US-12624872-B2 - Heat pump system and components thereof

US12624872B2US 12624872 B2US12624872 B2US 12624872B2US-12624872-B2

Abstract

A heat pump system is provided. The heat pump system includes a refrigerant circuit through which a refrigerant is caused to flow and an antifreeze circuit through which an antifreeze solution is caused to flow having an antifreeze accumulator tank. The refrigerant circuit includes a first refrigerant coil arranged within a first heat exchanger and a second refrigerant coil arranged within a second heat exchanger. The antifreeze accumulator tank heats an antifreeze solution. The antifreeze circuit includes an antifreeze coil arranged within the first heat exchanger and proximate to the first refrigerant coil such that the antifreeze coil heats the first refrigerant coil. In some examples, the antifreeze accumulator tank includes a controllable heater arranged to heat the antifreeze solution. In other examples, the refrigerant circuit further includes a third refrigerant coil arranged within the antifreeze accumulator tank such that the third refrigerant coil heats the antifreeze solution.

Inventors

Lorenzo H. Rossi

Assignees

Terravis Energy, Inc.

Dates

Publication Date: 20260512
Application Date: 20250728

Claims (19)

1 . A heat pump system, comprising: a refrigerant circuit through which a refrigerant is caused to flow, wherein the refrigerant circuit comprises: a first refrigerant coil arranged within a first heat exchanger; and a second refrigerant coil arranged within a second heat exchanger; an antifreeze circuit through which an antifreeze solution is caused to flow, comprising: an antifreeze accumulator tank configured to heat the antifreeze solution; and an antifreeze coil arranged within the first heat exchanger and proximate to the first refrigerant coil such that the antifreeze coil regulates a temperature of the first refrigerant coil, wherein the first heat exchanger comprises an external coil layer and at least one internal coil layer, wherein the antifreeze coil is arranged within the external coil layer, and wherein the first refrigerant coil is arranged within the at least one internal coil layer, wherein the first refrigerant coil and the antifreeze coil are eccentric to each other, whereby the heat pump system is configured to operate continuously without entering a defrost cycle, without compressor stall, and/or without refrigerant lock-up at an outdoor ambient temperature below about −5° F.
2 . The heat pump system of claim 1 , wherein the antifreeze accumulator tank comprises a controllable heater arranged to heat the antifreeze solution.
3 . The heat pump system of claim 2 , wherein the antifreeze accumulator tank further comprises a temperature sensor configured to generate a temperature signal, and wherein a temperature of the controllable heater is controlled based on the temperature signal.
4 . The heat pump system of claim 3 , wherein the temperature of the controllable heater ranges from 180° F. to 200° F.
5 . The heat pump system of claim 2 , further comprising an ambient temperature sensor configured to capture the outdoor ambient temperature, wherein the controllable heater is deactivated if the outdoor ambient temperature is greater than about 68° F.
6 . The heat pump system of claim 1 , wherein the refrigerant circuit further comprises a third refrigerant coil arranged within the antifreeze accumulator tank such that the third refrigerant coil heats the antifreeze solution.
7 . The heat pump system of claim 1 , wherein a freezing point of the antifreeze solution is less than or equal to about −30° F.
8 . The heat pump system of claim 1 , wherein a boiling point of the antifreeze solution is greater than or equal to about 200° F.
9 . The heat pump system of claim 1 , wherein the antifreeze solution comprises silicone oil.
10 . The heat pump system of claim 1 , wherein the heat pump system is configured to operate continuously without entering a defrost cycle, without compressor stall, and/or without refrigerant lock-up at the outdoor ambient temperature as low as about −56.9° F.
11 . The heat pump system of claim 1 , wherein the heat pump system comprises a cooling mode, in which the antifreeze coil is configured to be a heat sink that prevents hot spot formation on the first refrigerant coil up to an ambient temperature of about 86° F.
12 . The heat pump system of claim 1 , wherein the first heat exchanger is configured to be arranged in an outdoor environment, and the second heat exchanger is configured to be arranged in an indoor environment.
13 . The heat pump system of claim 1 , further comprising an antifreeze fluid pump configured to propel the antifreeze solution through the antifreeze circuit, wherein the antifreeze fluid pump has a pump speed of at least about 5.2 gallons per minute.
14 . The heat pump system of claim 13 , further comprising: a controllable heater arranged to heat the antifreeze solution; and a controller configured to receive an ambient temperature and the temperature of the first refrigerant coil and to modulate the controllable heater and the antifreeze fluid pump.
15 . A heat exchanger configured to be installed in a heat pump system, the heat exchanger comprising: a refrigerant circuit through which a refrigerant is caused to flow, wherein the refrigerant circuit comprises a refrigerant coil; an antifreeze circuit through which an antifreeze solution is caused to flow, wherein the antifreeze circuit comprises: an antifreeze accumulator tank configured to heat the antifreeze solution, and an antifreeze coil arranged proximate to the refrigerant coil such that the antifreeze coil regulates a temperature of the refrigerant coil, an internal coil layer within which the refrigerant coil is arranged; and an external coil layer within which the antifreeze coil is arranged, wherein the refrigerant coil and the antifreeze coil are eccentric to each other.
