Air conditioner and cold air prevention control method thereof

Abstract

The invention discloses an air conditioner and a cold air prevention control method thereof. The air conditioner comprises an indoor unit, an outdoor unit, an electric heating detection circuit and a controller. The electric heating detection circuit is used for detecting whether electric heating exists or not and comprises a first loop, a second loop and a zero-crossing monitoring loop. The controller is configured to judge whether electric heating exists or not when the air conditioner is in a heating mode and if it is detected that the first loop is closed and the second loop is connected with the zero-crossing monitoring loop, the electric heating is started, and the indoor fan is controlled to run at a strong wind gear. And if it is detected that the first loop is disconnected and the second loop and the zero-crossing monitoring loop are not connected, it is judged that electric heating does not exist, and the indoor fan is turned off. The electric heating detection circuit is arranged to judge whether the machine has electric heating or not, under the condition that electric heating exists, electric heating is actively started, cold air prevention control logic is not operated, the continuous heating experience of a user is greatly improved, and no matter whether the machine is defrosted or not, hot air is blown to the indoor side all the time.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning, and in particular to an air conditioner and a cold wind prevention control method thereof. Background Art

[0002] The optional electric heaters on North American replacement units or rooftop units often have higher power. For example, a 36K rooftop unit has a heating capacity of 10.5kW, while optional electric heaters often have a heating capacity of over 15kW. These heaters are powered separately and connected to the electric heater's air switch via a relay on the interior unit board, thereby controlling the high-voltage circuit with a low-voltage circuit. Electric heaters are typically optional in North American replacement units and rooftop units. Without electric heaters, the air conditioner has a cold air prevention function that stops the indoor fan during heating startup and during heating and defrosting. Models with electric heaters also implement this logic. Specifically, when the indoor unit board sends a signal to start the electric heater, the relay often activates, but the subsequent feedback from the circuit regarding the presence or absence of electric heaters is lost. Consequently, the cold air prevention function is implemented, or the fan continues to operate during defrosting, blowing cold air. This results in intermittent heating and a poor user experience. Summary of the Invention

[0003] The present invention provides an air conditioner and a cold wind prevention control method thereof. An electric heating detection circuit is provided to determine whether the machine has electric heating. If electric heating is provided, the electric heating is actively turned on and the cold wind prevention control logic is not run, thereby greatly improving the user's continuous heating experience. Regardless of whether the machine is defrosted or not, hot air is always blown indoors.

[0004] The air conditioner provided in the first embodiment of the present invention includes:

[0005] The indoor unit is used to exchange heat with the indoor air and is equipped with an indoor heat exchanger and an indoor fan;

[0006] The outdoor unit is used to exchange heat with outdoor air, and is equipped with an outdoor heat exchanger, an outdoor fan, a compressor, a flow regulating valve and a four-way valve. The compressor, the flow regulating valve, the four-way valve, the outdoor heat exchanger and the indoor heat exchanger are connected by pipelines to form a refrigerant circulation loop;

[0007] The electric heating detection circuit is used to detect whether electric heating exists, and includes a first circuit, a second circuit, and a zero-crossing monitoring circuit;

[0008] The controller is configured such that, when the air conditioner is in heating mode, if it is detected that the first circuit is closed and the second circuit is connected to the zero-crossing monitoring circuit, it is determined that electric heating is present, the electric heating is started, and the indoor fan is controlled to run at a high wind speed; if it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that electric heating is not present and the indoor fan is turned off.

[0009] In the air conditioner provided by the second embodiment of the present invention, the controller is further configured to:

[0010] When it is determined that electric heating is present, if a first signal of the first circuit or a second signal of the second circuit is detected, the first level electric heating is turned on;

[0011] If the first signal of the first circuit and the second signal of the second circuit are detected, the secondary electric heating is turned on.

[0012] In the air conditioner provided by the third embodiment of the present invention, the controller is further configured to:

[0013] When it is determined that electric heating is present, if it is detected that the outdoor ambient temperature is less than a first temperature threshold, the secondary electric heating is forcibly turned on, and the outdoor fan is controlled to stop running.

[0014] In the air conditioner provided by the fourth embodiment of the present invention, the controller is further configured to:

[0015] When it is determined that electric heating is present, if it is detected that the air conditioner satisfies any one of the preset conditions, the electric heating is turned off; wherein the preset conditions are:

[0016] The air conditioner is in non-heating mode;

[0017] The indoor ambient temperature is greater than a second temperature threshold;

[0018] The indoor fan stops running;

[0019] The compressor stops running;

[0020] The indoor coil temperature is greater than a third temperature threshold for a continuous preset time;

[0021] The outdoor ambient temperature is greater than a fourth temperature threshold;

[0022] The first signal of the first loop and the second signal of the second loop are not detected.

[0023] In the air conditioner provided in the fifth embodiment of the present invention, the controller is further configured to:

[0024] When the electric heating is turned off, the indoor fan is controlled to exit the strong wind gear and operate at the corresponding wind gear according to the set temperature.

