How much fuel is consumed when idling with the heater on for one hour?
3 Answers
When idling with the heater on for one hour, the car consumes approximately 4 liters of gasoline. Extended relevant information is as follows: 1. Idling with the air conditioner on is related to engine displacement. Generally, the larger the displacement, the higher the fuel consumption. 2. The engine's rotation mainly maintains the operation of the air conditioning compressor, water pump, oil pump, flywheel, etc. If the clutch is engaged at this time (without pressing the clutch pedal), the engine also needs to drive the gears of the transmission input shaft and other components. Therefore, engine idling consumes a significant amount of fuel. 3. When driving on the highway, try to avoid opening the windows too much, as when driving at speeds exceeding 80 km/h, most of the car's fuel consumption is used to overcome wind resistance. Opening the windows wide increases wind resistance, and using the air conditioner is actually more fuel-efficient than opening the windows wide.
I've been driving for over a decade and have plenty of experience with idling to run the heater. Actually, the heater itself doesn't consume much fuel since it uses the engine's waste heat. However, the engine idling does burn fuel - at least 1.5-3 liters per hour. My old 2.0L car was tested to burn 2.2 liters of fuel per hour when idling with heater on at -10°C in winter, which costs nearly 20 yuan at current fuel prices. Smaller displacement cars save a bit more, while larger engines consume more. Older cars especially those over five years old burn more fuel due to component wear reducing efficiency. To save fuel, I recommend turning on the heater only after the car starts moving, or at most idling for 20 minutes before shutting off.
It hurts my wallet just thinking about fuel consumption. An ordinary family car idling for an hour burns 1.8-2.5 liters of fuel, which is equivalent to thirty bucks literally going up in smoke. Although the heater doesn't consume extra fuel, idling the engine is just burning money. Last time I waited for my wife while she shopped at a gas station, idling with the heater on for forty minutes made the fuel gauge drop noticeably by one small segment. The most frustrating part is that my newly bought electric car saves me from this hassle since the engine doesn't even run. With fuel prices so high nowadays, I'd rather wear a thick down jacket or buy a hot drink from a convenience store while waiting, which is much more cost-effective than running the heater in the car.
