COMPACT HIGH-EFFICIENT AIR HEATER

摘要

A compact high efficient air heater (10) providing improved comfort regulation. The air heater includes a cross-flow type heat exchanger (18) formed from a plurality of stacked corrugated plates (58a and 58b) which define a plurality of alternating flue gas passages and air passages and whi ch include a plurality of modified air passages which provide increased air flo w through the heat exchanger along the flue gas inlet side (66) whereby increased heat transfer along the flue gas inlet side is accomplished. The a ir heater also includes a plurality of bypass channels (72) which direct air fl ow across at least one surface of the combustion chamber (14) to remove heat fr om the combustion chamber housing, to lower the temperature of the flue gases entering the heat exchanger, and to reduce the temperature gradient at the a ir outlet side (64) of the heat exchanger.