[0025] A sixth embodiment of the present invention provides an air conditioner cold wind prevention control method, which is applied to an air conditioner including an indoor heat exchanger, an indoor fan, an outdoor heat exchanger, an outdoor fan, a compressor, a flow control valve, a four-way valve, and an electric heating detection circuit, wherein the electric heating detection circuit is used to detect whether electric heating is present and includes a first circuit, a second circuit, and a zero-crossing monitoring circuit. The air conditioner cold wind prevention control method includes:

[0026] When the air conditioner is in heating mode, if it is detected that the first circuit is closed and the second circuit is connected to the zero-crossing monitoring circuit, it is determined that electric heating is present, the electric heating is started, and the indoor fan is controlled to operate at a strong wind speed;

[0027] If it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that there is no electric heating and the indoor fan is turned off.

[0028] In the air conditioner cold wind prevention control method provided in the seventh embodiment of the present invention, the method further includes:

[0029] When it is determined that electric heating is present, if a first signal of the first circuit or a second signal of the second circuit is detected, the first level electric heating is turned on;

[0030] If the first signal of the first circuit and the second signal of the second circuit are detected, the secondary electric heating is turned on.

[0031] In the air conditioner cold wind prevention control method provided in the eighth embodiment of the present invention, the method further includes:

[0032] When it is determined that electric heating is present, if it is detected that the outdoor ambient temperature is less than a first temperature threshold, the secondary electric heating is forcibly turned on, and the outdoor fan is controlled to stop running.

[0033] In the cold wind prevention control method for an air conditioner provided in a ninth embodiment of the present invention, the method further comprises:

[0034] When it is determined that electric heating is present, if it is detected that the air conditioner satisfies any one of the preset conditions, the electric heating is turned off; wherein the preset conditions are:

[0035] The air conditioner is in non-heating mode;

[0036] The indoor ambient temperature is greater than a second temperature threshold;

[0037] The indoor fan stops running;

[0038] The compressor stops running;

[0039] The indoor coil temperature is greater than a third temperature threshold for a continuous preset time;

[0040] The outdoor ambient temperature is greater than a fourth temperature threshold;

[0041] The first signal of the first loop and the second signal of the second loop are not detected.

[0042] In the cold wind prevention control method for an air conditioner provided in the tenth embodiment of the present invention, the method further includes:

[0043] When the electric heating is turned off, the indoor fan is controlled to exit the strong wind gear and operate at the corresponding wind gear according to the set temperature.

[0044] Compared to the prior art, the air conditioner and its cold wind prevention control method provided by the embodiments of the present invention have the following advantages: by setting an electric heating detection circuit to determine whether the machine has electric heating, the electric heating detection circuit includes a first circuit, a second circuit, and a zero-crossing monitoring circuit; when the air conditioner is in heating mode, if it is detected that the first circuit is closed and the second circuit is connected to the zero-crossing monitoring circuit, it is determined that electric heating is present, the electric heating is started, and the indoor fan is controlled to operate at a high wind speed; if it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that electric heating is not present and the indoor fan is turned off. In the case of electric heating, the embodiments of the present invention actively turn on the electric heating and do not run the cold wind prevention control logic. Since the electric heating power optional in North America is often larger, the heat from the electric heating can completely cover the cold air blown out during the machine startup phase or defrost phase, greatly improving the user's continuous heating experience. Regardless of whether the machine is defrosted, hot air is always blown indoors. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a perspective view of the appearance of an air conditioner provided by one embodiment of the present invention;

[0046] Figure 2 This is a structural diagram of an air conditioner provided by one embodiment of the present invention;

[0047] Figure 3 This is a schematic diagram of a refrigerant circulation circuit of an air conditioner provided by one embodiment of the present invention;

[0048] Figure 4 1 is a schematic diagram of an electric heating detection circuit in an air conditioner provided by one embodiment of the present invention;

[0049] Figure 5 This is a schematic diagram of electric heating entry conditions in an air conditioner provided by one embodiment of the present invention;

[0050] Figure 6 This is a first working flow diagram of a controller in an air conditioner provided by one embodiment of the present invention;

[0051] Figure 7 This is a second working flow diagram of a controller in an air conditioner provided by one embodiment of the present invention;

[0052] Figure 8 This is a third working flow diagram of a controller in an air conditioner provided by one embodiment of the present invention;

[0053] Figure 9 This is a fourth working flow diagram of a controller in an air conditioner provided by one embodiment of the present invention;

[0054] Figure 10 The present invention is a flowchart of an air conditioner cold wind prevention control method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0056] In the description of this application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0057] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. Throughout this application, unless otherwise specified, "plurality" means two or more.

