How to use the ice maker capacity calculator
The "lb per 24 hours" figure on an ice machine spec sheet is a rated value measured at the AHRI 810 standard condition: 70 F ambient air and 50 F potable water. Real kitchens and bars often run at 90 F air with 70 F supply water, and the same machine can then deliver close to 20 percent less ice. Sizing from the headline number alone is the usual reason ice runs out during a rush.
This calculator multiplies the rated capacity by an air and water temperature correction factor to estimate real expected output, converts that to an hourly rate, and then shows how long the machine needs to make the amount of ice you entered. The correction is a straight-line model of roughly 0.5 percent loss per degree F above the rating point for each of the two temperatures, capped at 110 percent, and it simplifies the trend shown in manufacturer capacity charts.
When the production time approaches 24 hours there is no cushion left, and ice demand is rarely spread evenly across the day. Check the storage bin capacity alongside daily volume, and confirm the final model against the manufacturer capacity chart for your actual air and water temperatures as well as the site water and drain conditions.
Frequently asked questions
Catalog ratings are measured at the AHRI 810 standard condition of 70 F ambient air and 50 F potable water. At 90 F air and 70 F water the condenser works harder and the incoming water carries more sensible heat, so the same machine can lose close to 20 percent of its output.
Yes, it means the machine must run nearly around the clock just to meet demand. Because ice use peaks at lunch and dinner, you should look at the next size up or a larger storage bin instead of running at the limit.