You can leave it on all night, use a timer, or get up early and give it two to four hours. It won't hurt anything, won't cost but a few pennies, and will help the engine start more easily. Less wear and tear on the engine is always good.

If you have a trickle charger, put it on the battery overnight. A fully charged battery is always a help in starting an engine. The waste heat from the charging process also keeps the battery a little warmer so it works better. (Cold batteries lose some of their capacity.)

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970