A system includes a freezestat assembly that includes a plurality of support brackets disposed in a linear arrangement, and a tubing configured to be disposed in a respective aperture of the each support bracket of the plurality of support brackets, where the tubing is configured to monitor a temperature of a flow of fluid through a heating, ventilating, and air conditioning (HVAC) system, and where the freezestat assembly is configured to be disposed upstream of an evaporator coil of the HVAC system and downstream of a hot water coil of the HVAC system with respect to the flow of fluid through the HVAC system.

A heat pump system may be selectively operated in a defrost mode or cycle. The system includes an energy recovery module that receives and conditions air in a regeneration air channel. A pre-processing module is positioned downstream of the energy recovery module. The pre-processing module receives and heats air from the energy recovery module. A regeneration air heat exchanger is positioned downstream of the pre-processing module. The regeneration air heat exchanger receives and conditions air from the pre-processing module. The pre-processing module heats the air from the energy recovery module to increase an efficiency of the regeneration air heat exchanger. During the defrost mode, a loop of regeneration air may be recirculated between the supply air channel and the regeneration air channel in order to defrost the regeneration air heat exchanger.

Provided are a heat exchanger that does not impede downsizing and removes water in the heat absorbing pipe adequately with a simple configuration even when the reduction in diameter of the heat absorbing pipe is made. A heat exchanger 5 in which heat absorbing pipes 51 are disposed in a multi-tier arrangement within a casing 50 which is the passage of combustion exhaust gas, both pipe ends 511,512 of each of the heat absorbing pipes 51 are connected respectively to two headers 54, 55 provided on a side plate 52 of the casing 50, and water introduced from an external pipe 63 to each of the heat absorbing pipes 51 through the header 54 is heat-exchanged and heated by combustion exhaust gas. The pipe ends 511, 512 of the heat absorbing pipes 51 are arranged at a predetermined vertical interval. A drainage plate 56 for forming a drainage passage through which the water that has reached the pipe end openings 51A of respective heat absorbing pipes 51 is removed during drainage operation for the heat absorbing pipes 51, is disposed in the header 54 disposed on a lower side of the heat absorbing pipes 51 so as to face a number of the pipe end openings 51A vertically arranged in a state of continuous.

A valve and actuator assembly that includes a valve configured to control a flow of liquid into a coil or heat exchanger. The valve and actuator assembly further includes a valve actuator configured to control opening and closing of the valve via positioning of a valve closure member. The valve actuator is further configured to provide both a maximum flow rate and a minimum flow rate of the liquid through the valve. In an embodiment, the valve actuator includes a valve closure member position sensor configured to determine the position of the valve closure member based on a flow rate of the liquid through the valve.

A system and method is described for a heater box or compartment within a gas furnace or other HVAC cabinet. The compartment can house drain hoses, drain traps, and other components used to collect and dispose of condensate. The compartment can comprise heating elements or thermostatic switches to assist in preventing the freezing of condensate.

A control unit includes a scale detection unit for detecting, while the a burner provides combustion, occurrence of clogging with scale in a tube of a heat exchanger, and an output unit for outputting a result of a detection by the scale detection unit, a storage stores information including a numerical value representing how many times a surface temperature of the heat exchanger measured by a temperature measuring unit exceeds at least one of a plurality of threshold values. While the burner provides combustion when the surface temperature measured by the temperature measuring unit exceeds at least one of the plurality of threshold values the scale detection unit adds a predetermined value to the numerical value in the storage and when the numerical value attains a defined value or more the scale detection unit detects occurrence of clogging with scale.

A hybrid heat pump system comprise a geothermal heat pump system, an air source heat pump system, and a buffer heat-storage configured to exchange a heat with the geothermal heat pump system and the air source heat pump system and to store therein the exchanged heat. The buffer heat-storage comprises fluid circulation lines fluid-coupled to and between an air heater and the buffer heat-storage to realize a circulation of a refrigerant fluid therebetween, which receives a heat energy from the buffer heat-storage, wherein the air heater is configured to heat the air thereto from an outdoor using the refrigerant fluid.