Systems and methods for defrost of heat pump systems
AssigneeGoodman Manufacturing Company, L.P.
InventorsMichael F. Taras, David L. Boyea
Life of this patent
Estimating the term…
Abstract
The present disclosure relates to a heating, ventilation, and air conditioning (“HVAC”) system include a supply damper, a return damper, and a defrost damper which are operable to control a supply airflow, a return airflow, and a defrost airflow to flow between a supply duct, a return duct, and an indoor heat exchanger without substantially flowing into and substantially cooling an indoor space. A reheat coil may also warm the supply air flow and a defrost return line may be used to bypass a bi-flow expansion device and an indoor heat exchanger.
Claims12
A heating, ventilation, and air conditioning (HVAC) system operable to use a refrigerant to heat or cool an indoor space and comprising:
- a compressor, an outdoor heat exchanger, an indoor heat exchanger, a bi-flow expansion device, and a four-way valve operable to flow the refrigerant through the bi-flow expansion device in a first direction in a cooling mode and in a second direction, opposite the first direction, in a heating mode;
- a reheat coil positioned in line with an airflow passing across the indoor heat exchanger;
- and
- a three-way valve positioned between the compressor and the four-way valve;
- wherein in a defrost mode:
- the four-way valve is operable to direct the refrigerant flow in the first direction through the outdoor heat exchanger to defrost the outdoor heat exchanger;
- and
- the three-way valve is operable to flow at least a portion of refrigerant, which is warm and compressed, from the compressor to the reheat coil so that a supply airflow from the indoor heat exchanger to the indoor space is warmed.
A heating, ventilation, and air conditioning (HVAC) system operable to use a refrigerant to heat or cool an indoor space and comprising:
- a compressor, an outdoor heat exchanger, an indoor heat exchanger, a bi-flow expansion device, and a four-way valve operable to flow the refrigerant in a refrigeration circuit through the bi-flow expansion device in a first direction in a cooling mode and in a second direction, opposite the first direction, in a heating mode;
- and
- a three-way valve located in the refrigeration circuit between the outdoor heat exchanger and the bi-flow expansion device;
- wherein in a defrost mode:
- the four-way valve is operable to direct the refrigerant flow in the first direction through the outdoor heat exchanger to defrost the outdoor heat exchanger;
- and
- the three-way valve is operable to direct the refrigerant flow from the outdoor heat exchanger through a defrost return line and a defrost expansion device to the compressor and thereby bypass the bi-flow expansion device and the indoor heat exchanger.
A method of defrosting a heating, ventilation, and air conditioning (“HVAC”) system operable to use a refrigerant to heat or cool an indoor space, the method comprising:
- compressing the refrigerant with a compressor;
- flowing warmed and compressed refrigerant from the compressor through a four-way valve and an outdoor heat exchanger to defrost the outdoor heat exchanger;
- and
- flowing a supply airflow across an indoor heat exchanger while not cooling the indoor space.
Dependencies are inferred from the claim text.