Can you heat with an AC in winter?
When the heating mode works efficiently and when a heat pump is better — practical energy and cost view.
"AC won't replace heating in winter" is a 10–15-year-old myth in Georgia. Today — an inverter AC is a competitive alternative to a gas boiler, especially in the Tbilisi climate.
When the heating mode works efficiently
Inverter AC in heating mode is efficient when outdoor temperature is above −7°C. In Tbilisi this covers 95% of the year. In peak cold (Jan–Feb) efficiency drops to 60–70% — still COP > 2.5, cheaper than electric heating.
What is COP
COP = heat output / energy input. COP 4 = 1 kWh in gives 4 kWh of heat. Normal electric heater = COP 1.0. Inverter AC in mild conditions = COP 4–5.
So energy bill is 4–5× lower for heating with inverter AC vs a plain electric convector.
When a heat pump is better
Heat pump = dedicated heating system. Efficient down to −25°C with COP 4–5 even in cold periods. Fully replaces a gas boiler — heating + DHW from one system.
Choice depends on heated area and functionality. <100 m² apartment — 1–2 inverter AC units suffice. 100+ m², DHW, radiator heating — M-Thermal Arctic heat pump.