A method controls an air handler that generates heated air from hot water generated by a water heater. The method includes generating a signal in the presence or absence of an indicia of water flow associated with the water heater; initiating operation of a pump associated with the air handler when the signal indicates that water flow associated with the water heater is at least at a selected level to supply hot water to the air handler sufficient to generate heated air; and/or terminating operation of the pump and/or a blower/fan associated with the air handler when the presence or absence signal indicates that the water flow associated with the water heater is less than the selected level.

A method controls an air handler that generates heated air from hot water generated by a water heater. The method includes generating a signal in the presence or absence of an indicia of water flow associated with the water heater; initiating operation of a pump associated with the air handler when the signal indicates that water flow associated with the water heater is at least at a selected level to supply hot water to the air handler sufficient to generate heated air; and/or terminating operation of the pump and/or a blower/fan associated with the air handler when the presence or absence signal indicates that the water flow associated with the water heater is less than the selected level.

Disclosed is an air heating apparatus including a burner configured to cause a combustion reaction, a heat exchanging device configured to receive heat from combustion gas generated by the combustion reaction and heat water, a heating heat exchanger configured to receive the water heated by the heat exchanging device and exchange heat with the air for heating, a main passage, in which the heat exchanging device and the heating heat exchanger are disposed, and configured such that the water flows therethrough while circulating, and a fan configured to blow the air to the heating heat exchanger.

There is disclosed an environmental control system for heating at least one enclosed space. The system comprises a heat-pump circuit that includes a compressor, a heat-output stage, an expansion device and an evaporator arranged in series along a flow path for a refrigerant. The heat-output stage comprises a primary heat exchanger and a secondary heat exchanger that are both configured to transfer heat from the refrigerant to one or more external mediums in thermal communication with the at least one enclosed space. The primary heat exchanger and the secondary heat exchanger are connected in series along the flow path, such that the secondary heat exchanger will transfer excess heat energy remaining within the refrigerant after passing through the primary heat exchanger to the one or more external mediums.

A dual heating process is performed in the absence of an open flame. Heat is created by a rotating prime mover(s) driving a fluid shear heater. Heat is also collected from a cooling system of the prime mover, and from any exhaust heat generated by the prime mover. The heat energy collected from all of these sources is transmitted through heat exchangers to a fluid where heat energy is desired. The fluid being heated may be glycol or air, depending on the type of heat desired.

A dual heating process is performed in the absence of an open flame. Heat is created by a rotating prime mover(s) driving a fluid shear heater. Heat is also collected from a cooling system of the prime mover, and from any exhaust heat generated by the prime mover. The heat energy collected from all of these sources is transmitted through heat exchangers to a fluid where heat energy is desired. The fluid being heated may be glycol or air, depending on the type of heat desired.

Air heating and potable water systems have a thermostat with a computer processing unit (CPU), a hot water heater, a hydronic air handler, and a primary pump controlling flow of hot water from the water heater into the hydronic air handler, which has a hydronic coil, a blower, and a first control panel having a CPU in operative communicates with the thermostat. The hydronic coil receives hot water from the water heater to warm air passing over the hydronic coil. The primary pump is in operative communication with the first control panel and an indicator of hot water flow. The indicator of hot water flow is in operative communication with either the thermostat or the first control panel, and any CPU in the system stores a priority instruction, which upon an indication of hot water flow deactivates or delays activation of the primary pump for a predetermined period of time.

Air heating and potable water systems have a thermostat with a computer processing unit (CPU), a hot water heater, a hydronic air handler, and a primary pump controlling flow of hot water from the water heater into the hydronic air handler, which has a hydronic coil, a blower, and a first control panel having a CPU in operative communicates with the thermostat. The hydronic coil receives hot water from the water heater to warm air passing over the hydronic coil. The primary pump is in operative communication with the first control panel and an indicator of hot water flow. The indicator of hot water flow is in operative communication with either the thermostat or the first control panel, and any CPU in the system stores a priority instruction, which upon an indication of hot water flow deactivates or delays activation of the primary pump for a predetermined period of time.

The disclosed technology includes an evaporator having a plurality of sidewalls arranged to define an internal cavity and a top plate covering the internal cavity. At least one of the sidewalls can include a plurality of refrigerant channels such that at least one of the sidewalls can function as a heat exchanger. Each of the refrigerant channels can be attached to a refrigerant inlet and a refrigerant outlet at an angle, such that each refrigerant channel is angled. The angled refrigerant channels can facilitate directing ambient air across the refrigerant channels and fins and to the internal cavity. The angled refrigerant channels can further provide a flow path for accumulated moisture and/or condensate on the exterior surfaces of the refrigerant channels and/or fins to shed, thereby minimizing the potential for freezing.

The disclosed technology includes an evaporator having a plurality of sidewalls arranged to define an internal cavity and a top plate covering the internal cavity. At least one of the sidewalls can include a plurality of refrigerant channels such that at least one of the sidewalls can function as a heat exchanger. Each of the refrigerant channels can be attached to a refrigerant inlet and a refrigerant outlet at an angle, such that each refrigerant channel is angled. The angled refrigerant channels can facilitate directing ambient air across the refrigerant channels and fins and to the internal cavity. The angled refrigerant channels can further provide a flow path for accumulated moisture and/or condensate on the exterior surfaces of the refrigerant channels and/or fins to shed, thereby minimizing the potential for freezing.