Abstract: A modulating heater system for a pool or spa includes a pool or spa heater capable of variably modulating energy output thereof and a controller communicatively coupled thereto. The controller determines a predicted load based on a previous load, ambient and water temperatures, and estimated pool/spa size, and determines an overshoot setpoint for an operational mode. The controller establishes a target temperature setpoint for the mode and receives a current water temperature. The controller determines whether the overshoot setpoint plus target temperature setpoint is greater than the current water temperature, and determines an error based thereon. The controller determines if the error is less than or greater than a target for the mode, and, based on this determination, determines a heater modulation rate for the mode taking into account the mode, maximum heater output, and available fuel supply. The controller controls the heater to operate at the determined modulation rate.

Abstract: Systems and methods for passive and active hybrid defrost control for a pool/spa heat pump are provided. The system monitors the temperature of the evaporator coil of the heat pump and, as required, operates the heat pump in a passive defrost mode if the temperature is less than or equal to a first predetermined temperature value. The system operates the heat pump in an active defrost mode if the temperature of the evaporator coil remains below the first predetermined temperature value and a first time period has expired. The system can stop operation of the active defrost mode when the temperature of the evaporator coil is greater than a second predetermined temperature value. Additionally, the system can stop operation of the passive defrost mode or the active defrost mode upon expiration of a timeout timer.

Abstract: A swimming pool or spa heat pump operable in cooling and heating modes, along with a method of operating same is disclosed. The heat pump includes a compressor, first and second heat exchangers, refrigerant charge compensator, and at least one means for lowering the pressure of refrigerant provided to the first and second heat exchangers. The first heat exchanger is configured to transfer thermal energy to and/or extract thermal energy from a first fluid, and the second heat exchanger is configured to transfer thermal energy to and/or extract thermal energy from pool or spa water. The refrigerant charge compensator is configured to reduce an amount of active refrigerant charge in circulation in the heat pump when the heat pump is operated in the cooling mode and increase the amount of active refrigerant charge in circulation when the heat pump is operated in the heating mode.

Abstract: An inlet mixer system for a gas heater includes a housing in fluid communication with an inlet of a combustion blower, and first and second mixer inserts, each removably positionable within the housing. Each mixer insert includes a body defining a mixing chamber, an air intake, and a plurality of orifices disposed radially about the body and extending through the body, which provide respective volumetric flow rates of a fuel gas. When the first mixer insert is positioned within the housing, the inlet mixer system is configured for use with a first fuel gas, and when the second mixer insert is positioned within the housing, the inlet mixer system is configured for use with a second fuel gas.

Abstract: A modulating heater system for a pool or spa includes a pool/spa heater capable of variably modulating energy output thereof and a controller communicatively coupled to the heater. The controller determines a current mode of operation for the heater, and establishes temperature overshoot and target temperature setpoints for pool/spa water for the current mode of operation. The controller determines a current temperature of the water, an optimized modulation rate for the heater for the current mode of operation, and a maximum modulation rate for the heater for the current mode of operation. The controller controls the heater to operate at one of the optimized and maximum modulation rates based on the temperature overshoot setpoint for the current mode of operation, the target water temperature setpoint for the current mode of operation, and the current water temperature. A corresponding method for controlling a pool/spa modulating heater is also provided.

Abstract: A modulating heater system for a pool or spa includes a pool or spa heater capable of variably modulating energy output thereof and a controller communicatively coupled thereto. The controller determines a predicted load based on a previous load, ambient and water temperatures, and estimated pool/spa size, and determines an overshoot setpoint for an operational mode. The controller establishes a target temperature setpoint for the mode and receives a current water temperature. The controller determines whether the overshoot setpoint plus target temperature setpoint is greater than the current water temperature, and determines an error based thereon. The controller determines if the error is less than or greater than a target for the mode, and, based on this determination, determines a heater modulation rate for the mode taking into account the mode, maximum heater output, and available fuel supply. The controller controls the heater to operate at the determined modulation rate.

Abstract: An inlet mixer system for a gas heater includes a housing in fluid communication with an inlet of a combustion blower, and first and second mixer inserts, each removably positionable within the housing. Each mixer insert includes a body defining a mixing chamber, an air intake, and a plurality of orifices disposed radially about the body and extending through the body, which provide respective volumetric flow rates of a fuel gas. When the first mixer insert is positioned within the housing, the inlet mixer system is configured for use with a first fuel gas, and when the second mixer insert is positioned within the housing, the inlet mixer system is configured for use with a second fuel gas.

Abstract: Swimming pool or spa gas heaters, cabinets, water header manifolds, and heat exchangers include: gas heaters having an air gap between a cabinet and combustion chamber to reduce heat transfer to sides of the cabinet; gas heaters having a user interface that is repositionable on a top panel; gas heater cabinets including a removable top panel that can be hung on a side panel; gas heaters having a built-in dual junction box; gas heaters having a top-accessible igniter and burner that are interlocked to maintain positioning thereof; adaptable water manifolds including connectable inlet and outlet fittings that adjust effective inlet and outlet positions; heat exchangers having a plurality of tube-and-fin subassemblies arranged in a semi-circular configuration; and water manifolds including internal cartridges that divide the water manifold into a plurality of chambers for improved circulation through a heat exchanger are disclosed.

Abstract: Swimming pool or spa gas heaters, cabinets, water header manifolds, and heat exchangers therefor are provided in accordance with the present disclosure, including: gas heaters having an air gap between a cabinet and combustion chamber to reduce heat transfer to sides of the cabinet; gas heaters having a user interface that is repositionable on a top panel; gas heater cabinets including a removable top panel that can be hung on a side panel; gas heaters having a built-in dual junction box; gas heaters having a top-accessible igniter and burner that are interlocked to maintain positioning thereof; adaptable water manifolds including connectable inlet and outlet fittings that adjust effective inlet and outlet positions; heat exchangers having a plurality of tube-and-fin subassemblies arranged in a semi-circular configuration; and water manifolds including internal cartridges that divide the water manifold into a plurality of chambers for improved circulation through a heat exchanger are disclosed.