Abstract: The present disclosure is directed to systems and methods for automatically shutting off fluid flow through a fluid inlet line of a water heater upon detection of a leak of the water heater. The system may include an electrically powered shutoff assembly operatively coupled to the fluid inlet line, and a capacitor operatively coupled to the electrically powered shutoff assembly. The electrically powered shutoff assembly may be configured to shut off fluid flow through the fluid inlet line upon detection of a leak of the water heater, and the capacitor may be configured to store power received from an external power source. Accordingly, when the electrically powered shutoff assembly does not have access to electric power, the capacitor may power the electrically powered shutoff assembly to shut off fluid flow through the fluid inlet line.

Abstract: The present disclosure is directed to a mechanical and powerless leak detection and shutoff system that may be used in any commercially available water heater, e.g., both gas and electric. The system includes a spring-loaded shutoff assembly having a valve member operatively coupled to a fluid inlet line of the water heater. A handle of the shutoff assembly is maintained in an open configuration via a latching mechanism until a force is applied to cause the latching mechanism to release the handle and actuate the valve member to shutoff fluid flow through the fluid inlet line. The shutoff assembly is operatively coupled to a leak detection assembly via a cable. The leak detection assembly uses a fluid-soluble material that dissolves when exposed to fluid to thereby pull the cable to apply the force to disengage the latching mechanism.

Abstract: A water heating system is provided. The water heating system includes a tank having a wall, a water inlet defined through the wall and configured to allow ingress of water into the tank, and a water outlet defined through the wall and configured to allow egress of water from the tank. The water heating system also includes a first heating element disposed in a first portion of the tank. The first heating element has a substantially elongate shape and is inclined at a first predefined angle with respect to a base of the tank.

Abstract: A leakage mitigation system to trigger a preventive action against detected leakage from a liquid enclosure, includes a leakage detection device disposed along base of the liquid enclosure. The system includes an absorbent that actuates the leakage detection device from a first state to a second state based on a volume of liquid leaked from the liquid enclosure. The device includes a valve coupled to an inlet pipe of the liquid enclosure and configured to allow flow of liquid through the inlet pipe in an open condition thereof and restrict flow of liquid through the inlet pipe in a closed condition thereof. The system further includes a shut-off actuator coupled to the valve and configured to actuate the valve from the open condition to the closed condition in response to the device being actuated from the first state to the second state.

Abstract: Disclosed herein are heat pump systems for water heaters. The heat pump systems can comprise a housing defining an interior chamber, an air inlet, and an air outlet. The air inlet and the air outlet can form an air flow path through the interior chamber, and an evaporator unit can be positioned within the interior chamber such that the air flow path contacts the evaporator unit. The housing can also have a flue pipe having a cross-section to encourage aerodynamic flow and/or side baffles to encourage air flow into the evaporator unit. The housing can also have a second air inlet to increase air flow and a curved elbow around the first air inlet to direct the air flow path. The air flow path can flow from a top side of the housing to a side of the housing, and the air flow path can be reversible.

Abstract: A leakage mitigation system includes a leakage detection device having a canister configured to: (i) contain a first reactant and a second reactant and, (ii) based on a volume of liquid leaked from a tank, allow the first reactant and the second reactant to react with each other to produce a gas. A shut-off valve coupled to an inlet pipe of the tank is configured to actuate between an open condition and a closed condition. Further, a conduit extending between the leakage detection device and the shut-off valve allows flow of the gas from the leak detection device to the shut off valve. In order to mitigate the leakage of water, the shut-off valve is actuated between the open condition and the closed condition based on the pressure exerted thereon by the flow of the gas.

Abstract: A leakage mitigation system includes a leakage detection device having a canister configured to: (i) contain a first reactant and a second reactant and, (ii) based on a volume of liquid leaked from a tank, allow the first reactant and the second reactant to react with each other to produce a gas. A shut-off valve coupled to an inlet pipe of the tank is configured to actuate between an open condition and a closed condition. Further, a conduit extending between the leakage detection device and the shut-off valve allows flow of the gas from the leak detection device to the shut off valve. In order to mitigate the leakage of water, the shut-off valve is actuated between the open condition and the closed condition based on the pressure exerted thereon by the flow of the gas.

