Abstract: A small lightweight auxiliary power plant including an engine, electrical alternator, water pump, air conditioning compressor and a heat exchanger is mounted at a convenient location on the tractor of a truck or other large vehicle. The main engine of the truck operates the existing truck air conditioning and heating system in a normal manner when the main engine is running. When the main engine of the truck is not operating and the smaller engine of the auxiliary power plant is operating, the truck air conditioning and heating system is operated by the auxiliary power plant. The heat exchanger of the auxiliary power plant then utilizes the heat of exhaust gases generated by the auxiliary power plant engine to warm the truck engine during the time it is not operating so that easy starting of the truck engine is made possible even in very cold weather. The exhaust gases from the auxiliary engine are also utilized to heat the lubricating oil of the main engine.

Abstract: A small lightweight auxiliary power plant including an engine, electrical alternator, water pump, air conditioning compressor and a heat exchanger is mounted at a convenient location on the tractor of a truck or other large vehicle. The main engine of the truck operates the existing truck air conditioning and heating system in a normal manner when the main engine is running. When the main engine of the truck is not operating and the smaller engine of the auxiliary power plant is operating, the truck air conditioning and heating system is operated by the auxiliary power plant. The heat exchanger of the auxiliary power plant then utilizes the heat of exhaust gases generated by the auxiliary power plant engine to warm the truck engine during the time it is not operating so that easy starting of the truck engine is made possible even in very cold regions. The electrical alternator of the auxiliary power plant supplies electrical power for the truck electrical system when the truck engine is not running.