A heater including a cylindrical housing with an inlet end, an outlet end, and an axis extending between the inlet end and the outlet end. A combustion chamber is positioned at least partially within the cylindrical housing. A base is coupled to the cylindrical housing. A user interface is operable to control combustion within the combustion chamber. The axis is positioned between the base and the user interface.

A heating, ventilation, and air conditioning system includes a heating system. The heating system portion of the HVAC unit can comprise an array of heat exchanger tubes attached to a first side of a heat exchanger panel and a burner assembly attached to a second side of the heat exchanger panel. The burner assembly can comprise one or more tabs to facilitate installation and removal of the burner assembly within the HVAC system. The heat exchanger panel can comprise one or more slots that receive the one or more tabs of the burner assembly.

A heating, ventilation, and air conditioning system includes a heating system. The heating system portion of the HVAC unit can comprise an array of heat exchanger tubes attached to a first side of a heat exchanger panel and a burner assembly attached to a second side of the heat exchanger panel. The burner assembly can comprise one or more tabs to facilitate installation and removal of the burner assembly within the HVAC system. The heat exchanger panel can comprise one or more slots that receive the one or more tabs of the burner assembly.

A heater including a cylindrical housing with an inlet end, an outlet end, and an axis extending between the inlet end and the outlet end. A combustion chamber is positioned at least partially within the cylindrical housing. A base is coupled to the cylindrical housing. A user interface is operable to control combustion within the combustion chamber. The axis is positioned between the base and the user interface.