Calculator Inputs
Formula Used
SEER Formula:
SEER = Seasonal Cooling Output in BTU ÷ Seasonal Electric Energy in watt-hours
Estimated Running Watts:
Watts = Cooling Capacity BTU/h ÷ SEER
Seasonal Energy:
kWh = Cooling Capacity BTU/h × Seasonal Cooling Hours × Units ÷ SEER ÷ 1000
Seasonal Cost:
Cost = Seasonal kWh × Electricity Rate
Simple Payback:
Payback Years = Upgrade Cost ÷ Total Yearly Saving
How To Use This Calculator
- Enter the rated cooling capacity in BTU per hour.
- Enter the new air conditioner SEER rating.
- Add the old SEER rating to compare savings.
- Enter cooling hours per day and cooling days per season.
- Add your local electricity rate per kWh.
- Enter the number of matching units.
- Add upgrade cost and maintenance saving if needed.
- Press the calculate button to view results above the form.
- Use CSV or PDF buttons to save your calculation.
Example Data Table
| Capacity BTU/h | SEER | Hours/Day | Days | Rate | Estimated kWh | Estimated Cost |
|---|---|---|---|---|---|---|
| 24000 | 14 | 6 | 100 | 0.16 | 1028.57 | $164.57 |
| 36000 | 16 | 8 | 120 | 0.16 | 2160.00 | $345.60 |
| 48000 | 18 | 9 | 140 | 0.18 | 3360.00 | $604.80 |
Air Conditioner SEER Planning Guide
What SEER Means
SEER stands for Seasonal Energy Efficiency Ratio. It compares total cooling output with total electric energy used during a normal cooling season. A higher value means the unit delivers more cooling from each watt hour. This calculator turns that rating into seasonal power use, cost, and savings estimates.
Why Seasonal Hours Matter
A central air conditioner does not run at full load every minute. Weather, insulation, thermostat settings, duct condition, and shade all change real demand. For planning, the calculator uses cooling capacity, daily run hours, cooling days, and local electricity price. These entries create a practical seasonal estimate for one unit or several matching units.
Comparing Old And New Units
The result helps homeowners compare older equipment with a newer option. For example, a 36,000 BTU system rated at 14 SEER uses more seasonal energy than a similar system rated at 18 SEER. The difference becomes clearer when the same hours and power rate are applied. Estimated yearly savings can also support a simple payback review when an upgrade cost is entered.
Choosing Better Inputs
Use realistic inputs for better results. Review utility bills to estimate your local rate. Check the equipment nameplate for rated capacity. If capacity is shown in tons, multiply tons by 12,000 to get BTU per hour. Cooling hours should represent compressor run time, not the full time your thermostat stays on cooling mode.
Limits Of The Estimate
SEER calculations are helpful, but they are still estimates. A poorly installed high rated unit can waste energy through duct leaks, low airflow, wrong refrigerant charge, or oversizing. Regular filter changes, coil cleaning, sealed ducts, and proper thermostat schedules often improve real savings without replacing equipment.
Using Results For Decisions
The calculator also reports seasonal equivalent COP. This value converts the rating into a familiar performance indicator. It is useful for technical comparison, but SEER remains the main seasonal cooling label in many buyer discussions. When comparing quotes, consider comfort, warranty, noise, installer quality, and service support along with the rating. A balanced choice usually gives lower bills and steadier indoor comfort.
Saving Your Work
Keep records after each calculation. Save the CSV for later budget reviews. Use the PDF when sharing estimates with clients, landlords, or contractors. Recheck numbers after any thermostat, rate, insulation, or equipment change. Small updates can shift final annual costs over time too.
FAQs
What does SEER mean?
SEER means Seasonal Energy Efficiency Ratio. It measures cooling output compared with electrical energy used across a typical cooling season.
Is a higher SEER always better?
A higher SEER usually means lower energy use. However, comfort, correct sizing, installation quality, warranty, and repair cost also matter.
How do I find my air conditioner capacity?
Check the nameplate, model number, invoice, or equipment manual. One ton equals 12,000 BTU per hour.
Can this calculator compare old and new systems?
Yes. Enter the old SEER rating and new SEER rating. The tool estimates seasonal energy savings, cost savings, and payback.
What electricity rate should I enter?
Use your average cost per kWh from your utility bill. Include delivery charges if they are billed per kWh.
Why are my real bills different?
Actual bills depend on weather, insulation, duct leaks, thermostat settings, humidity, maintenance, and how often the compressor runs.
Does SEER show instant power draw?
No. SEER is a seasonal rating. This calculator estimates average running watts by dividing rated BTU per hour by SEER.
Can I save the results?
Yes. Use the CSV button for spreadsheet records. Use the PDF button for printable reports or sharing estimates.