[0058] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0059] See also Figures 1 to 2 , Figure 1 This is a perspective view of the appearance of an air conditioner provided by one embodiment of the present invention. Figure 2 FIG1 is a schematic diagram of the structure of an air conditioner provided in one embodiment of the present invention. The air conditioner 1 provided in the embodiment of the present invention comprises:

[0060] The indoor unit 2 is used for heat exchange with indoor air and is equipped with an indoor heat exchanger 21 and an indoor fan 22;

[0061] The outdoor unit 3 is used to exchange heat with outdoor air and includes an outdoor heat exchanger 31, an outdoor fan 32, a compressor 33, a flow regulating valve 34, and a four-way valve 35. The compressor 33, the flow regulating valve 34, the four-way valve 35, the outdoor heat exchanger 31, and the indoor heat exchanger 21 are connected by pipelines to form a refrigerant circulation loop.

[0062] The electric heating detection circuit is used to detect whether electric heating exists, and includes a first circuit, a second circuit, and a zero-crossing monitoring circuit;

[0063] The controller is configured such that, when the air conditioner is in heating mode, if it is detected that the first circuit is closed and the second circuit is connected to the zero-crossing monitoring circuit, it is determined that electric heating exists, the electric heating is started, and the indoor fan 22 is controlled to run at a high wind speed; if it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that electric heating does not exist and the indoor fan 22 is turned off.

[0064] Specifically, the air conditioner 1 in the embodiment of the present invention includes an indoor unit 2. Taking the indoor wall mounted unit (shown in the figure) as an example, the indoor wall mounted unit is usually installed on the indoor wall. For another example, the indoor cabinet unit (not shown in the figure) is also a form of indoor unit. The outdoor unit 3 is usually installed outdoors and is used for heat exchange in the indoor environment. In addition, Figure 1In the illustration, the outdoor unit 3 is shown with a dashed line because it is located outdoors on the opposite side of the indoor unit 2, separated by a wall. The indoor unit 2 and the outdoor unit 3 are connected by a connecting pipe 4. The indoor unit 2 houses an indoor heat exchanger 21 and an indoor fan 22. The indoor heat exchanger 21 consists of a plurality of fins and a coil extending through the fins. Depending on the operating state of the indoor unit 2, the indoor heat exchanger 21 functions as an evaporator or a radiator, exchanging heat between the refrigerant flowing through the coil and the air passing through the indoor heat exchanger 21. The indoor fan 22 is located approximately in the center of the indoor unit casing. It is a cross-flow fan that is elongated in the longitudinal direction (left-right direction) of the indoor unit 2. As the indoor fan 22 rotates, indoor air is drawn in through the air inlet, passes through the air filter, and then passes through the indoor heat exchanger 21. The resulting conditioned air is then blown out through the outlet into the room. The higher the speed of the indoor fan 22, the greater the volume of conditioned air blown out of the outlet. When the air conditioner is in cooling mode, the indoor heat exchanger 21 operates as an evaporator. Depending on the operating status of the indoor unit, the indoor heat exchanger 21 functions as either an evaporator or a radiator, exchanging heat between the refrigerant flowing through the heat transfer tubes and the air passing through the indoor heat exchanger. The indoor fan 22 generates an airflow of indoor air through the indoor heat exchanger 21 to facilitate heat exchange between the refrigerant flowing through the heat transfer tubes of the indoor heat exchanger 21 and the indoor air. The outdoor unit 3 includes an outdoor heat exchanger 31, an outdoor fan 32, a compressor 33, a flow control valve 34, and a four-way valve 35. The outdoor fan 32 generates an airflow of outdoor air through the outdoor heat exchanger 31 to facilitate heat exchange between the refrigerant flowing through the heat transfer tubes and the outdoor air. The outdoor fan 32 is driven by an outdoor motor with a variable speed. When the air conditioner is in cooling mode, the outdoor heat exchanger 31 operates as a condenser. The outdoor fan 32 generates an airflow of outdoor air through the outdoor heat exchanger 31 to promote heat exchange between the refrigerant flowing in the heat transfer tubes of the outdoor heat exchanger 31 and the outdoor air.

