Instantaneous fuel-fired water heater with low temperature plastic vent structure
AssigneeRheem Manufacturing Company
InventorsJozef Boros, Subbu Thenappan
Life of this patent
Estimating the term…
Abstract
An instantaneous type fuel-fired water heater has a variable speed blower that discharges combustion air into a fuel burner utilized to heat water flowing through a heat exchanger portion of the water heater. A portion of the air discharged from the blower bypasses the burner and associated heat exchanger, flows around the heat exchanger, and then mixes with flue gases being discharged from the heat exchanger portion into the flue portion of the water heater. In this manner, such flue gases are cooled by the bypassing blower discharge air to an extent permitting the flue portion to be formed from a low cost plastic material instead of a high temperature metal material such as stainless steel.
Claims30
Fuel-fired fluid heating apparatus comprising:
- an outer housing having a combustion gas outlet opening;
- a heat exchanger structure disposed in said outer housing and having a first flow path extending therethrough and adapted to receive and discharge a flow of fluid to be heated, and a second flow path extending therethrough, said second flow path being in thermal communication with said first flow path and adapted to receive a flow of hot combustion gas and discharge it through said combustion gas outlet opening;
- wall structure defining a third flow path external to said heat exchanger structure, said third flow path being interposed between and at least partially bounded by an interior surface portion of said outer housing and an exterior surface portion of said heat exchanger structure;
- a fuel burner operative to receive fuel and pressurized combustion air from sources thereof, combust the received fuel and combustion air, and create said flow of hot combustion gas;
- and
- blower apparatus operative to (1) discharge a first flow of air into said fuel burner as pressurized combustion air, and (2) discharge a second flow of air into said third flow path as cooling air which flows along an interior surface portion of said outer housing and mixes with and cools combustion gas being discharged from said second flow path.
A fuel-fired instantaneous type water heater comprising:
- an outer housing having a combustion gas outlet opening;
- a combustion chamber disposed within said outer housing;
- a heat exchange structure, disposed within said combustion chamber for receiving a throughflow of water to be heated;
- a fuel burner operable to create hot combustion gas within said combustion chamber;
- a cooling air flow path external to said combustion chamber;
- and
- blower apparatus operative to (1) discharge a first flow of air into said fuel burner as pressurized combustion air which forces said combustion gas outwardly from said combustion chamber and outwardly through said combustion gas outlet opening, and (2) discharge a second flow of air into said cooling air flow path as cooling air which mixes with and cools combustion gas being discharged from said combustion chamber.
Dependencies are inferred from the claim text.