Older heat pump can’t keep up with winter weather

A little over five years ago, my husband and I moved down south. We bought a small home with a lovely view of a lake surrounded by palm trees. The house is heated and cooled with an older heat pump. The heat pump is extremely innovative in that the single unit handles both heating and cooling. It runs on electricity, and there’s no combustion process. Rather than burn fossil fuels to generate heat, the system moves existing heat from one place to another. In the summer, it pulls heat from inside the home and uses refrigerant to transfer it outdoors. No matter how hot the outdoor temperature, it keeps the home perfectly cool. The heat pump is also quite good at handling excess humidity. Despite the age of the heat pump, we’ve found it to be reliable and energy efficient. During the milder weather, the system draws from the ambient heat in the outdoor air, compresses it to a higher temperature and supplies it inside. In our local area, the outdoor temperature rarely drops below forty degrees. The heat pump has no problem keeping up with the needs of our little house. Unfortunately, every once in a while, we get hit with an unusual cold snap. When below freezing temperatures arrive, our ancient heat pump struggles. Modern heat pumps have become increasingly effective, no matter the weather. We’ve considered replacing our system but the cost of a new heat pump is astronomical. There’s typically only a few weeks per year that we’re faced with such severe weather. My husband and I bought a small electric heater that resembles a wood burning stove. It provides enough heat to make up for the inadequacies of the heat pump.