[0065] See also Figure 3 , Figure 3The figure is a schematic diagram of a refrigerant circulation circuit for an air conditioner provided in one embodiment of the present invention. A compressor 33, a flow control valve 34, a four-way valve 35, an outdoor heat exchanger 31, and an indoor heat exchanger 21 are connected by pipes to form a refrigerant circulation circuit. The indoor heat exchanger 21 and the outdoor heat exchanger 31 function as a condenser or an evaporator. When the indoor heat exchanger 21 functions as a condenser and the outdoor heat exchanger 31 functions as an evaporator, the air conditioner functions as a heater in heating mode; when the indoor heat exchanger 21 functions as an evaporator and the outdoor heat exchanger 31 functions as a condenser, the air conditioner functions as a cooler in cooling mode. The four-way valve 35 is used to control the flow direction of the refrigerant in the refrigerant circulation circuit, so that the outdoor heat exchanger and the indoor heat exchanger can switch between functioning as a condenser and an evaporator. When the air conditioner is in cooling mode, the indoor heat exchanger 21 and the outdoor heat exchanger 31 function as an evaporator and a condenser, respectively. The refrigerant is compressed by the compressor and transformed into a high-temperature, high-pressure gas. It then passes through a four-way valve and enters the outdoor heat exchanger of the outdoor unit. There, it absorbs cold air and releases heat, becoming a medium-temperature, high-pressure liquid. After passing through a flow control valve, it becomes a low-temperature, low-pressure liquid. After absorbing heat and releasing heat in the indoor heat exchanger of the indoor unit, it becomes a low-temperature, low-pressure gas. It then passes through the four-way valve and returns to the compressor, continuing its cycle. The refrigerant circulation in the refrigerant circuit enables a vapor compression refrigeration cycle. The flow control valve can change its opening. Reducing the opening increases the flow resistance of the refrigerant through the flow control valve, while increasing the opening decreases the flow resistance. During cooling operation, this flow control valve expands and decompresses the refrigerant flowing from the indoor heat exchanger to the outdoor heat exchanger. Furthermore, even if the conditions of other components in the refrigerant circuit remain unchanged, changes in the opening of the flow control valve can change the flow rate of the refrigerant flowing through the refrigerant circuit.

[0066] See also Figure 4 , Figure 4This is a schematic diagram of an electric heating detection circuit in an air conditioner provided by one embodiment of the present invention. This embodiment of the present invention detects whether the air conditioner has electric heating by providing an electric heating detection circuit. The electric heating detection circuit includes a first circuit, a second circuit, and a zero-crossing monitoring circuit. If electric heating is present, the first circuit is closed, the second circuit is connected to the zero-crossing monitoring circuit, and the second circuit can send a second signal to the zero-crossing monitoring circuit. If electric heating is not present, the first circuit is disconnected, the second circuit is not connected to the zero-crossing monitoring circuit, and the second circuit cannot send the second signal to the zero-crossing monitoring circuit. Based on the above principles, the controller of this embodiment of the present invention is configured such that when the air conditioner is in heating mode, if the first circuit is closed and the second circuit is connected to the zero-crossing monitoring circuit, it determines that electric heating is present. In this case, the cold air prevention control logic is not required, and the electric heating is directly activated. The indoor fan is controlled to operate at the high speed setting, that is, the indoor fan speed is adjusted to the maximum speed and the set temperature is set to the ambient temperature + 4°C. It should be noted that as long as the air conditioner is in heating mode, the electric heating is activated at the high speed setting, regardless of whether the defrost function is in progress. If it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that there is no electric heating. At this time, it is necessary to run the common anti-cold wind control logic of existing models, turn off the indoor fan, and run a breeze when it is detected that the indoor coil temperature is between fixed temperatures 1 and 2. When it is detected that the indoor coil temperature reaches above fixed temperature 2, it starts normally and the anti-cold wind ends.

[0067] The embodiment of the present invention determines whether the machine has electric heating by setting an electric heating detection circuit. If electric heating is available, the electric heating is actively turned on and the anti-cold wind control logic is not run. Since the electric heating power optional in North America is often large, the heat from the electric heating can completely cover the cool air blown out during the machine startup phase or defrosting phase, greatly improving the user's continuous heating experience. Regardless of whether the machine is defrosted or not, hot air is always blown indoors.

[0068] As one of the optional embodiments, the controller is further configured to:

[0069] When it is determined that electric heating is present, if a first signal of the first circuit or a second signal of the second circuit is detected, the first level electric heating is turned on;

[0070] If the first signal of the first circuit and the second signal of the second circuit are detected, the secondary electric heating is turned on.

[0071] For details, please refer to Figure 5 and Figure 6 , Figure 5 This is a schematic diagram of electric heating entry conditions in an air conditioner provided by one embodiment of the present invention. Figure 6This is a first operational flowchart of a controller in an air conditioner provided by one embodiment of the present invention. After determining that electric heating is in operation, this embodiment of the present invention determines the electric heating level based on the first signal (W1) in the first circuit and the second signal (W2) in the second circuit of the electric heating detection circuit. If either the first signal (W1) or the second signal (W2) is detected, first-stage electric heating is activated. That is, as long as either signal (W1) or (W2) is detected, only first-stage electric heating is activated. If both the first signal (W1) and the second signal (W2) are detected, second-stage electric heating is activated. That is, both signals (W1 and W2) must be detected simultaneously for second-stage electric heating to be activated. It should be noted that the condition for deactivating first-stage electric heating is the absence of both the W1 and W2 signals, as the presence of either signal activates first-stage electric heating. The condition for deactivating second-stage electric heating is: if either the W1 or W2 signal disappears, first-stage electric heating control is activated; if both the W1 and W2 signals disappear, electric heating is completely deactivated.

