Patent application number | Description | Published |
20090211540 | FUEL-FIRED, POWER VENTED HIGH EFFICIENCY WATER HEATER APPARATUS - A fuel-fired water heater has a draft inducer fan assembly with a housing having an inlet for receiving hot combustion gases discharged from the water heater, and an outlet for discharging the combustion gases. A normally closed damper member within the housing is openable by fluid pressure force created by operation of a draft inducer fan portion of the assembly. With the damper in its open position the fan exhausts the received combustion gases through a housing outlet. When the damper closes it prevents convective outflow through the housing outlet of flue-heated air. In alternate embodiments of the assembly the fan is operative to also draw in dilution air that cools the fan motor and the discharged combustion gases, with the assembly having an internal configuration preventing convective outflow of flue-heated air through the housing dilution air inlet during standby periods of the water heater. | 08-27-2009 |
20100193593 | Water Heater Monitor/Diagnostic Display Apparatus - A water heater is provided with monitor/diagnostic display apparatus that selectively provides a user with visual or other type of indicia of the recovery time for 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. | 08-05-2010 |
20110214621 | HIGH EFFICIENCY GAS-FIRED WATER HEATER - The efficiencies of illustrative embodiments of vertical center flue type fuel-fired base water heaters are improved by installing in the water heaters variously configured tubular condensing type secondary heat exchangers of smaller diameters than the associated center flues. The efficiency increases are achieved with components and manufacturing processes similar to those utilized in the base water heaters and secondary heat exchanger materials similar to those in the tank portions of the base water heaters. | 09-08-2011 |
20140053791 | Downfired High Efficiency Gas-Fired Water Heater - A high efficiency downfired gas water heater is provided which has a tank for storing water to be heated, a combustion chamber extending downwardly through a top end of the tank, and a gas burner operative to create hot combustion products within the combustion chamber. At the bottom end of the tank is a transfer chamber coupled to an external discharge conduit and to a single pass heat exchanger, in the form of multiple flue tubes. extending vertically through the tank and connected to the combustion chamber. In one embodiment of the water heater the burner is a power burner which forces the combustion products sequentially through the combustion chamber, heat exchanger, transfer chamber and discharge conduit. In another embodiment of the water heater a draft inducer fan is used to draw the combustion products through this path from the combustion chamber. | 02-27-2014 |
20140096726 | PILOT BURNER SYSTEM FOR WATER HEATERS - A tube disposed in the combustion chamber of a standing pilot type fuel-fired water heater is used to increase the overall efficiency of the water heater by improving the heat transfer from the pilot flame to the tank during standby periods by funneling the standing pilot flame upwardly through the tube in a manner concentrating the pilot flame heat against an underside portion of the bottom head of the water heater tank. To further increase water heater efficiency, the pilot burner is of a dual input type. Various pilot burner operational algorithm modes are disclosed for causing the pilot burner to operate at a high firing rate during main burner operation, and at a low firing rate during standby periods. | 04-10-2014 |
20140120484 | FLUE DAMPER CONTROL ALGORITHM FOR STANDING PILOT TYPE FUEL-FIRED WATER HEATER - In a fuel-fired water heater with a standing pilot burner and a motorized flue damper, a specially designed controller is utilized to prevent overheating of water stored in the tank portion of the water heater caused by the hot combustion gases continuously generated by the pilot burner during standby periods of the water heater in which its main fuel burner is not being fired. The controller has a selectively variable water temperature control set point temperature and is operable to sense both ambient temperature and the tank water temperature and to open the flue damper and/or keep it open, after the main burner is off, in response to the presence for a predetermined continuous time period of a predetermined relationship of at least the selected temperature control set point temperature and the sensed ambient temperature | 05-01-2014 |
20140241708 | ELECTRONIC CONTROL SYSTEM FOR ELECTRIC WATER HEATER - In an electric water heater having adjustable set point and differential temperatures, upper and lower heating elements, and associated temperature sensors respectively operative to sense upper and lower tank water temperatures, a specially designed control system is provided for controlling the heating elements. The control system is operative to automatically set a selected setpoint temperature to a second setpoint temperature less than or equal to a predetermined magnitude, and to reduced the second setpoint temperature and/or the differential temperature, as a predetermined function of the magnitudes of detected time intervals between successive heat demands of the water heater, to reduce the energy cost associated with the water heater. | 08-28-2014 |
