Why is it important to turn on space heater?

You may find a space heater in electric motors and switchboards. Crankcase heaters installed on small engines and compressors of all sizes.

Keeping those heaters on is required because:

1. During the equipment idle time, the moisture will accumulate on internal surfaces as they cool down. Moisture will contaminate the oil in crancase. In the case of the electric motor or switchboard, accumulated moisture will lower the insulation resistance and may lead to the equipment damage.
2. Warm oil has less viscosity which eases the startup of the equipment and reduces wear.