Abstract: A water heater is provided with monitor/diagnostic display apparatus that selectively provides a user with visual or other type of indicia of the remaining hot water availability of, the recovery time for, and the overall efficiency of the water heater. The apparatus includes a monitoring unit that may be mounted on the water heater, and a display unit that may be mounted either on the water heater or remotely therefrom.

Abstract: In a flammable vapor sensor-based shut-off system of a fuel-fired water heater the sensor resistance output signal degradation caused by aging of the sensor is automatically compensated for using an operational timer having an output signal indicative of the total life of the sensor subsequent to its installation on the water heater. In one embodiment of the system, a resistance adjustment signal having a magnitude related in a predetermined manner to the timer output signal is created and added to the sensor resistance output signal. In another embodiment, the timer output signal is used to appropriately adjust the minimum-maximum received sensor signal magnitude range, based on the installed age of the sensor, which will preclude combustion in the appliance. Additionally, in each embodiment thereof the system is provided with an improved initial minimum-maximum sensor signal magnitude range. Other types of shut-off gas sensors may be alternatively utilized.

Abstract: A transistor used as a normally open switch is connected in the millivolt electrical circuit of a fuel-fired natural draft water heater in series with a thermopile device impinged upon by a standing pilot flame, and the solenoid coil portion of the pilot fuel valve. A variable resistance type flammable vapor sensor is connected in a control circuit which is powered by a DC battery and is coupled only to the transistor portion of the millivolt circuit. In the absence of flammable vapor detection by the sensor the control circuit outputs an electrical signal to the transistor that holds it in a closed position to thereby maintain the standing pilot flame. In response to sensor detection of flammable vapor, the control circuit output signal terminates to cause the transistor to return to its normally open switch position, thereby shutting off the pilot flame.

Abstract: In a flammable vapor sensor-based shut-off system of a fuel-fired water heater the sensor resistance output signal degradation caused by aging of the sensor is automatically compensated for using an operational timer having an output signal indicative of the total life of the sensor subsequent to its installation on the water heater. In one embodiment of the system, a resistance adjustment signal having a magnitude related in a predetermined manner to the timer output signal is created and added to the sensor resistance output signal in another embodiment, the timer output signal is used to appropriately adjust the minimum-maximum received sensor signal magnitude range, based on the installed age of the sensor, which will preclude combustion in the appliance. Additionally, in each embodiment thereof the system is provided with an improved initial minimum-maximum sensor signal magnitude range. Other types of shut-off gas sensors may be alternatively utilized.

Abstract: A ball valve includes a body having a passageway there through with a ball member disposed in the passageway and mounted for selective rotation between valve open and valve closed positions to control fluid flow. A pair of flange grooves are provided in the body on opposite sides of the ball, each flange groove extending radially from the passageway. A pair of seat rings are disposed in the passageway on opposite sides of the ball. Each seat ring has a first sealing surface in contact with an outer surface of the ball and a radially extending annular flange or tab received in an associated one of the flange grooves. The seat design further includes a pair of annular flange seals each disposed in a respective one of the flange grooves. The seat configuration achieves a cantilever effect to improve the temperature and pressure cycling performance of the valve.

Abstract: A gas-fired water heater is provided with a combustion shutoff system which precludes further combustion within the water heater's combustion chamber in response to a combustion temperature therein reaching a predetermined level correlated to and indicative of a predetermined, undesirably high concentration of carbon monoxide present in the combustion chamber. In various illustrated embodiments thereof, the combustion shutoff system is operative to terminate further combustion air inflow to the combustion chamber, or terminate further fuel flow to the burner portion of the water heater.

Abstract: A gas-fired water heater is provided with a combustion shutoff system which precludes further combustion within the water heater's combustion chamber in response to a combustion temperature therein reaching a predetermined level correlated to and indicative of a predetermined, undesirably high concentration of carbon monoxide present in the combustion chamber. In various illustrated embodiments thereof, the combustion shutoff system is operative to terminate further combustion air inflow to the combustion chamber, or terminate further fuel flow to the burner portion of the water heater.

Abstract: A gas-fired water heater is provided with a combustion shutoff system which precludes further combustion within the water heater's combustion chamber in response to a combustion temperature therein reaching a predetermined level correlated to and indicative of a predetermined, undesirably high concentration of carbon monoxide present in the combustion chamber. In various illustrated embodiments thereof, the combustion shutoff system is operative to terminate further combustion air inflow to the combustion chamber, or terminate further fuel flow to the burner portion of the water heater.

Abstract: A gas-fired water heater is provided with a combustion shutoff system which precludes further combustion within the water heater's combustion chamber in response to a combustion temperature therein reaching a predetermined level correlated to and indicative of a predetermined, undesirably high concentration of carbon monoxide present in the combustion chamber. In various illustrated embodiments thereof, the combustion shutoff system is operative to terminate further combustion air inflow to the combustion chamber, or terminate further fuel flow to the burner portion of the water heater.

Abstract: A gas-fired water heater is provided with a combustion shutoff system which precludes further combustion within the water heater's combustion chamber in response to a combustion temperature therein reaching a predetermined level correlated to and indicative of a predetermined, undesirably high concentration of carbon monoxide present in the combustion chamber. In various illustrated embodiments thereof, the combustion shutoff system is operative to terminate further combustion air inflow to the combustion chamber, or terminate further fuel flow to the burner portion of the water heater.

