Abstract: A heater includes a burner housing that houses burners for combusting a fuel and air mixture into heated gas. Heater tubes each extend from and return to the burner housing for radiating heat. The heater tubes each have an inlet end and an outlet end with the inlet ends in communication with the burners for receiving the heated gas from the burners. A collector box is disposed in the burner housing in communication with the outlet ends of the heater tubes for receiving the heated gas from the heater tubes. A fan is in communication with the collector box to move the heated gas from the burners to the collector box. The outlet ends of the heater tubes are adjacent each other at the burner housing and each of the inlet ends of the heater tubes are spaced in different directions from the outlet tubes at the burner housing.

Abstract: A heater includes a burner housing that houses burners for combusting a fuel and air mixture into heated gas. Heater tubes each extend from and return to the burner housing for radiating heat. The heater tubes each have an inlet end and an outlet end with the inlet ends in communication with the burners for receiving the heated gas from the burners. A collector box is disposed in the burner housing in communication with the outlet ends of the heater tubes for receiving the heated gas from the heater tubes. A fan is in communication with the collector box to move the heated gas from the burners to the collector box. The outlet ends of the heater tubes are adjacent each other at the burner housing and each of the inlet ends of the heater tubes are spaced in different directions from the outlet tubes at the burner housing.

Abstract: A heating assembly for variably heating ambient air within a building. The heating assembly includes an elongated heating conduit. There may also be a plurality of heating assemblies 20 interconnected to each other to form a heating system for the building. If a heating system is employed, then the plurality of heating conduits will be interconnected to each other in such a manner as to define a common exhaust. A burner is connected to the inlet of the heating conduit. A fuel regulator is connected to the burner for providing fuel to the burner at a low fuel pressure, which defines a low heating temperature, and a high fuel pressure, which defines a high heating temperature. A vacuum device is connected to the exhaust of the heating conduit or conduits for pulling the air into the inlet and through the heating conduit to provide a negative pressure within the heating conduit during the heating of the air.