Parking Heater (Auxiliary Heater)

Fuel-fired units burn a small amount of petrol or diesel from the tank and heat the coolant or the air. They can be started by timer, remote control or smartphone app. Some diesel cars use an auxiliary heater while driving because efficient engines produce little waste heat.

A small burner heats the coolant, which is pumped through the engine and heater core while the blower warms the cabin.

Never run a fuel-fired heater in a closed garage, because it produces exhaust gas. Heaters that are not used for months can fail to start; running them briefly in summer is often recommended by manufacturers.