Abstract: A device that heats/cools air includes a heat exchanger that contains hydronic fluid; a blower that moves air over and/or through the heat exchanger; a pump that circulates the hydronic fluid; a first vessel that contains hydronic fluid under pressure, air, a sealed first opening, a second opening that allows the hydronic fluid to exit the first vessel, a third opening that allows the hydronic fluid to enter the vessel, and a fourth opening; a second vessel that contains hydronic fluid at atmospheric pressure, a sealed first opening, and a second opening in communication with the first vessel, wherein the second vessel is in communication with the fourth opening; a valve that allows hydronic fluid to flow from the second vessel to the first vessel when pressure inside the first vessel decreases below zero psig, and prevents hydronic fluid from flowing from the first vessel to the second vessel.

Abstract: An electronic expansion valve (EEV) is operated by a motor controlling a variable restriction valve in which a liquid refrigerant enters at a high pressure and exits at a reduced pressure. The motor controls the depth of a tapered needle which, as extended, penetrates multiple fixed orifices, aligned in series. Additional fixed orifices, downstream of the fully extended needle, provide further restriction and management of refrigerant flashing. Depending on the desired operating range, the following elements may be controlled: needle length, diameter, and taper; diameter, thickness, and relative elevation of each orifice; response and maximum torque provided by the motor; and geometry of the valve enclosed volume.

Abstract: A method operates an absorption heat pump system, specifically the flow of hydronic cooling fluid through the condenser during system start-ups, or when the cooling fluid temperature is low. To minimize the time for an absorption heat pump to reach full cooling or heating capacity, it is desirable for the high side pressure to increase as fast as possible, and the low side pressure to decrease as fast as possible. Since the high side pressure is a function of the temperature of the refrigerant exiting the condenser, if the condenser cooling fluid temperature is low, the corresponding high side pressure will be low, which may not permit adequate working fluid flow rates from the high pressure side of the system to the low pressure side.

Abstract: A heat exchanger has an outer tube and an inner tube extending through a lumen of the outer tube. The outer tube has a spiral corrugation and an inner surface of the corrugation contacts or is in proximity to an exterior surface of the inner tube to define a spiral annular channel in an annular space between the inner tube and outer tube.

Abstract: An electronic expansion valve (EEV) is operated by a motor controlling a variable restriction valve in which a liquid refrigerant enters at a high pressure and exits at a reduced pressure. The motor controls the depth of a tapered needle which, as extended, penetrates multiple fixed orifices, aligned in series. Additional fixed orifices, downstream of the fully extended needle, provide further restriction and management of refrigerant flashing. Depending on the desired operating range, the following elements may be controlled: needle length, diameter, and taper; diameter, thickness, and relative elevation of each orifice; response and maximum torque provided by the motor; and geometry of the valve enclosed volume.

Abstract: A multi-function heating and cooling device, comprising components for an ambient air-coupled sorption heat pump cycle and vapor compression cooling cycle integrated together inside a single enclosure is proposed. The sorption heat pump portion is configured to provide very high heating efficiency, while the vapor compression portion is configured to provide high cooling efficiency. The evaporator coil for the sorption cycle and the condenser coil for the vapor compression cycle are configured to share a common ambient-air fan, saving space and cost. By combining the two heating-cooling systems into a single enclosure with shared components, the total installed cost and outdoor space required is reduced compared to installing separate heating and cooling systems.

Abstract: A method operates an absorption heat pump system, specifically the flow of hydronic cooling fluid through the condenser during system start-ups, or when the cooling fluid temperature is low. To minimize the time for an absorption heat pump to reach full cooling or heating capacity, it is desirable for the high side pressure to increase as fast as possible, and the low side pressure to decrease as fast as possible. Since the high side pressure is a function of the temperature of the refrigerant exiting the condenser, if the condensor cooling fluid temperature is low, the corresponding high side pressure will be low, which may not permit adequate working fluid flow rates from the high pressure side of the system to the low pressure side.

Abstract: A heat activated (preferably natural gas, propane, solar or waste heat fired) absorption heat pump water heater and heat exchange system. The heat driven absorption heat pump system extracts low grade heat from the ambient air and produces high grade heat suitable for heating water for domestic, climate control or process purposes in a storage tank. Flue gases exiting the absorption heat pump system are further cooled by the heated water to enable high (condensing) combustion efficiencies. The heat activated heat pump water heating system achieves COP of 1.5 or greater.

Abstract: A gas-fired heating device having a burner, a pilot to provide a pilot flame, a thermopile thermally coupled to the pilot flame and configured to generate a power in response to the pilot flame, an electrically controlled gas valve to control the flow of gas to at least one of the pilot and the burner, and a controller electrically coupled to the thermopile and the gas valve. The controller receives and is powered by the power from the thermopile. The controller initiates closing of the gas valve after a monitored component of the power, such as a voltage, traverses a threshold.