[0072] As one of the optional embodiments, the controller is further configured to:

[0073] When it is determined that electric heating is present, if it is detected that the outdoor ambient temperature is less than a first temperature threshold, the secondary electric heating is forcibly turned on, and the outdoor fan is controlled to stop running.

[0074] For details, please refer to Figure 7 , Figure 7 This is a second workflow diagram for a controller in an air conditioner provided by one embodiment of the present invention. In this embodiment of the present invention, when electric heating is determined to be present, if the outdoor ambient temperature is detected to be less than a first temperature threshold (for example, less than -20°C), and the air conditioner is in heating mode, the secondary electric heating is forcibly activated, the outdoor fan is stopped, and the indoor fan is operated at a high speed setting. Because low outdoor temperatures can cause compressor pressure indicators to exceed the compressor's specifications, long-term damage can occur, and the compressor oil and refrigerant can stratify at very low temperatures.

[0075] As one of the optional embodiments, the controller is further configured to:

[0076] When it is determined that electric heating is present, if it is detected that the air conditioner satisfies any one of the preset conditions, the electric heating is turned off; wherein the preset conditions are:

[0077] The air conditioner is in non-heating mode;

[0078] The indoor ambient temperature is greater than a second temperature threshold;

[0079] The indoor fan stops running;

[0080] The compressor stops running;

[0081] The indoor coil temperature is greater than a third temperature threshold for a continuous preset time;

[0082] The outdoor ambient temperature is greater than a fourth temperature threshold;

[0083] The first signal of the first loop and the second signal of the second loop are not detected.

[0084] For details, please refer to Figure 8 , Figure 8 This is a third working flow diagram of a controller in an air conditioner provided by one embodiment of the present invention. In this embodiment of the present invention, when it is determined that electric heating is present, if it is detected that the air conditioner meets any one of the preset conditions, the electric heating is turned off. The preset conditions are:

[0085] The air conditioner is in non-heating mode; because when the air conditioner is in cooling mode, it is necessary to prevent cold wind.

[0086] The indoor ambient temperature is greater than the second temperature threshold; because when the indoor ambient temperature is high, the heating capacity of the machine itself can already meet the user's needs. At this time, if the electric heating is turned on, it will waste electricity resources. Secondly, the air outlet temperature will be very high, resulting in poor user comfort.

[0087] Stop the indoor fan. When the indoor fan stops, it no longer circulates air. If the electric heater is turned on at this time, the heat will not be effectively dissipated, which may cause local overheating and even pose a safety hazard. Also, without the fan circulating the air, the heat generated by the electric heater cannot be evenly distributed throughout the room, thus failing to effectively raise the indoor temperature.

[0088] The compressor stops running; when the compressor stops, the heating cycle also stops, and the system no longer requires additional heating. Secondly, turning on electric heating when the compressor stops can increase energy consumption. This is because electric heating consumes energy to generate heat, and when the compressor is stopped, this heat may not be effectively utilized, resulting in energy waste.

[0089] The indoor coil temperature is greater than the third temperature threshold for a continuous preset time. When the indoor coil temperature is greater than the third temperature threshold for a continuous preset time, it indicates that the heating capacity of the machine itself has already met the user's needs. At this time, if electric heating is turned on again, it will waste electricity resources. Secondly, the air outlet temperature will be very high, resulting in poor user comfort.

[0090] The outdoor ambient temperature is greater than the fourth temperature threshold. This indicates a relatively warm environment, which helps maintain a comfortable indoor temperature. In this case, the temperature difference between indoor and outdoor is small, and heat exchange is relatively smooth, so additional electric heating is not required to raise the indoor temperature. Secondly, electric heating is primarily used to supplement indoor heat, especially when the outdoor temperature is low and the indoor temperature is difficult to maintain. When the outdoor temperature is higher, the indoor temperature can usually be maintained at a comfortable level through natural convection or other heating methods in the system (such as heat generated by compressor operation), eliminating the need for additional electric heating. Furthermore, from an energy utilization perspective, activating electric heating when the outdoor temperature is high results in unnecessary energy waste. Electric heating consumes energy to generate heat, and when the outdoor temperature is high, this heat may not be fully utilized, resulting in low energy efficiency. Finally, frequently activating electric heating may negatively impact system stability and lifespan. When the outdoor temperature is high, the system may already be operating in a relatively stable state. Activating electric heating at this time may disrupt system balance, increase system burden, and even cause failure or damage.

[0091] The first signal of the first circuit and the second signal of the second circuit are not detected; because as long as one signal exists, the first level electric heating will be turned on, and the electric heating will not be turned off until both the first signal and the second signal disappear.

[0092] For example, electric heating enters condition 1: (when the following conditions are met at the same time)

[0093] Heating or automatic heating mode operation;

[0094] Return air T<25℃;

[0095] The compressor is running;

[0096] The indoor unit fan is running;

[0097] Indoor coil temperature <53°C;

[0098] Non-defrost operating time;

[0099] There is no fault in the internal unit;

[0100] Receive the W1 signal or W2 signal sent by the wired controller.

