Indirect fired heater with inline fuel heater

A system comprising:

• a fuel tank;
• an atomizing burner having a combustion chamber and nozzles that open into the combustion chamber;
• a supply line in fluid communication with the fuel tank and the nozzles of the burner, the supply line transporting a volume of fuel from the fuel tank to the nozzles;
• an inline heater provided in the supply line between the fuel tank and the atomizing burner, the inline heater comprising an electric heating element in thermal contact with the volume of fuel;
• a fuel filter provided in the supply line between the inline heater and the atomizing burner;
• a return line in fluid communication with the burner and the fuel tank, the return line returning a volume of unused fuel from the atomizing burner;
• and
• a manually operated valve provided in the return line between the burner and the fuel tank and having an inlet connected to the return line and first and second outlets fluidically coupled to the fuel tank and directly to an inlet of the inline heater, respectively, the valve being switchable to selectively couple the inlet to only the first outlet or the second outlet;
• wherein the valve is configured to either purge air from the burner via the first outlet, or return at least half of the volume of fuel transported in the supply line via the second outlet, independent of operating temperature.

A method of preheating a fuel for use in a heater having an atomizing burner, comprising the steps of:

• directing a first volume of fuel from a fuel tank to an inlet of an inline heater;
• directing a second volume of fuel from the burner to the inline heater via a return line;
• combining the first and second volumes of fuel in the inline heater to form a combined volume of fuel;
• heating the combined volume of fuel in the inline heater using an electrical heating element;
• directing the combined volume of fuel through an outlet in the inline heater to an inlet of a fuel filter;
• filtering the combined volume of fuel using the fuel filter;
• directing the combined volume of fuel to nozzles that open into a combustion chamber of the burner;
• burning a portion of the combined volume of fuel in the combustion chamber;
• directing an unused volume of the combined fuel into the return line, the unused volume of the combined fuel comprising at least 50% of the combined volume of fuel;
• directing the unused volume of the combined fuel from the return line into an inlet of a valve, the valve being switchable to selectively couple the inlet to only a first outlet or a second outlet, respectively;
• and
• wherein the unused volume of the combined fuel is either selectively diverted to the first outlet during a purge of the supply line and return line, or selectively diverted to the second outlet during recirculation of the unused volume of the combined fuel directly to an inlet of the inline heater, independent of operating temperature.