Electric heating unit for use in building - comprises three parallel glass plates with one outer member bearing thin copper film connected to power supply

摘要

The electrical heating element is intended for space heating in a building, and comprises a three-plate glass box-shaped unit, (12) with a front plate (14), rear plate (16) and intermediate plate (18) all of glass. The rear plate (16) is coated with an electrically conducting film (20) of resistive material typically copper to which edge strip electrodes are attached, these being connected one to earth and one to mains electric supply, through a rheostat. The intermediate plate (18) has one face coated with a reflective coating. The electrically conducting film is coated with an insulating lacquer, to provide protection to personnel. The interspaces (36,38) between the plates are filled with a low-conductivity gas, preferably one suppressing combustion.