Vented backplate impeller water heater blower and method of mixing dilution air
AssigneeFasco Industries, Inc.
InventorDale D. Stewart
Life of this patent
Estimating the term…
Abstract
A dilution air blower that has a reverse-mounted impeller contained within a combined blower housing and impeller housing. The impeller includes a vented backplate that is positioned to face a base opening of the blower housing that receives the exhaust gas from an appliance, such as a water heater. Rotation of the impeller causes the impeller to draw in a supply of dilution air which passes over the blower motor. The dilution air mixes with the exhaust gases within the mixing chamber of the impeller. The mixture of gases is discharged radially from the impeller through an exhaust outlet. The invention eliminates the need for fans dedicated to cool the blower motor while providing the required mixture of the exhaust gases and the dilution air.
Claims15
A dilution air blower, comprising:
- a blower housing having a gas inlet for receiving a first gas, the blower housing defining a base opening, wherein the base opening is positioned to receive a second gas;
- a blower motor mounted within the blower housing, the blower motor having a rotatable central motor shaft;
- and
- an impeller mounted to the motor shaft for rotation with the motor shaft, the impeller being positioned within the blower housing, the impeller including a mixing chamber defined by a backplate and an inlet opening, the backplate including a plurality of vents that allow gas to pass through the backplate and into the mixing chamber;
- wherein upon rotation of the impeller, the first gas and the second gas are drawn into the mixing chamber and mixed therein.
A dilution air blower for mixing an exhaust gas from a water heater with dilution air, the blower comprising:
- a blower housing having a dilution air inlet open to atmosphere to receive the dilution air, the blower housing including a base opening that is positioned to receive the exhaust gas, the blower housing further including an exhaust outlet;
- a blower motor positioned within the blower housing, the blower motor having a rotatable central motor shaft;
- and
- an impeller mounted to the motor shaft for rotation with the motor shaft, the impeller being rotatably positioned within the blower housing, the impeller including a mixing chamber defined by a backplate and an inlet opening, the backplate having a plurality of vents that allow the exhaust gas to pass through the backplate, the impeller being mounted to the motor shaft such that the inlet opening faces the dilution air inlet and the backplate faces the base opening of the blower housing;
- wherein rotation of the impeller causes the dilution air to enter the mixing chamber through the inlet opening of the impeller and causes exhaust gas to enter the mixing chamber through the vented backplate of the impeller.
A method of diluting exhaust gases from a water heater, the method comprising the steps of:
- providing a dilution air blower at the exhaust discharge of the water heater, the dilution air blower comprising:
- a blower housing having a gas inlet open to atmosphere for receiving dilution air, the blower housing including a base opening that is positioned to receive the exhaust gas, the blower housing further including an exhaust outlet;
- a blower motor positioned within the blower housing, the blower motor having a rotatable central motor shaft;
- an impeller mounted to the motor shaft and rotatably positioned within the blower housing, the impeller including a mixing chamber defined by a backplate and an inlet opening, the backplate having a plurality of vents positioned to face the base opening of the blower housing;
- rotating the impeller to develop negative air pressure in the mixing chamber to draw dilution air through the inlet opening and to draw exhaust gases through the vented backplate;
- mixing the exhaust gas with the dilution air in the mixing chamber of the impeller;
- and
- expelling the gas mixture from the dilution air blower via the exhaust outlet.
Dependencies are inferred from the claim text.