A Practical Guide To AC Tonnage
AC tonnage describes cooling capacity, not machine weight. One ton removes about 12,000 BTU per hour. A correct estimate helps rooms cool faster, but it also protects wires, breakers, and energy budgets. Small units run continuously. Large units short cycle and remove less humidity. Both problems waste money and reduce comfort.
Why Electrical Planning Matters
Cooling equipment uses compressors, fans, controls, and starting current. The calculator converts the cooling load into input watts by using the selected EER value. Then it estimates running current from voltage and power factor. This is useful during early planning. Final circuit sizing should still follow local code, nameplate data, and a qualified electrician.
Main Load Factors
Room area is the base input. Ceiling height changes the air volume. More occupants add sensible and latent heat. Windows add solar gain. Poor insulation allows extra heat into the space. Hot climates increase the design load. Kitchens and equipment watts also raise the required capacity. The tool combines these values into one adjusted BTU estimate.
How To Read Results
The BTU result shows the estimated cooling demand. Tons show the matching cooling capacity. The suggested standard size rounds upward to a common half ton. This avoids choosing a unit that is too small. The electrical section shows estimated input watts, running amps, and a planning breaker size. These numbers are estimates, not final permit values.
Using The Chart
The chart compares the base load, adjustment load, and final load. This makes hidden heat gains easier to see. A large adjustment load may mean the room has sun exposure, poor insulation, many people, or high internal equipment heat. Adjust the inputs and submit again. This helps compare different design choices.
Best Practice Tips
Measure the room carefully. Count regular occupants, not rare guests. Use the real voltage and power factor when known. Pick a realistic EER for the chosen unit. Improve insulation and shading before increasing tonnage. Better building conditions can reduce unit size, wiring load, and long term energy cost. Document assumptions clearly. Save reports for project records, client reviews, maintenance planning, and future equipment comparisons after layout changes later.