Formula
A refrigeration ton is defined as 12,000 BTU per hour:
tons = BTU/h / 12,000
The recommendation is the exact tons rounded up to the next 0.5. The BTU page starts from floor area and sun, not from a rating you already have.
Assumptions
- The BTU figure is a cooling capacity per hour.
- Equipment is sold in half-ton steps for this guide.
- The page does not add a climate factor.
Worked example
An 18,000 BTU per hour rating is 1.5 tons.
Input definitions
- Ton
- 12,000 BTU per hour of cooling, the refrigeration ton.
- Half ton
- The next catalog step at or above the exact tons.
Limitations
This is a planning estimate. The rate, sun hours, and losses are numbers you type. It is not a utility bill, a solar design, or a room-by-room load calculation.
Questions
Is 18,000 BTU exactly 1.5 tons?
Yes. 18,000 divided by 12,000 is 1.5, so the half-ton step does not move it.
How is this different from the BTU calculator?
That page multiplies floor area by 20, 25, or 30. This page starts from BTU you already have.