Loren Faeth wrote:
The block heater puts out a steady output of heat. Most block heaters use
750 watts, and that can be translated into an average number of BTUs or
calories. After a period of time, the water temp in the engine reaches a
steady state (SS), where the heat input equals the heat loss. This SS temp
depends on several variables, primarily the surface area exposed to ambient
temp, the heat transfer properties of the conducting material (engine block
and head, primarily) the ambient temperature and the degree of wind. I
have often see the block heater, if left on overnight raise the coolant
temp enough that the needle is above the low peg when you start the
engine. A block heater on a car in a garage will normally produce a warmer
temp that what would be reached in a car outside in the breeze. In a tight
garage, the leaking heat could even raise the ambient temp in the garage a
degree or two.
Short answer, it could be 100 to 120 degrees F.
Mercedes block heaters are 400-500 Watt heaters. Under most conditions,
they raise the temp to between 30-40 deg C.
Marshall
--
Marshall Booth Ph.D.
Ass't Prof. (ret.)
Univ of Pittsburgh School of Medicine
[EMAIL PROTECTED]