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Tech Tips:

Confirming Liquid Levels with a Little Thermodynamics

Maintaining the correct vapor-liquid refrigerant balance is crucial for air conditioning and refrigeration system performance. Longer line sets hold more refrigerant, which increases the risk of liquid accumulating in the suction line or entering the compressor during off-cycles. Heat pumps are one common application that requires additional measures. Refrigerant flow reverses during heating, turning the […]

Third Law of Thermodynamics

When someone says there is no such thing as “cold,” only the absence of heat, you can point out that while cold is the absence of heat… absolute zero is the definition of COLD. The third law of thermodynamics addresses the absence of heat and what that means for entropy. It implies that absolute zero […]

First Law of Thermodynamics

The first law of thermodynamics is an extension of the law of energy conservation. The latter states that energy can be neither created nor destroyed but converts from one form to another. Thermodynamics is the study of heat’s relationship with mechanical work, and it establishes heat as a form of energy that can be neither […]

The Basics of Moving Heat (Thermodynamics)

In this episode of HVAC School, Bryan talks to some apprentices about basic thermodynamics. That is the fancy scientific way of saying that we're moving heat. The way we think of “hot” and “cold” is relative to our comfort. However, the scientific concepts of “hot” and “cold” are very different from our relative understandings of those […]

Preparing Non-Techs for a Southern Winter

Central Florida techs know the Southern winter all too well. Let's face it. It doesn't get super cold here regularly, but when it does, EVERYONE FREAKS. We get an abundance of service calls for unpleasant but not truly problematic conditions when people use their heaters. When people first turn on their heat, they can get […]

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HVAC School – For Techs, By Techs

Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.

In this episode from the 6th Annual HVACR Training Symposium, Brynn Cooksey, a home performance contractor from Michigan and technical training business owner, reveals how indoor air quality (IAQ) testing transformed his contracting business from a commodity service into a profitable specialty. Cooksey shares his proven methodology for turning IAQ into an “instant profit center” by implementing systematic testing on every service call.

Cooksey opens with a striking reality check: according to the EPA, Americans spend 90% of their time indoors, yet indoor air quality is 2-5 times worse than outdoor air. This presents a massive opportunity for HVAC contractors, as he explains that consumers are already spending $10 billion annually on air quality products at big box stores – but they’re treating symptoms rather than addressing root causes. His approach involves educating contractors on how to position themselves as the solution providers rather than letting customers self-diagnose with retail products.

The presentation dives deep into six critical IAQ parameters that every contractor should measure: particles (especially dangerous PM 2.5), volatile organic compounds (VOCs), carbon dioxide, carbon monoxide, humidity, and temperature. Cooksey emphasizes his “test in, implement solution, test out” methodology, demonstrating how this systematic approach not only ensures customer satisfaction but also provides concrete proof of value delivered. He shares real-world examples, including a dramatic case where routine IAQ testing during a water heater service call revealed a cracked heat exchanger that could have been life-threatening.

The episode concludes with extensive coverage of ventilation strategies, which Cooksey calls the “silver bullet” for IAQ improvement. He walks through the differences between supply-only, exhaust-only, and balanced ventilation systems, strongly advocating for Energy Recovery Ventilators (ERVs) as the optimal solution. His practical approach includes using DOE’s free REDCalc tool for proper ventilation sizing and emphasizes the importance of controlled ventilation over relying on natural air leakage – debunking the myth that “houses need to breathe.”

Topics Covered

The IAQ Business Case: How testing indoor air quality on every service call creates new revenue streams and differentiates contractors in a commoditized market
Six Critical IAQ Parameters: Detailed explanation of particles (PM 2.5), VOCs, carbon dioxide, carbon monoxide, humidity, and temperature – what they are, how to measure them, and health impacts
Systematic Testing Methodology: The “test in, implement solution, test out” approach that provides measurable results and customer proof of value
Particle Control Strategies: Source control, enhanced filtration (MERV 13-16), duct cleaning benefits, and duct sealing with Aeroseal technology
Chemical and VOC Management: Understanding formaldehyde and benzene sources, proper storage techniques, and why PCO devices aren’t recommended
Carbon Monoxide Detection: The life-saving importance of testing every home, understanding chronic vs. acute exposure, and why standard CO detectors aren’t sufficient
Ventilation as the Silver Bullet: Comprehensive coverage of supply-only, exhaust-only, and balanced ventilation strategies, with strong emphasis on ERV systems
Practical Implementation Tools: Using DOE’s REDCalc tool for ventilation sizing, integrating IAQ testing into service calls, and customer communication strategies
Real-World Case Studies: Multiple examples of IAQ testing uncovering dangerous conditions, from cracked heat exchangers to improper combustion appliance installation
Building Science Integration: How IAQ testing leads to broader building performance improvements, including duct sealing, insulation, and equipment sizing corrections

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Search Episodes

IAQ for the HVAC Technician w/ Brynn Cooksey

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