[0101] Execute action:

[0102] The indoor fan is forced to operate at high speed;

[0103] The electric heating related relay is energized and the first-level electric heating is started.

[0104] Exit conditions: (Meet any of the following conditions)

[0105] Mode switched to non-heating mode;

[0106] Indoor ambient temperature Troom>30℃;

[0107] The indoor fan stops running;

[0108] The compressor stops running;

[0109] Indoor coil temperature Tcoil>53℃ for 3 consecutive minutes;

[0110] Outdoor ambient temperature>20℃;

[0111] The W1 and W2 signals sent by the wired controller disappear.

[0112] Exit action: turn off W1 output signal, and the wind speed exits forced high wind. Electric heating entry condition 2: (When the following conditions are met at the same time)

[0113] Heating or automatic heating mode operation;

[0114] Indoor ambient temperature Troom < 22°C;

[0115] The compressor is running;

[0116] The indoor fan is running;

[0117] Indoor coil temperature <43°C;

[0118] There is no fault in the internal unit;

[0119] Receive the W1 signal and W2 signal sent by the wire controller.

[0120] Execute action:

[0121] The indoor fan is forced to operate at high speed;

[0122] The electric heating related relay is energized and the secondary electric heating starts.

[0123] Exit conditions: (Meet any of the following conditions)

[0124] Mode switched to non-heating mode;

[0125] Indoor ambient temperature Troom>25℃;

[0126] The indoor fan stops running;

[0127] The compressor stops running;

[0128] Indoor coil temperature Tcoil>48℃ for 3 consecutive minutes;

[0129] Outdoor ambient temperature>20℃;

[0130] The W1 and W2 input signals sent by the wired remote control disappear.

[0131] Exit action: Turn off the output W2 signal and keep the wind speed at forced high.

[0132] As one of the optional embodiments, the controller is further configured to:

[0133] When the electric heating is turned off, the indoor fan is controlled to exit the strong wind gear and operate at the corresponding wind gear according to the set temperature.

[0134] For details, please refer to Figure 9 , Figure 9 This is a fourth working flow diagram of a controller in an air conditioner provided by an embodiment of the present invention. In this embodiment of the present invention, when the electric heating is turned off, the indoor fan is controlled to exit the high-speed setting and operate in the heating mode according to the normal model, operating at the corresponding setting according to the set temperature.

[0135] See also Figure 10 , Figure 10 The flowchart of a method for preventing cold wind from blowing in an air conditioner provided in one embodiment of the present invention is shown. The method for preventing cold wind from blowing in an air conditioner provided in an embodiment of the present invention is applied to an air conditioner including an indoor heat exchanger, an indoor fan, an outdoor heat exchanger, an outdoor fan, a compressor, a flow regulating valve, a four-way valve, and an electric heating detection circuit. The compressor, the flow regulating valve, the four-way valve, the outdoor heat exchanger, and the indoor heat exchanger are connected by pipes to form a refrigerant circulation loop. The electric heating detection circuit is used to detect whether electric heating is present and includes a first circuit, a second circuit, and a zero-crossing monitoring circuit. The method for preventing cold wind from blowing in an air conditioner includes:

[0136] S1. When the air conditioner is in heating mode, if it is detected that the first circuit is closed and the second circuit is connected to the zero-crossing monitoring circuit, it is determined that electric heating is present, the electric heating is started, and the indoor fan is controlled to operate at a strong wind speed;

[0137] S2. If it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that there is no electric heating and the indoor fan is turned off.

[0138] Specifically, embodiments of the present invention employ an electric heating detection circuit to detect whether the device has electric heating. This circuit includes a first circuit, a second circuit, and a zero-crossing monitoring circuit. If electric heating is present, the first circuit closes, the second circuit connects to the zero-crossing monitoring circuit, and the second circuit can transmit a second signal to the zero-crossing monitoring circuit. If electric heating is absent, the first circuit opens, the second circuit is disconnected from the zero-crossing monitoring circuit, and the second circuit is unable to transmit the second signal to the zero-crossing monitoring circuit. Based on the aforementioned principles, embodiments of the present invention configure the controller so that, when the air conditioner is in heating mode, if the first circuit is closed and the second circuit connects to the zero-crossing monitoring circuit, electric heating is determined to be present. In this case, the anti-cold wind control logic is not required, and the electric heating is directly activated. The indoor fan is then controlled to operate at the high speed setting, i.e., the indoor fan speed is adjusted to the maximum speed and the set temperature is set to the ambient temperature + 4°C. It should be noted that as long as the air conditioner is in heating mode, the electric heating is activated at the high speed setting, regardless of whether defrosting is in progress. If it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that there is no electric heating. At this time, it is necessary to run the common anti-cold wind control logic of existing models, turn off the indoor fan, and run a breeze when it is detected that the indoor coil temperature is between fixed temperatures 1 and 2. When it is detected that the indoor coil temperature reaches above fixed temperature 2, it starts normally and the anti-cold wind ends.

