1 The freezer time shown is for best quality only â foods kept constantly frozen at 0Â° F will keep safe indefinitely.  How long does baked ham last at room temperature? Bacteria grow rapidly at temperatures between 40 Â°F and 140 Â°F; baked ham should be discarded if left for more than 2 hours at room temperature.
Using this to calculate theoretical water-chilling capacity: 1 ton of refrigeration (12,000 BTUs per hour) will chill. 12,000 lbs. water/fish 1Â°F in 1 hour. Theoretically, then, a sample application to chill seawater and fish: 40 tons refrigeration (480,000 BTUs per hour) will chill. 120,000 lbs. water/fish 20Â°F in 5 hours.
Total, Sensible, and Latent Heat. The kind of Btu that makes up 12,000 Btu in a ton of cooling is called total heat. Total heat is made up of two kinds of heat: sensible and latent. In heating mode, all of the Btus are sensible heat. An 80,000 Btu output furnace should deliver 80,000 Btu into the duct system. Cooling removes two kinds of heat.