Heating & Cooling Equipment by BTU Range

Use these quick links to shop by BTU capacity and category. If you haven’t calculated your needs yet, start with the simple BTU calculator or the advanced BTU calculator.

Updated for 2026 equipment models and Energy Star standards.

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On this page: Cooling · Heating · Comfort · Maintenance · Weatherization · Tools · Calculators · Resources · FAQ

Cooling equipment

Window air conditioners

Not sure what size? Use the window AC calculator.

Portable air conditioners

Not sure what size? Use the portable AC calculator.

Mini split systems (ductless)

Not sure what size? Use the mini split calculator.

Heating equipment

Heat pumps

Not sure what size? Use the heat pump calculator. Check for federal tax credits — heat pumps qualify for up to $2,000.

Space heaters

Not sure what size? Use the space heater calculator.

Garage heaters

Not sure what size? Use the garage heater calculator.

Radiant floor heating

Not sure what size? Use the radiant floor heating calculator.

For steady comfort, it’s usually better to seal drafts and heat loss than to oversize a portable heater. Need whole-home sizing? Use the furnace size calculator.

Comfort upgrades

Ceiling fans

Not sure what size? Use the ceiling fan calculator.

Dehumidifiers

Not sure what size? Use the dehumidifier calculator.

Maintenance & controls

Air filters (recurring purchase)

Find your size with the air filter size calculator. Replace 1″ filters every 1–3 months; 4″ filters every 6–9 months.

Smart thermostats

A smart thermostat can save 10–15% on heating/cooling. Estimate savings with the energy cost calculator.

Insulation & weatherization

Often the cheapest “BTU upgrade” is reducing heat gain and loss. These low-cost improvements can reduce your heating/cooling needs by 10–30% and often pay for themselves in a single season.

Use a thermal leak detector to find drafts before you seal them. For official guidance, see the Energy.gov weatherization guide.

Diagnostic tools & meters

These inexpensive tools help you diagnose comfort problems, verify equipment performance, and identify where you’re losing energy.

Size your equipment first

Use our free calculators to find the right BTU, wattage, or capacity before you buy.

Mini split · AC size (central) · Heat pump · Furnace size · Space heater · Garage heater · Radiant floor · Ceiling fan · Dehumidifier · Air filter · Grow room · SEER savings · EER to SEER2 · Energy cost

Services & resources

Frequently asked questions

What size HVAC equipment do I need?

Size depends on the room or home area, climate zone, insulation quality, and equipment type. As a rough starting point: window ACs need about 20 BTU per square foot, mini splits cover 400–600 sq ft per ton, and central AC systems need 1 ton per 400–600 sq ft depending on climate. Use the free BTU calculator for a precise recommendation before buying, or browse the sizing calculators above for each equipment category.

What is the difference between BTU and tons for HVAC?

BTU (British Thermal Unit) is the standard unit for measuring heating and cooling capacity. One ton of cooling equals 12,000 BTU per hour. So a 2-ton central AC delivers 24,000 BTU/hr, and a 3-ton system delivers 36,000 BTU/hr. Window ACs and portable ACs are rated in BTU; central AC and heat pumps are rated in tons. Mini splits are rated in both.

Should I buy a window AC, portable AC, or mini split?

Window ACs are the most energy-efficient single-room option and cost the least upfront ($150–$600). Portable ACs are easier to move and require no permanent installation, but are less efficient than window units. Mini splits are the most efficient option (SEER2 15–26), work for both heating and cooling, and have no duct losses — but cost more upfront ($700–$2,500+). Use the window AC, portable AC, or mini split calculator to size each option for your room.

What is the most energy-efficient heating and cooling system?

Mini split heat pumps are typically the most efficient residential option, with SEER2 ratings of 15–26 for cooling and HSPF2 ratings of 9–13 for heating. They move heat rather than generating it, delivering 2–4 units of heating or cooling energy per unit of electricity consumed. Central heat pump systems are slightly less efficient due to duct losses, but still outperform gas furnaces in mild to moderate climates (Zones 1–4). Use the EER to SEER2 converter and SEER savings calculator to compare specific models.

Do I need to get HVAC quotes for installation?

For central AC, heat pumps, furnaces, and whole-home mini split systems, professional installation is required. A qualified contractor should perform an ACCA Manual J load calculation before sizing equipment — not just match the old system's tonnage. Get free HVAC quotes from local contractors. Window ACs, portable ACs, and plug-in space heaters are DIY-friendly and require no installation quote.