block heater question

[BriGy86]

should I only leave it plugged in for a few hours or is it ok to have it plugged in when ever the car is parked?

 

[TitanDiddly]

It's fine to leave it plugged in all the time, though I wouldn't push it for more than a day. If your engine gets hot enough, the thermostat will pop open and the extra heat will be wasted out the radiator. Buy a timer and set it only to heat for the hour or two before you need to drive.

 

[woodie1]

I don't think a block heater is gonna warm the water enough to open the thermostat. I thought it was to keep the oil warm. Unless the owners manual says not to, I would leave it plugged in all the time. When my sister lived in ND she had a tank heater on her car which heats the water and everyone there left them plugged in 24/7.

 

[Demon-Xanth]

Even if the thermostat opens, the water pump isn't moving water through it.

 

[BriGy86]

from the owners manual

ENGINE BLOCK HEATER (IF EQUIPPED)
An engine block heater warms the engine coolant which aids in starting
and heater/defroster performance. Use of an engine block heater is
strongly recommended if you live in a region where temperatures reach
-10°F (-23°C) or below. For best results, plug the heater in at least three
hours before starting the vehicle. The heater can be plugged in the night
before starting the vehicle.
To reduce the risk of electrical shock, do not use your heater
with ungrounded electrical systems or two-pronged (cheater)
adapters.

maybe I'll just plug it in the night before.

 

[jagec]

Originally posted by: Demon-Xanth
Even if the thermostat opens, the water pump isn't moving water through it.

passive convection...but yeah, that's a pretty minor effect in this case. I can't imagine any block heaters would actually generate enough heat to open the thermostat anyway.