20140376899 | Cathodic Corrosion and Dry Fire Protection Apparatus and Methods for Electric Water Heaters - The metal tank portion of an electric water heater is protected against corrosion utilizing a corrosion protection system that detects a voltage potential between the sheath portion of a tank water-immersed electric heating element and the tank. In one embodiment of the corrosion protection system the sensed sheath/tank potential is utilized to enable a user of the water heater to accurately gauge the necessity of replacing a sacrificial anode extending into the tank. In another corrosion protection system, the sensed sheath/tank potential is utilized to provide impressed current cathodic protection of the tank and also to prevent dry firing of the electric water heater. | 12-25-2014 |
Patent application number | Description | Published |
20080197817 | CONTROL ARRANGEMENT FOR A PFC POWER CONVERTER - In a PFC (Power Factor Correction) converter control unit, a PWM (pulse width modulated) signal is produced by comparing a PFC converter output voltage error signal, produced by a transconductance amplifier, with a ramp signal, which may be from a control unit of a resonant mode converter in cascade with the PFC converter. Level shifting is used to match the amplitude ranges of the compared signals. A current, representing an input current of the PFC converter and produced by a current mirror, is switched by the PWM signal to a parallel resistance and capacitance to produce a smoothed voltage constituting a control signal for the PFC converter. | 08-21-2008 |
20090091957 | CASCADED PFC AND RESONANT MODE POWER CONVERTERS - A control unit controls cascaded PFC and LLC converters, the LLC converter having an input coupled to an output, of the PFC converter and providing an output voltage that decreases with increasing switching frequency. The control unit produces a sawtooth waveform with a linear ramp for controlling the LLC converter switching frequency, and hence its output voltage, in dependence upon a feedback signal. It also produces for the PFC converter a PWM signal with a frequency that is the same as or an integer fraction of the LLC converter switching frequency, by comparing two thresholds with the linear ramp in respective different cycles of the sawtooth waveform to turn on and off a switch of the PFC converter during these different cycles. Logic circuits prevent PFC converter switch transitions from occurring simultaneously with switching transitions of the LLC converter. | 04-09-2009 |
20090128114 | POWER SUPPLY OUTPUT VOLTAGE TRIMMING - A power supply trim control signal is produced by integrating differences between monitored and target values of the output voltage of a power supply. Register storage requirements are reduced by producing the target value from a nominal voltage value and one of a plurality of margin offsets selected in accordance with control data. The control data also selects between open and closed loop trim control. Stability is enhanced by changing the target value slowly in response to any change in the control data. | 05-21-2009 |
20110095734 | CASCADED PFC AND RESONANT MODE POWER CONVERTERS - A power supply includes a PFC (power factor correction) converter that has an input and an output. The PFC converter input is coupled to an input of the power supply. The power supply also includes a resonant mode converter that has an input and an output. The resonant mode converter input is coupled to the PFC converter output and the resonant mode output is coupled to an output of the power supply. A control unit is also included in the power supply and is coupled to receive a feedback signal that is representative of the output of the power supply. The control unit is coupled to provide control signals coupled to control switches of the resonant mode converter at a controlled switching frequency to control the output of the power supply. The control unit is further coupled to provide a PFC control signal coupled to control a switch of the PFC converter at a switching frequency that is harmonically related to the controlled switching frequency. | 04-28-2011 |
20110134670 | CONTROL ARRANGEMENT FOR A PFC POWER CONVERTER - In a PFC (power factor correction) control unit for controlling a PFC converter, a transconductance amplifier is coupled to receive a feedback signal representative of an output voltage of the PFC converter. The transconductance amplifier is coupled to generate an output error signal in response to the feedback signal. A PWM (pulse width modulated) converter is coupled to receive the output error signal, the PWM converter is coupled to generate a PWM signal in response to the output error signal. A chopper is coupled to receive the PWM signal. The chopper is coupled to switch a current representative of an input current of the PFC converter in response to the PWM signal. A filter is coupled to receive the switched current representative of the input current of the PFC converter. The filter is coupled to generate a PFC converter control signal in response to the filtered switched current representative of the input current of the PFC converter. | 06-09-2011 |