01/29/2026
Here is the most likely reason for your heater struggling:
Extreme Cold Limits Capacity: When the outdoor temperature is 20°F , the temperature difference between inside and outside is vast. A furnace or heat pump may not have the capacity to maintain, say, 68°F if it was not designed for such extreme temperatures, especially if the home has poor insulation. If you have other alternatives to heat use it to help take some of the strain off the unit. Electric heaters, kerosene/propane heaters, wood/gas fire places etc…