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AssigneeCarrier Corporation
InventorsDaniel J. Dempsey, Ninev Karl Zia, Timothy J. Waterman
Estimating the term…
A furnace is provided with a flame rollout protection system which operates through an existing excess-air control pneumatic circuitry to shut down the furnace in the event of a flame rollout condition. A fusible tube is attached at its one end to the pneumatic system and extends into an area which will be exposed to hot gases in the event of a flame rollout condition. A melting of the tube by the hot gases causes the pressure therein to drop to ambient pressure such that of the pneumatic circuitry responsively causes the furnace to shut down. The tube is also extended to pass through an area which will be exposed to hot gases in the event of a blocked vent in the furnace, thereby causing a similar shut down of the furnace.
In a furnace of the type having a combustion circuit including burners, heat exchangers and a pneumatic circuit for sensing the pressure drop within the combustion circuit, a system for responding to excessive temperatures that may result from undesirable operating conditions, comprising:
A flame rollout protection system for a furnace of the type having at least one burner that is susceptible to a flame rollout condition, comprising:
A furnace of the type having burners, heat exchangers and a pneumatic circuit for sensing the pressure drop across the heat exchangers for purposes of determining if there is sufficient air to data support combustion, comprising:
A furnace is set forth in claimed 11 wherein said pressure fusible element also extends across an area that would be exposed to hot gases in the event of a blocked vent in said furnace such that said pressure tube will be caused by said hot gases to partially melt and cause the pressure in said pressure tube to go towards ambient pressure thereby causing said pneumatic circuit to shut down the furnace operation.
Dependencies are inferred from the claim text.