When it comes to your home’s HVAC system, size definitely matters — and not in the cheeky way you think. A system that’s too small will leave you sweating through Houston summers, and a system that’s too big will short-cycle, waste energy, and create hot-cold swings that drive homeowners crazy. Let’s break down how to choose the right size HVAC system — and why guessing based on your old system is one of the biggest mistakes homeowners make.