They draw around 15 amps or so. I tried one, eventually a 15 amp fuse lasted for a while, but the heat output sucked.
Return it, and pull the vent covers off of the output vents in your heater for a big jump in heat.
My oil line fix
My 100k stopped odometer fix
Brace for impact, I'm in a "modifying mood". Massive thread count inbound.