Should the car AC be turned on for heating in winter?
2 Answers
Car AC should not be turned on for heating in winter. In summer, when cold air is needed, the AC switch should be activated. Car air conditioning cools by using a compressor to compress refrigerant into high-temperature, high-pressure gas, which is then cooled and delivered into the car via the blower. Heating relies on the engine's heat dissipation system. There is a small fan in the engine compartment that blows the heat collected by the cooling system into the car. The AC button (Air Conditioning) is mainly used for cooling and is more frequently used in summer. Its primary function is to activate the compressor for cooling, so there's no need to press the AC button when cooling is not required. In winter, when using the car's heating system to raise the temperature inside the car, the compressor is not needed. The heat generated by the engine operation is simply directed into the car's air conditioning system.
I've been driving for many years, and it's quite common for the heater not to work in winter, often not a major issue. The most frequent reason is that the engine hasn't warmed up yet; low coolant temperature means insufficient heat, especially on short trips—try waiting a few minutes after starting. Incorrect settings could also be the issue, like having the AC cooling mode on, which only blows cold air. You need to switch to heating or auto mode and turn up the temperature. Once, I had a faulty thermostat that wouldn't deliver heat, or low coolant—just a top-up fixed it. A clogged cabin air filter can also reduce airflow, which cleaning can resolve. Don't underestimate these issues; addressing them promptly can avoid costly repairs and ensure safe driving. Warming up the car before driving in winter is a good practice.
