1994 Chevrolet Astro Owner's Manual - Page 177

Run your engine only as long as you must. This saves fuel. When you run the engine, make it go alittle faster than just idle. That is, push the accelerator slightly. This uses less fuel for the heat that you get and it keeps the battery charged. You will need a well-chargedbattery to restart the vehicle, and possibly for signaling later on with yourheadlights. Let the heater run for awhile. Then, shut the engineoff and close the window almost all the way to preserve the heat. Start the engine again and repeatthis only when youfeel really uncomfortable from the cold. But do it as little as possible. Preserve the fuel as long as you can. To help keep warm, you can getout of the vehicle and do some fairly vigorous exercises every half houror so until help comes. Towing a Trailer 4-23