I have a stupid question, I have an engine block heater on my 1025R. Besides plugging it in, how does it technically work, can it be plugged in all the time in a cold garage, does it heat to a specific temperature and shut off or does it continue to heat. Is it reliable, as in risk of fire over time. etc. etc. I got no info with it. This is the block heater not a dipstick type. Factory John deere. I know it heats the coolant but does it have a max temperature?