16 . A heat pump system, comprising: a refrigerant circuit through which a refrigerant is caused to flow, wherein the refrigerant circuit comprises a refrigerant coil arranged within an outdoor heat exchanger; and an antifreeze circuit through which an antifreeze solution is caused to flow, wherein the antifreeze circuit includes an antifreeze coil arranged within the outdoor heat exchanger and proximate to the refrigerant coil to (i) prevent frost formation on the refrigerant coil in ambient outdoor temperatures lower than about −5° F. and (ii) prevent hot spot formation in ambient outdoor temperatures from about 68° F. to about 86° F., wherein the outdoor heat exchanger comprises an external coil layer and an internal coil layer, the antifreeze coil is arranged within the external coil layer, and the refrigerant coil is arranged within the internal coil layer, wherein the refrigerant coil and the antifreeze coil are eccentric to each other.
17 . The heat pump system of claim 16 , wherein a freezing point of the antifreeze solution is less than or equal to about −30° F.
18 . The heat pump system of claim 16 , wherein a boiling point of the antifreeze solution is greater than or equal to about 200° F.
19 . The heat pump system of claim 16 , wherein a boiling point of the refrigerant is less than or equal to −50° F.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application Ser. No. 63/704,764, entitled “Heat Pump System and Components Thereof,” filed on Oct. 8, 2024, which application is hereby incorporated by reference in its entirety. FIELD OF THE DISCLOSURE This disclosure relates, generally, to heat pumps, and more specifically, to a heat pump system having an antifreeze mechanism to prevent frost from forming on an outdoor heat exchanger. BACKGROUND Heat pumps are energy-efficient alternatives to furnaces and air conditioners. Air-source heat pumps provide heat to an interior of a building by pulling heat from outdoor air and transferring it indoors. Accordingly, heat pumps require both an outdoor heat exchanger and an indoor heat exchanger to facilitate this transfer. One disadvantage to conventional air-source heat pumps is that in cold outdoor conditions, frost can form on the outdoor unit. This frost can prevent the heat pump from efficiently pulling heat from the outdoor air. Thus, currently available heat pumps are configured to enter a defrost cycle when frost has formed on the outdoor unit. While the defrost cycle may reduce the amount of frost, these heat pumps stop producing heat during the defrost cycle. Further, the defrost cycle reduces the energy efficiency of the heat pump by diverting energy for purposes other than heating the interior of the building. The present disclosure advantageously addresses one or more of the problems and deficiencies of the heat pumps discussed above. However, it is contemplated that the subject matter of the disclosure may prove useful in addressing other problems and deficiencies in a number of technical areas. Therefore, the present disclosure should not necessarily be construed as limited to addressing any of the particular problems or deficiencies discussed herein. In this specification, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge, or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which this specification is concerned. SUMMARY OF THE DISCLOSURE The present disclosure is generally directed to a heat pump system for use in cold weather environments. Broadly, the heat pump system includes a dual circuit configuration (which may also be referred to as a dual path configuration) to prevent frost formation at very low temperatures, thereby avoiding the need to run inefficient defrost cycles when heating is required. The heat pump system includes a refrigerant circuit (which may also be referred to as a refrigerant path), an antifreeze circuit (which may also be referred to as an antifreeze path) having an antifreeze accumulator tank, an outdoor heat exchanger, and an indoor heat exchanger. The refrigerant circuit is configured to circulate refrigerant (e.g., R32, R454B, or R452B refrigerants) to different aspects of the heat pump system. The refrigerant circuit includes a first refrigerant coil arranged within the outdoor heat exchanger, and a second refrigerant coil arranged within the indoor heat exchanger. Similarly, the antifreeze circuit is configured to circulate an antifreeze solution. The antifreeze solution is heated as it is stored and cycled through the antifreeze accumulator tank. The antifreeze circuit includes an antifreeze coil arranged within the outdoor heat exchanger. The antifreeze coil is arranged proximate to the first refrigerant coil, such that the antifreeze coil heats the first refrigerant coil to prevent the formation of frost. This arrangement may prevent the formation of frost at outdoor temperatures of −5° F. and lower, preferably −10° F. and lower, down to about −30° F. or even down to about −50° F. In one embodiment, a controllable heater, such as an electric rod is arranged within the antifreeze tank to heat the antifreeze solution. Further, a temperature sensor is also arranged within the antifreeze tank. A temperature signal provided by the temperature sensor is used to regulate the temperature of the controllable heater. The temperature of the controllable heater may vary from 180° F. to 200° F., for example. In further examples, the controllable heater may be deactivated at certain ambient outdoor temperatures when the heater is a heat pump system functioning in a cooling mode, rather than heating mode, resulting in unheated, ambient temperature antifreeze solution. Circulating the ambient temperature antifreeze solution allows the antifreeze coil to function as a heat sink to regulate the temperature of the first refrigerant coil, preventing the formation of hot spots on the first refrigerant coil at high ambient outdoor temperatures. In alternate