In this episode, Brad Cooper — second-generation HVAC technician, educator at Arkansas State University-Beebe (ASUBB), and CMHE-certified professional with HVAC Excellence — breaks down geothermal systems for everyday HVAC technicians. Brad brings a grounded, no-hype perspective to a technology that has long intimidated many in the trade. His central message is simple: if you already understand heat pumps and air conditioning, you already have most of the knowledge you need to service geothermal units. The only real difference, as Brad explains, is swapping air for water, a fan for a pump, and a condenser for two heat exchangers.
Brad opens with a compelling real-world story: a customer with two malfunctioning geothermal units called a company for help, but because the technicians were unfamiliar with geothermal systems, they replaced both units with air-to-air equipment — costing the customer $25,000 and stripping them of the significant efficiency benefits geothermal provides. This kind of outcome is exactly what Brad wants to prevent. He urges technicians not to shy away from geothermal work the way past generations were told to avoid flex duct or mobile homes, but instead to approach these systems with the same confidence and diagnostic mindset they bring to any HVAC call.
A major portion of the episode is devoted to practical diagnostics — specifically, how to use a pressure probe and a temperature probe on the water side to calculate GPM flow, BTU output, and system efficiency using a straightforward chart. Brad walks listeners through the math: a gallon of water weighs 8.34 pounds, multiplied by flow rate and delta T, gives you a reliable BTU reading — all without expensive equipment. He also covers the flush cart, the one specialized tool you'll eventually need for water-side work, and explains that most geothermal calls don't require it at all — the majority of failures are standard heat pump issues like bad capacitors, clogged drain lines, or faulty thermostats.
Brad closes with an encouraging, community-minded message: you don't need to go it alone. He encourages technicians to build a network of mentors — someone like a "Paul and a Barnabas" — who can guide them through unfamiliar territory in the field. He also highlights key industry resources, including IGSHPA (International Ground Source Heat Pump Association) for training and certification, GeoFlow for parts and materials, and his brother's company, EDGE Geo Supply, for tools and field training. Brad himself offers his personal phone number and email for anyone with questions, reinforcing that the geothermal community is accessible and willing to help.
Topics Covered
• Brad's background as a second-generation HVAC tech and his role at ASUBB and HVAC School
• Why geothermal systems intimidate technicians — and why they shouldn't
• The core analogy: air-to-air vs. geothermal (air → water, fan → pump, condenser → two heat exchangers)
• A $25,000 cautionary tale: replacing working geo units out of fear and unfamiliarity
• Geothermal efficiency: constant EER ratings vs. seasonal SEER ratings and why seasons don't affect geo performance
• BTU fundamentals: what a BTU is and how to calculate BTU output on the water side
• Tonnage review: 1 ton = 12,000 BTUs per hour, melting a ton of ice in 24 hours
• Water weight and flow math: 8.34 lbs/gallon, calculating GPM and BTUs with delta T
• Using a two-probe setup (pressure + temperature) and a field chart to diagnose water-side performance
• The flush cart: what it is, when you need it, and why most jobs won't require it
• Common heat pump-side failures in geo units: capacitors, low-pressure switches, evaporator coils, bad thermostats
• Common water-side failures: bad pump, low water, dirty water, frozen loop field
• How antifreeze/glycol affects heating load and BTU output — and when to add it
• Responding to frozen loop fields during extreme cold events (ice storms in Arkansas and Texas)
• Humidity control advantages of geothermal in high-humidity climates vs. high-efficiency air-to-air units
• Selecting the right system: geo isn't for every home or every situation
• Open-loop options: pulling water from lakes or rivers and utility company incentives
• Closed-loop installation considerations: drilling costs, lot size, and buried line depths
• Building a mentor network for field support (the "Paul and Barnabas" principle)
• Industry resources: IGSHPA for training and certification, GeoFlow, and Edge Geo Supply
Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.
Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.
Subscribe to our podcast on your iPhone or Android.
Subscribe to our YouTube channel.
Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.