Do You Need to Turn on AC When Using the Heater in Winter?

[MadelynDella]

No, you don't need to turn on the AC because the car's heating system utilizes the engine's own heat to produce warm air for heating purposes. Here's the proper way to use the car heater: 1. When the engine has just started in winter, the coolant temperature is still low. Turning on the air conditioning at this point won't quickly warm up the cabin but will instead increase the engine's workload and delay its normal temperature rise. 2. After starting the car, wait approximately 8-15 minutes until the coolant reaches normal operating temperature (typically around 70°C), then you can turn on the heater. 3. There's no need to activate the AC switch when using the heater as this would engage the compressor (which provides cooling).