Abstract: A water heating system is provided. The water heating system includes a tank having a wall, a water inlet defined through the wall and configured to allow ingress of water into the tank, and a water outlet defined through the wall and configured to allow egress of water from the tank. The water heating system also includes a heating element disposed within the tank, having a substantially elongate shape, and being moveable between a first inclination angle with respect to a base of the tank and a second inclination angle with respect to the base of the tank.

Abstract: A leakage mitigation system to trigger a preventive action against detected leakage from a liquid enclosure, includes a leakage detection device disposed along base of the liquid enclosure. The system includes an absorbent that actuates the leakage detection device from a first state to a second state based on a volume of liquid leaked from the liquid enclosure. The device includes a valve coupled to an inlet pipe of the liquid enclosure and configured to allow flow of liquid through the inlet pipe in an open condition thereof and restrict flow of liquid through the inlet pipe in a closed condition thereof. The system further includes a shut-off actuator coupled to the valve and configured to actuate the valve from the open condition to the closed condition in response to the device being actuated from the first state to the second state.

Abstract: Disclosed herein are heat pump systems for water heaters. The heat pump systems can comprise a housing defining an interior chamber, an air inlet, and an air outlet. The air inlet and the air outlet can form an air flow path through the interior chamber, and an evaporator unit can be positioned within the interior chamber such that the air flow path contacts the evaporator unit. The housing can also have a flue pipe having a cross-section to encourage aerodynamic flow and/or side baffles to encourage air flow into the evaporator unit. The housing can also have a second air inlet to increase air flow and a curved elbow around the first air inlet to direct the air flow path. The air flow path can flow from a top side of the housing to a side of the housing, and the air flow path can be reversible.

Abstract: A water heating system having a tank and one or more heat sources for heating water is provided. The water heating system includes a water outlet for allowing egress of water from the tank and a dip tube for allowing ingress of water into the tank. The dip tube includes a first end for coupling with a water source and a second end disposed proximate a base of the tank for discharging water into the tank through an array of holes. Each of the holes is defined in a side wall of the dip tube and laterally discharges water with respect to a longitudinal axis of the second end of the dip tube.

Abstract: A water heating system is provided. The water heating system includes a tank having a wall, a water inlet defined through the wall and configured to allow ingress of water into the tank, and a water outlet defined through the wall and configured to allow egress of water from the tank. The water heating system also includes a first heating element disposed in a first portion of the tank. The first heating element has a substantially elongate shape and is inclined at a first predefined angle with respect to a base of the tank.

Abstract: A heat exchanger assembly, in particular an exhaust gas cooler, having a gas inlet pipe attached to an inlet diffuser to improve flow distribution of the gas in a case with a heat exchanger core within. The gas inlet pipe configured to disrupt the momentum of flow of the gas due to at least one bend upstream of the inlet diffuser. The gas inlet pipe including at least two intermediate bends which define multiple section of the gas inlet pipe, at least two of the sections redirecting flow of the gas before an outlet of the gas inlet pipe to more evenly distribute the gas at the outlet of the gas inlet pipe upstream of the inlet diffuser.

Abstract: A heat exchanger assembly, in particular an exhaust gas cooler, having a gas inlet pipe attached to an inlet diffuser to improve flow distribution of the gas in a case with a heat exchanger core within. The gas inlet pipe configured to disrupt the momentum of flow of the gas due to at least one bend upstream of the inlet diffuser. The gas inlet pipe including at least two intermediate bends which define multiple section of the gas inlet pipe, at least two of the sections redirecting flow of the gas before an outlet of the gas inlet pipe to more evenly distribute the gas at the outlet of the gas inlet pipe upstream of the inlet diffuser.

