Reference tables
Look-up charts built from thermodynamics and stable constants — ton/BTU/kW, BTU per sq ft by climate zone, fuel energy content, SEER2↔EER, HSPF2↔COP, AFUE typicals, CFM/ton and ASHRAE 62.2 rates.
Cooling capacity: tons, BTU/h and kWConvert cooling capacity between tons, BTU per hour and kilowatts, with the airflow at 400 CFM/ton — the standard reference chart.Rule-of-thumb BTU per sq ft by climate zoneRule-of-thumb cooling and heating BTU per square foot by IECC climate zone — labeled estimates for a first-pass size, not a Manual J.Fuel energy content — the $/MMBTU denominatorsEnergy content per unit of each heating fuel (therm, propane gallon, oil gallon, kWh, cubic foot) — the stable denominators behind delivered $/MMBTU.SEER2 ↔ EER referenceApproximate EER for common SEER2 ratings using the documented SEER ≈ EER ÷ 0.9 relationship — for running-cost math.HSPF2 ↔ COP referenceApproximate COP for common HSPF2 ratings using HSPF ≈ COP × 3.412 — for heat-pump running-cost and comparison math.AFUE typical bands by system typeTypical annual fuel utilization efficiency (AFUE) bands by furnace type — labeled typicals for planning, not a spec sheet.Airflow reference: CFM per tonSupply airflow by cooling tonnage at the standard 400 CFM/ton (350–450 range) — for duct and register sizing.ASHRAE 62.2 whole-house ventilation ratesWhole-house mechanical ventilation CFM from ASHRAE 62.2 (0.03 × floor area + 7.5 × (bedrooms + 1)) for common homes.