did a patent search and found this
this is it
sealed steam portable electric heaterElectrically-powered portable space heater
US 4518847 A
Abstract
A portable electrically-powered space heater includes an electrically-powered boiler generating steam at subatmospheric pressure from a mixture of water and ethylene glycol that is circulated through a closed loop heat exchanger, portions of which comprise fin-tube radiators. The boiler is thermostatically controlled by a thermostat located in a chimney into which a downdraft of ambient air is drawn by a fan creating a forced-flow of air over the fin tubes. An automatic temperature-responsive time delay mechanism allows the boiler to get up to its operating temperature before the fan is actuated to draw air across the thermostat. The heater is further characterized by a novel design wherein a pair of upstanding heat exchangers are each housed in branches of a generally Y-shaped housing with a fan located in the stem-forming portion thereof effective to cooperate with the heat exchangers and the double-walled side panels alongside thereof to distribute a curtain of warm air over a 90° or better swath.
An additional object is the provision of a space heater of the type herein disclosed and includes heat exchange surfaces in the 250° F. range, yet all accessible exterior surfaces remain at all times no hotter than approximately 110° F. even though the heated air entering the environment will be much hotter
still don't know who mfg it, or the sales name
and it was water and glycol in the patent application
