Heater system draws in fuel and air, which mix diesel fuel and burn to produce heat. Meanwhile, the blower of the parking heater
system sucks cold air, mainly comes from the outside environment through the air inlet pipe.
In winter, the windows of your car/vehicle are often icy or frosted which will block your view, and you may need to scrape the windscreen by your hands. Next, sitting on the cold seat, you have to drive your car/transportation with frozen hands in a freezing cabin.Just install a parking heater, all those problems will go away!