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HVAC Running Cost Calculator

Estimate what heating and cooling cost per day and month.

Inputs

Inputs and assumptions

Typical values: central AC 3500W, window AC 1200W, heat pump 2500W, furnace fan 800W, electric furnace 10000W, space heater 1500W.

Run hours per day

Days

Compressor cycles; oversized units run fewer full-load hours.

DOE: 7-10% per 8h of 7-10F setback.

Rate

Result

Annualized cost
$1,199.52
Cost per full-load hour
$0.60
Cost for period
$99.96
Energy for period
588.0 kWh
Screening tool. Verify your utility tariff and equipment specs before deciding.

Frequently asked questions

What drives HVAC running cost?

System watts or BTU with SEER rating, thermostat setpoint, duty cycle, and local rate. Heating and cooling together are roughly half the US home bill.

How does SEER affect cost?

Doubling SEER roughly halves cooling energy for the same output. Compare nameplate SEER before replacing.

What thermostat setting saves most?

Each degree closer to outdoor temperature cuts runtime several percent. Programmable setbacks of 7 to 10 degrees for 8 hours save about 10 percent annually.

When should I replace the system?

Past 12 to 15 years, or when repair exceeds a third of replacement cost with rising bills, replacement usually wins.

Related calculators

Guides

01 HVAC and Lighting Efficiency That Pays: Costs, Savings, and Payback 02 How to Read Your Electric Bill: Charges, Rates, and Meter Readings

Workspace

Every result shows its math: your inputs, the formula, the numbers.

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