Automatic process and device for cleaning a heat exchanger for gaseous fluids

A device for periodically cleaning internal surfaces of an array of vertical channels arranged for heat exchange between a flow of gaseous fluid flowing within said channels and another fluid flowing outside said channels, the upper opened end of each said channel communicating with an upper chamber, comprising a resilient member mounted permanently within each of said channels along the channel length so as to be located in the gas flow near but out of contact with said internal surfaces during normal heat exchange operation;

• injection conduit means located in said upper chamber in registry with said opened end of at least some of said channels;
• and injection control means for producing an injection of compressed gas in a determined group of injection conduit means at determined time intervals into a corresponding determined group of said some channels for inducing into said corresponding channels a flow of gaseous fluid and causing said resilient member in said channel to vibrate and contact the inner surfaces of said corresponding channels at a multitude of locations therealong and scrap and loosen any deposits on said inner surfaces.