Commercial HVAC Tons per Square Foot (Sizing Guide)
Commercial HVAC sizing by square feet per ton, with planning figures for offices, retail, restaurants, warehouses, and server rooms — why internal gains dominate and why a block load calc is required.
Duct Size Chart: How to Match Duct Size to CFM
A round duct size chart by CFM, what a ductulator actually does, the friction-rate and velocity rules behind it, how to convert round to rectangular, and how to size supply vs return ducts.
Furnace and AC Replacement Cost (Replacing Both Together)
What it costs to replace a furnace and air conditioner together: combined price ranges by efficiency tier, why a matched system is worth it, the cost breakdown, and when to replace just one.
Heat Load & Cooling Load Calculation: How It Works
How an HVAC load calculation works — the heat-loss formula Q = U × A × ΔT, the sensible and latent parts of a cooling load, a worked residential example, and how to convert load to tonnage.
Will a Higher SEER Save You Money? The Real Math
How much a higher-SEER air conditioner actually saves on your bill, the formula linking SEER to annual cost, a cost-by-rating comparison, and the payback math that decides whether the upgrade is worth it.