
This article was written by Don Gillis with Chemours. Thanks, Don! With the American Innovation Act (The AIM Act) in place and the reduction of the supply of hydrofluorocarbons (HFCs) in effect, the need to retrofit systems with lower global warming potential (GWP) refrigerants will become commonplace in the very near future. So, what does […]
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Is it too cold to set the charge?
I've heard the phrase, “It's too cold to set the charge!” for as long as I've been in the trade. I've also heard some variations of, “We need to come back and set the charge,” or, “We need to come back to do XYZ [some other thing].” Granted, there are cases where you do actually […]
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A REALLY Loud Compressor
A while ago, I walked up on one of our managers who was talking to a junior tech diagnosing an intermittent controls issue on a pool heat pump. In the background, you could hear an EXTREMELY loud compressor. The junior tech had just been moving some wires around, and the next thing he knew, there […]
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4-20ma Control Basics
Back in the “good old days,” controls were all analog and mechanical; that simply means they acted in a directly connected and variable manner based on a change in force. Both pneumatic (air pressure) and hydraulic (fluid pressure) systems are examples of mechanical or analog controls. When the pressure increases or decreases on a particular […]
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Pool Heater Water Flow Issues
As you may already know, we work on pool heaters at Kalos as a way of opening ourselves up to some extra business during the winter. We find that it's a worthwhile line of work, and it may be something that other residential HVAC companies may want to consider doing. This tech tip by Bert […]
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Giving Thanks for the Hard Stuff
Trigger Warning: This article isn't specifically about air conditioning, and it includes a markedly Christian worldview. If you would prefer that I  “stick with the A/C stuff, preacher boy,” then this is one you should skip—or not. 🙂  Also, it's my birthday this week, so give me a pass.  Today, families all across the country […]
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