[0139] The embodiment of the present invention determines whether the machine has electric heating by setting an electric heating detection circuit. If electric heating is available, the electric heating is actively turned on and the anti-cold wind control logic is not run. Since the electric heating power optional in North America is often large, the heat from the electric heating can completely cover the cool air blown out during the machine startup phase or defrosting phase, greatly improving the user's continuous heating experience. Regardless of whether the machine is defrosted or not, hot air is always blown indoors.

[0140] As an optional embodiment, the method further includes:

[0141] When it is determined that electric heating is present, if a first signal of the first circuit or a second signal of the second circuit is detected, the first level electric heating is turned on;

[0142] If the first signal of the first circuit and the second signal of the second circuit are detected, the secondary electric heating is turned on.

[0143] Specifically, after determining that the machine is in electric heating mode, the embodiment of the present invention determines the electric heating level based on the first signal (W1) of the first circuit and the second signal (W2) of the second circuit in the electric heating detection circuit. If either the first signal (W1) of the first circuit or the second signal (W2) of the second circuit is detected, the first level of electric heating is activated. That is, as long as either signal (W1) or (W2) is detected, only the first level of electric heating is activated. If both the first signal (W1) of the first circuit and the second signal (W2) of the second circuit are detected, the second level of electric heating is activated. That is, both signals (W1 and W2) must be detected simultaneously for the second level of electric heating to be activated. It is important to note that the condition for exiting the first level of electric heating is the absence of both the W1 and W2 signals, as the presence of either signal activates the first level of electric heating. The condition for exiting the second level of electric heating is: if either the W1 or W2 signal disappears, the first level of electric heating control is activated; if both the W1 and W2 signals disappear, the electric heating is completely deactivated.

[0144] As an optional embodiment, the method further includes:

[0145] When it is determined that electric heating is present, if it is detected that the outdoor ambient temperature is less than a first temperature threshold, the secondary electric heating is forcibly turned on, and the outdoor fan is controlled to stop running.

[0146] Specifically, in this embodiment of the present invention, when electric heating is detected, if the outdoor ambient temperature is detected to be less than a first temperature threshold (for example, less than -20°C), and the unit is in heating mode, the secondary electric heating is forcibly activated, the outdoor fan is stopped, and the indoor fan is operated at a high speed. This is because when the outdoor ambient temperature is too low, the compressor pressure indicator will exceed the compressor specification range, which can cause damage over time. Furthermore, the compressor oil will separate from the refrigerant at very low temperatures.

[0147] As an optional embodiment, the method further includes:

[0148] When it is determined that electric heating is present, if it is detected that the air conditioner satisfies any one of the preset conditions, the electric heating is turned off; wherein the preset conditions are:

[0149] The air conditioner is in non-heating mode;

[0150] The indoor ambient temperature is greater than a second temperature threshold;

[0151] The indoor fan stops running;

[0152] The compressor stops running;

[0153] The indoor coil temperature is greater than a third temperature threshold for a continuous preset time;

[0154] The outdoor ambient temperature is greater than a fourth temperature threshold;

[0155] The first signal of the first loop and the second signal of the second loop are not detected.

[0156] Specifically, in the embodiment of the present invention, when it is determined that electric heating is present, if it is detected that the air conditioner meets any one of the preset conditions, the electric heating is turned off. The preset conditions are:

[0157] The air conditioner is in non-heating mode; because when the air conditioner is in cooling mode, it is necessary to prevent cold wind.

[0158] The indoor ambient temperature is greater than the second temperature threshold; because when the indoor ambient temperature is high, the heating capacity of the machine itself can already meet the user's needs. At this time, if the electric heating is turned on, it will waste electricity resources. Secondly, the air outlet temperature will be very high, resulting in poor user comfort.

[0159] Stop the indoor fan. When the indoor fan stops, it no longer circulates air. If the electric heater is turned on at this time, the heat will not be effectively dissipated, which may cause local overheating and even pose a safety hazard. Also, without the fan circulating the air, the heat generated by the electric heater cannot be evenly distributed throughout the room, thus failing to effectively raise the indoor temperature.

[0160] The compressor stops running; when the compressor stops, the heating cycle also stops, and the system no longer requires additional heating. Secondly, turning on electric heating when the compressor stops can increase energy consumption. This is because electric heating consumes energy to generate heat, and when the compressor is stopped, this heat may not be effectively utilized, resulting in energy waste.

[0161] The indoor coil temperature is greater than the third temperature threshold for a continuous preset time. When the indoor coil temperature is greater than the third temperature threshold for a continuous preset time, it indicates that the heating capacity of the machine itself has already met the user's needs. At this time, if electric heating is turned on again, it will waste electricity resources. Secondly, the air outlet temperature will be very high, resulting in poor user comfort.

