Expert guides, diagnostic tools, and industry insights for HVAC professionals. Interactive calculators included.
Master the two most critical measurements in HVAC diagnostics. This guide breaks down the math, the meaning, and what the numbers tell you about system health — with a free interactive calculator.
The TXV is one of the most misdiagnosed components in HVAC. This guide covers the three failure modes — stuck open, stuck closed, and hunting — with the exact pressure readings and symptoms you'll see in the field.
🧮 Interactive CalculatorThe best HVAC system in the world can't overcome bad ductwork. This guide covers the fundamentals of duct sizing — how much air you need, how to know if you're getting it, and what happens when you're not.
🧮 Interactive CalculatorDelta T is the temperature difference between your supply and return air — the simplest indicator of whether your HVAC system is actually doing its job. Here's what your numbers mean and what to do when they're wrong.
A failing capacitor is one of the most common HVAC service calls — and one of the most preventable. Learn the signs of degradation, how to test properly, and why catching it early saves compressors.