High-efficiency heating apparatus

A method of manufacturing a deep fryer, comprising:

• providing a cooking vessel for holding a cooking medium, the cooking vessel having a chamber having a front wall, a rear wall, and opposing sidewalls;
• and
• coupling a natural draft combustion system to the cooking vessel, the natural draft combustion system being formed by:
• providing at least one supply conduit for receiving and distributing a combustion gas;
• placing at least one burner in fluid communication with the at least one supply conduit;
• providing at least one nozzle in fluid communication with the at least one supply conduit;
• providing a jet in fluid communication with each nozzle, the jet being coupled to the at least one burner;
• disposing a fixed element near the entrance of the combustion chamber for directing secondary air into the combustion chamber;
• and
• connecting at least one combustion chamber to an exterior surface of one of the sidewalls, such that the at least one combustion chamber is in fluid communication with the at least one burner and is in heat transfer communication with the exterior surface of one of the sidewalls;
• such that the combustion gas is distributed from the supply conduit, through the at least one nozzle, into the jet, and into the at least one burner;
• thereby allowing the combustion gas to be partially premixed with air prior to entering the combustion chamber and to be mixed with the secondary air within the combustion chamber.

A method of cooking food, comprising:

• placing a cooking medium into a cooking vessel having a front wall, a rear wall, and opposing sidewalls;
• heating the cooking medium with a natural draft combustion system having at least one supply conduit for receiving and distributing a combustion gas, at least one burner in fluid communication with the at least one supply conduit, at least one nozzle in fluid communication with the at least one supply conduit, a jet in fluid communication with each nozzle, the jet being coupled to the at least one burner, at least one combustion chamber connected along an exterior surface of one of the sidewalls, such that the at least one combustion chamber is in fluid communication with the at least one burner and is in heat transfer communication with the exterior surface of one of the sidewalls, and a fixed element near the entrance of the combustion chamber for directing secondary air into the combustion chamber, such that the combustion gas is distributed from the supply conduit, through the at least one nozzle, into the jet, and into the at least one burner;
• and
• cooking the food in the heated cooking medium.

A deep fryer, comprising:

• a cooking vessel for holding a cooking medium, the cooking vessel having a chamber having a front wall, a rear wall, and opposing sidewalls;
• and
• a natural draft combustion system comprising:
• a supply conduit for receiving and distributing a combustion gas;
• a burner in fluid communication with the supply conduit;
• a nozzle in fluid communication with the supply conduit;
• a jet in fluid communication with each nozzle, the jet being coupled to the at least one burner;
• a combustion chamber in fluid communication with the burner, the combustion chamber being in heat transfer communication with an exterior surface of one of the sidewalls;
• and
• a fixed element disposed near the entrance of the combustion chamber for directing secondary air into the combustion chamber;
• whereby the combustion gas is distributed from the supply conduit, through the at least one nozzle, into the jet, and into the at least one burner;
• wherein the combustion gas is partially premixed with air prior to entering the combustion chamber and is mixed with the secondary air within the combustion chamber;
• and
• wherein the burner is configured such that combustion of the combustion gas is initiated prior to entry into the combustion chamber.