Sorry I missed this one. But working with espresso Machines and rewiring them from European to American power grid (And Australian 240/50hz btw) this is a simple matter of resistance heating. I does not matter the energy input (Amperage) or voltage input (120 or 240) as long as it is Alternating Current (VAC). The higher VAC will not cause the resistance heater rod to over heat, which would be impossible in a coolant filled, iron block, but always remember to use an earth grounded connection for the unit since your safety is most important as well as the sensitive electronics on board. I recommend if you are serious about using the coolant warmer, you will experience a rapid warming since the unit will use 10 Amps, regardless of the voltage, but never allow the cap to be removed from the coolant system while the unit is plugged in. Since the boiling point of water is lower than the admix of Ethylene Glycol, it might cause cavitation near the resistance rod, which would allow for the rod to overheat thus rendering it useless. If you haven't already rewired it, I can give you a heads up for wiring it to your power grid.
