Fuel-fired, radiant heater

A fuel-fired, radiant heater comprising a fuel-fired radiant;

• a combustion chamber housing the radiant and having a wall providing an outwardly open port closed by a thin panel highly transmissive of infrared radiation from the radiant and spaced therebelow, the combustion chamber having an outlet port to permit escape of combustion product gases;
• a plenum, means for establishing a continuous pressure differential between the plenum and the combustion chamber with the pressure in the former greater than that in the latter;
• means providing an air flow passage from the plenum to the combustion chamber and configured to provide, and to continuously replenish, a pool of cooling air against and along the panel to cool the same and to prevent impingement thereon of hot combustion product gases;
• and means conveying air from the plenum to the radiant for use as combustion air.

A fuel-fired, radiant heater, comprising:

• a. a downwardly oriented, fuel-fired radiant;
• b. a generally parallelepiped shaped combustion chamber housing the radiant and having top, side, end and bottom walls with the radiant nearer the top wall than the bottom wall, the radiant having generally horizontal dimensions which are at least half the inside horizontal dimensions of the combustion chamber, the lower wall being spaced below the radiant and having a generally downwardly open port closed by a generally horizontal, thin panel highly transmissive of infrared radiation, the panel having an inner surface confronting the radiant and the combustion chamber having an outlet port for exhaustion of combustion product gases;
• c. a powered blower to draw cooling air from the atmosphere and to discharge the air under superatmospheric pressure;
• d. a generally parallelepiped shaped plenum having a side wall common to it and the combustion chamber, the plenum having an inlet positioned to receive the air under superatmospheric pressure from the blower, the common side wall having an opening therein adjacent the inner surface of the radiation-transmissive panel and configured to direct cooling air into the combustion chamber in the vicinity of the panel to cool the latter, said cooling air settling above the panel in a thick, turbulent, constantly replenished barrier layer in contact with and preventing impingement of hot combustion product gases on the panel, the radiant including an air inlet protruding into the plenum to receive combustion air therefrom in cocurrent flow with the cooling air.

A fuel-fired, radiant heater, comprising

• a plenum, and means for continuously supplying the plenum with air under superatmospheric pressure;
• a plurality of generally downwardly oriented, fuel-fired radiants, and means supplying air for use as combustion air from the plenum to each of the radiants;
• a combustion chamber housing the radiants and having a lower wall providing a generally downwardly open port closed by a thin panel highly transmissive of infrared radiation and having an inner surface confronting the downwardly oriented radiants;
• the combustion chamber having an outlet port for discharge of combustion product gases therefrom, and the combustion chamber further having a wall in common with the plenum, the common wall having an air flow duct therethrough and configured to provide a constantly replenished pool of cooling air above the panel to cool the same and to prevent impingement thereon of hot combustion product gases.