Abstract: A method for testing a cooling component in a building HVAC system uses a state-based testing procedure. The method includes providing a control signal to the cooling component. The control signal instructs the cooling component to activate. The method includes monitoring feedback from a temperature sensor configured to measure temperature affected by the cooling component and evaluating a state transition condition by comparing the feedback from the temperature sensor to a threshold value. The state transition condition is satisfied if the feedback is less than the threshold value and not satisfied if the feedback is not less than the threshold value. The method includes transitioning into a pass state in response to the feedback from the temperature sensor satisfying the state transition condition and transitioning into a fail state in response to the feedback from the temperature sensor not satisfying the state transition condition.

Abstract: A fault detection and diagnostics (FDD) system is provided for a refrigeration circuit having an evaporator and a compressor configured to circulate a refrigerant through the evaporator. The FDD system includes a communications interface configured to receive a measurement of a thermodynamic property affected by the refrigeration circuit and a processing circuit having a processor and memory. The processing circuit is configured to use the measured thermodynamic property to determine an expected suction entropy of the refrigerant at a suction of the compressor, use the expected suction entropy to determine an expected thermodynamic discharge property of the refrigerant at a discharge of the compressor, determine an actual thermodynamic discharge property of the refrigerant at the discharge of the compressor, and detect a fault in the refrigeration circuit by comparing the expected thermodynamic discharge property with the actual thermodynamic discharge property.

Abstract: A method for testing a cooling component in a building HVAC system uses a state-based testing procedure. The method includes providing a control signal to the cooling component. The control signal instructs the cooling component to activate. The method includes monitoring feedback from a temperature sensor configured to measure temperature affected by the cooling component and evaluating a state transition condition by comparing the feedback from the temperature sensor to a threshold value. The state transition condition is satisfied if the feedback is less than the threshold value and not satisfied if the feedback is not less than the threshold value. The method includes transitioning into a pass state in response to the feedback from the temperature sensor satisfying the state transition condition and transitioning into a fail state in response to the feedback from the temperature sensor not satisfying the state transition condition.

Abstract: An adaptive capacity constraint management system receives a measured value affected by HVAC equipment at actual operating conditions and uses the measured value to determine an operating value for a variable that affects a capacity of the HVAC equipment at the actual operating condition. The system uses the operating value to calculate a gain factor for the variable relative to design conditions and uses the calculated gain factor to determine a capacity gain for the HVAC equipment relative to the design conditions. The system applies the capacity gain to a design capacity limit for the HVAC equipment to determine a new capacity limit for the HVAC equipment at the actual operating conditions. The system may use the new capacity limit as a constraint in an optimization routine that that selects one or more devices of the HVAC equipment to satisfy a load setpoint.

Abstract: Systems and methods for auto-commissioning and self-diagnostics of equipment in a building management system are provided. A self-testing module is implemented in a control unit of the building management system. The self-testing module exercises equipment of the building management system using a state-based testing procedure that differs from normal operation of the equipment and monitors feedback received from a sensor of the building management system in response to exercising the equipment. The self-testing module uses the feedback from the sensor to evaluate a state transition condition of the state-based testing procedure and to transition between states of the state-based testing procedure using a result of the evaluation.

Abstract: An adaptive capacity constraint management system receives a measured value affected by HVAC equipment at actual operating conditions and uses the measured value to determine an operating value for a variable that affects a capacity of the HVAC equipment at the actual operating condition. The system uses the operating value to calculate a gain factor for the variable relative to design conditions and uses the calculated gain factor to determine a capacity gain for the HVAC equipment relative to the design conditions. The system applies the capacity gain to a design capacity limit for the HVAC equipment to determine a new capacity limit for the HVAC equipment at the actual operating conditions. The system may use the new capacity limit as a constraint in an optimization routine that that selects one or more devices of the HVAC equipment to satisfy a load setpoint.