Abstract: A heat activated (preferably natural gas, propane, solar or waste heat fired) absorption heat pump water heater and heat exchange system. The heat driven absorption heat pump system extracts low grade heat from the ambient air and produces high grade heat suitable for heating water for domestic, climate control or process purposes in a storage tank. Flue gases exiting the absorption heat pump system are further cooled by the heated water to enable high (condensing) combustion efficiencies. The heat activated heat pump water heating system achieves efficiencies of 150% or greater.

Abstract: A low NOx water heater including a water container, a combustion chamber adjacent the water container, a burner associated with the combustion chamber and arranged to combust fuel to heat water in the water container, the burner comprising a plenum chamber having a combustion surface and a fuel/air conduit adapted to receive fuel and air, and a fuel nozzle positioned to supply fuel into the fuel/air conduit at an angle that is between about 1.5° and about 2.5° out of horizontal relative to a horizontal plane extending along a central axis of the fuel/air conduit.

Abstract: A water heater including a water container, a combustion chamber adjacent the water container, a burner associated with the combustion chamber, a blower located to receive combustion products generated by the burner, an intake air conduit connected to the combustion chamber and having a combustion air intake opening, a dilution air conduit connected to the blower and having a dilution air intake opening; and a flammable vapor sensor having at least an operative portion positioned in the blower or the dilution air conduit.

Abstract: A combustion chamber is disposed below the water container of a water heater and formed at least partially by a shell. A burner disposed within the combustion chamber and a fuel supply line is connected to the burner. A valve associated with the fuel supply line. A combustion chamber sensor is disposed within the combustion chamber and adapted to sense a rise in temperature indicative of an abnormality in the combustion chamber. A circuit connected to the sensor and the valve such that the circuit triggers the valve to shut off fuel to the burner in response to a sensed temperature by the sensor.

Abstract: A waste heat source (100) is used to heat a high temperature heat transfer fluid which is used to heat an absorption heat transfer machine (10) having a generator (20), an absorber (30), a condenser (40), and an evaporator (50) operatively connected together. The high temperature heat transfer fluid can also be used to heat a load (190) such as a room space or a process. The waste heat source (100) can also be used to heat an intermediate heat transfer fluid, which can be used to heat a second load (175) such as a space, a process, or an absorption heat transfer machine. Novel flow control devices (70, 60) for controlling the flow of weak solution from generator (20) to absorber (30) or of refrigerant from condenser (40) to evaporator (50), respectively, are also described.

Abstract: A low NOx water heater including a water container; a combustion chamber adjacent the water container having an opening covered with an open flame arrestor; a burner associated with the combustion chamber and arranged to combust fuel to heat water in the water container, the burner including a plenum chamber having a combustion surface and a fuel/air conduit adapted to receive fuel and air and extending between and sealed to the plenum and a wall of the combustion chamber; and a heat resistant acoustic absorber positioned on the wall.

Abstract: A water heater including a water container, a combustion chamber adjacent the water container, a burner associated with the combustion chamber, a flue gas collector located to receive flue gases generated in the combustion chamber, a CO sensor having at least an operative portion proximate the flue gas collector, a flammable vapor sensor having at least an operative portion positioned proximate a location where combustion air enters the combustion chamber, and a controller operatively connected to the CO and flammable vapor sensors and adapted to receive signals generated by the CO and flammable vapor sensors and responsively shut off combustion in the combustion chamber.

Abstract: An assembly for a water heater combustion chamber access door including a bracket having a plurality of leg members, each leg member having a distal portion sized and shaped to connect to the door and a proximal portion connected to a hub member having an opening with a slot; and a fuel supply line connector having a tab adapted to engage the slot and another tab adapted to engage the hub member.

Abstract: A water heater including a water container, a combustion chamber adjacent the water container, a burner associated with the combustion chamber, a blower located to receive combustion products generated by the burner, an intake air conduit connected to the combustion chamber and having a combustion air intake opening, a dilution air conduit connected to the blower and having a dilution air intake opening; and a flammable vapor sensor having at least an operative portion positioned in the blower or the dilution air conduit.

Abstract: A combustion chamber is disposed below the water container of a water heater and formed at least partially by a shell. A burner disposed within the combustion chamber and a fuel supply line is connected to the burner. A valve associated with the fuel supply line. A combustion chamber sensor is disposed within the combustion chamber and adapted to sense a rise in temperature indicative of an abnormality in the combustion chamber. A circuit connected to the sensor and the valve such that the circuit triggers the valve to shut off fuel to the burner in response to a sensed temperature by the sensor.

Abstract: A water heater including a water container; a combustion chamber adjacent the water container; a burner associated with the combustion chamber; a blower assembly located to receive combustion products generated by the burner; an intake conduit sealingly connected to the combustion chamber and having a combustion air intake opening located adjacent an upper portion of the water heater; and a dilution air conduit sealingly connected to the blower assembly and having a dilution air intake opening located adjacent a lower portion of the water heater.