Abstract: A fuel-fired, power vented water heater has a combustion chamber with an outer wall portion defined by an arrestor plate in which flame quenching air inlet openings are formed. All combustion air entering the combustion chamber must first pass through an air inlet plenum extending outwardly from the arrestor plate and then pass inwardly through the flame quenching openings into the combustion chamber. The air inlet plenum is provided with a normally closed inlet damper which automatically closes during non-firing periods of the water heater to prevent passage of combustion air (and extraneous flammable vapors, if present, adjacent the water heater) into the combustion chamber, and opens during firing periods of the water heater to permit operative combustion air delivery to the combustion chamber.

Abstract: A gas-fired water heater has a combustion chamber with a bottom wall defined by a perforated flame arrestor plate forming a portion of a flow path through which combustion air may be supplied to a burner structure within the combustion chamber. During firing of the water heater a combustion air shutoff system having a heat-frangible temperature sensing structure disposed within the combustion chamber senses an undesirable temperature increase in the combustion chamber, caused by for example a partial blockage of the flow path, and responsively terminates further air flow into the combustion chamber, thereby shutting down the burner, prior to the creation in the combustion chamber of a predetermined elevated concentration of carbon monoxide.

Abstract: A ball valve includes a body having a passageway there through with a ball member disposed in the passageway and mounted for selective rotation between valve open and valve closed positions to control fluid flow. A pair of flange grooves are provided in the body on opposite sides of the ball, each flange groove extending radially from the passageway. A pair of seat rings are disposed in the passageway on opposite sides of the ball. Each seat ring has a first sealing surface in contact with an outer surface of the ball and a radially extending annular flange or tab received in an associated one of the flange grooves. The seat design further includes a pair of annular flange seals each disposed in a respective one of the flange grooves. The seat configuration achieves a cantilever effect to improve the temperature and pressure cycling performance of the valve.

Abstract: A gas-fired water heater has a combustion chamber with a bottom wall defined by a perforated flame arrestor plate forming a portion of a flow path through which combustion air may be supplied to a burner structure within the combustion chamber. During firing of the water heater a combustion air shutoff system having a heat-frangible temperature sensing structure disposed within the combustion chamber senses an undesirable temperature increase in the combustion chamber, caused by for example a partial blockage of the flow path, and responsively terminates further air flow into the combustion chamber, thereby shutting down the burner, prior to the creation in the combustion chamber of a predetermined elevated concentration of carbon monoxide.

Abstract: A fuel-fired power vented heating appliance, representatively a water heater, has, in its draft structure, a single thermal or other type of cutoff switch which serves the dual function of preventing (1) the creation of an unacceptably high level of carbon monoxide in the combustion chamber of the appliance, and (2) thermal damage to a PVC vent pipe portion of the draft structure. When triggered, the cutoff switch operates to terminate further firing of the appliance. In one illustrative embodiment of the appliance, this is achieved by preventing further combustion air flow to the appliance. In another illustrative embodiment of the appliance, it is achieved by terminating further fuel flow thereto.

Abstract: A gas-fired water heater has a combustion chamber with a bottom wall defined by a perforated flame arrestor plate forming a portion of a flow path through which combustion air may be supplied to a burner structure within the combustion chamber. During firing of the water heater a combustion air shutoff system having a heat-frangible temperature sensing structure disposed within the combustion chamber senses an undesirable temperature increase in the combustion chamber, caused by for example a partial blockage of the flow path, and responsively terminates further air flow into the combustion chamber, thereby shutting down the burner, prior to the creation in the combustion chamber of a predetermined elevated concentration of carbon monoxide.

Abstract: A gas-fired water heater has a combustion chamber with a bottom wall defined by a perforated flame arrestor plate forming a portion of a flow path through which combustion air may be supplied to a burner structure within the combustion chamber. During firing of the water heater a combustion air shutoff system having a heat-frangible temperature sensing structure disposed within the combustion chamber senses an undesirable temperature increase in the combustion chamber, caused by for example a partial blockage of the flow path, and responsively terminates further air flow into the combustion chamber, thereby shutting down the burner, prior to the creation in the combustion chamber of a predetermined elevated concentration of carbon monoxide.

Abstract: A gas-fired water heater has a combustion chamber with a bottom wall defined by a perforated flame arrestor plate forming a portion of a flow path through which combustion air may be supplied to a burner structure within the combustion chamber. During firing of the water heater a combustion air shutoff system having a heat-frangible temperature sensing structure disposed within the combustion chamber senses an undesirable temperature increase in the combustion chamber, caused by for example a partial blockage of the flow path, and responsively terminates further air flow into the combustion chamber, thereby shutting down the burner, prior to the creation in the combustion chamber of a predetermined elevated concentration of carbon monoxide.

Abstract: A ball valve (10) includes a body (A) having a passageway (12) extending therethrough with a ball member (B) disposed in the passageway and mounted for selective rotation between valve open and valve closed positions to control fluid flow through the valve. A pair of flange grooves are provided in the body on opposite sides of the ball. each flange groove extending radially from the passageway. A pair of seat rings (16) are disposed in the passageway on opposite sides of the ball. Each seat ring has a first sealing surface (24) in contact with an outer surface of the ball and a radially extending annular flange or tab (30) received in an associated one of the flange grooves (34). The seat design further includes a pair of annular flange seals (18, 20) each disposed in a respective one of the flange grooves.

Abstract: A gas-fired water heater is provided with a combustion shutoff system which precludes further combustion within the water heater's combustion chamber in response to a combustion temperature therein reaching a predetermined level correlated to and indicative of a predetermined, undesirably high concentration of carbon monoxide present in the combustion chamber. In various illustrated embodiments thereof, the combustion shutoff system is operative to terminate further combustion air inflow to the combustion chamber, or terminate further fuel flow to the burner portion of the water heater.