What this tool does
Gives a preliminary room air conditioner size from floor area, sun exposure, occupancy, and whether it is a kitchen, using the ENERGY STAR purchase guidance for 8-foot ceilings.
How to use it
- Enter the room area in square feet.
- Choose the sun exposure: shaded, normal, or sunny.
- Enter the number of regular occupants.
- Enter 1 if it is a kitchen, then run it.
Worked example
200 sq ft, normal sun, two occupants, not a kitchen gives a base of 6,000 BTU/h and an adjusted figure of 6,000 BTU/h.
Frequently asked questions
- What if my ceiling is higher?
- The guidance assumes 8-foot ceilings. A higher ceiling means more volume and more capacity, so treat this as a floor and consult an installer.
- Does the BTU figure relate to my electricity bill?
- Not directly. BTU is cooling capacity; consumption depends on the efficiency rating. At the same BTU, a more efficient unit uses less power.
What this tool does not cover
Preliminary room-unit guidance that rounds up at band boundaries. Whole-building load design, duct sizing, and installation code review are out of scope.