Resistance heat and heat pumps
Though all PTACs cool a room the same way, there are two distinct ways a PTAC heats a room: via heat pump or via resistance heat.
Resistance (Electric) Heat:
Resistance heat units work by passing an electric current through wires to heat them. Resistance heat units require a smaller initial investment, but can result in higher energy costs when used for prolonged periods of time.
Heat pumps work in a similar manner to an air conditioner, except by reversing the cooling process to circulate warm air. Heat pumps use less energy than resistance heat models, but require a larger initial investment. All packaged terminal heat pumps also incorporate resistance heat technology that can help maintain room temperature when the outside temperature drops below the minimum operating threshold for a heat pump.
Heat pumps are suggested for cooler climates where the need for heat is greater; you’ll see a return on the initial higher investment in about a year. All climate zones within the U.S. will realize some energy cost savings by choosing a heat pump model, but the payback will vary by location.