| 摘要 |
<p>An under floor heating system for church halls, small churches, etc., uses large area flat electrical heating elements. These are supported on a layer of hard polystyrene foam housed inside a trough made of a PVC base attached to angle section PVC sides. The whole is covered by a heat distributor plate of asbestos cement. The load capacity of the foam material is about 3.5 kp/sq. cm. Between the heating elements and the distributor plate is a plastics foil sheet of e.g. polyethylene terephthalate. Between the distributor plate and the horizontal supporting flangle of the trough sides is a permanent elastic sealing strip. The conductor wires for the heating elements pass through holes through the angles forming the trough sides.</p> |