[0162] The outdoor ambient temperature is greater than the fourth temperature threshold. This indicates a relatively warm environment, which helps maintain a comfortable indoor temperature. In this case, the temperature difference between indoor and outdoor is small, and heat exchange is relatively smooth, so additional electric heating is not required to raise the indoor temperature. Secondly, electric heating is primarily used to supplement indoor heat, especially when the outdoor temperature is low and the indoor temperature is difficult to maintain. When the outdoor temperature is higher, the indoor temperature can usually be maintained at a comfortable level through natural convection or other heating methods in the system (such as heat generated by compressor operation), eliminating the need for additional electric heating. Furthermore, from an energy utilization perspective, activating electric heating when the outdoor temperature is high results in unnecessary energy waste. Electric heating consumes energy to generate heat, and when the outdoor temperature is high, this heat may not be fully utilized, resulting in low energy efficiency. Finally, frequently activating electric heating may negatively impact system stability and lifespan. When the outdoor temperature is high, the system may already be operating in a relatively stable state. Activating electric heating at this time may disrupt system balance, increase system burden, and even cause failure or damage.

[0163] The first signal of the first circuit and the second signal of the second circuit are not detected; because as long as one signal exists, the first level electric heating will be turned on, and the electric heating will not be turned off until both the first signal and the second signal disappear.

[0164] As an optional embodiment, the method further includes:

[0165] When the electric heating is turned off, the indoor fan is controlled to exit the strong wind gear and operate at the corresponding wind gear according to the set temperature.

[0166] Specifically, in the embodiment of the present invention, when the electric heating is turned off, the indoor fan is controlled to exit the strong wind gear, and the heating mode is operated according to the ordinary model, and the corresponding wind gear is operated according to the set temperature.

[0167] An embodiment of the present invention provides an air conditioner and a cold wind prevention control method thereof. An electric heating detection circuit is provided to determine whether the machine has electric heating. The electric heating detection circuit includes a first circuit, a second circuit, and a zero-crossing monitoring circuit. When the air conditioner is in heating mode, if it is detected that the first circuit is closed and the second circuit is connected to the zero-crossing monitoring circuit, it is determined that electric heating is present, the electric heating is started, and the indoor fan is controlled to operate at a high wind speed. If it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that electric heating is not present and the indoor fan is turned off. In the case of electric heating, the embodiment of the present invention actively turns on the electric heating and does not run the cold wind prevention control logic. Since the electric heating power optional in North America is often large, the heat from the electric heating can completely cover the cold air blown out during the machine startup or defrosting phase, greatly improving the user's continuous heating experience. Regardless of whether the machine is defrosted, hot air is always blown indoors.

[0168] It should be noted that the system embodiment described above is merely illustrative, wherein the units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed across multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment. In addition, in the drawings of the system embodiment provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, which can be specifically implemented as one or more communication buses or signal lines. A person of ordinary skill in the art can understand and implement the present invention without inventive work.

[0169] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. An air conditioner, characterized in that: include: The indoor unit is used to exchange heat with the indoor air and is equipped with an indoor heat exchanger and an indoor fan; The outdoor unit is used to exchange heat with outdoor air, and is equipped with an outdoor heat exchanger, an outdoor fan, a compressor, a flow regulating valve and a four-way valve. The compressor, the flow regulating valve, the four-way valve, the outdoor heat exchanger and the indoor heat exchanger are connected by pipelines to form a refrigerant circulation loop; The electric heating detection circuit is used to detect whether electric heating exists, and includes a first circuit, a second circuit, and a zero-crossing monitoring circuit; The controller is configured such that, when the air conditioner is in heating mode, if it is detected that the first circuit is closed and the second circuit is connected to the zero-crossing monitoring circuit, it is determined that electric heating is present, the electric heating is started, and the indoor fan is controlled to run at a high wind speed; if it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that electric heating is not present and the indoor fan is turned off.

2. The air conditioner according to claim 1, wherein The controller is further configured to: When it is determined that electric heating is present, if a first signal of the first circuit or a second signal of the second circuit is detected, the first level electric heating is turned on; If the first signal of the first circuit and the second signal of the second circuit are detected, the secondary electric heating is turned on.

3. The air conditioner according to claim 2, wherein: The controller is further configured to: When it is determined that electric heating is present, if it is detected that the outdoor ambient temperature is less than a first temperature threshold, the secondary electric heating is forcibly turned on, and the outdoor fan is controlled to stop running.

4. The air conditioner according to claim 3, wherein: The controller is further configured to: When it is determined that electric heating is present, if it is detected that the air conditioner satisfies any one of the preset conditions, the electric heating is turned off; wherein the preset conditions are: The air conditioner is in non-heating mode; The indoor ambient temperature is greater than a second temperature threshold; The indoor fan stops running; The compressor stops running; The indoor coil temperature is greater than a third temperature threshold for a continuous preset time; The outdoor ambient temperature is greater than a fourth temperature threshold; The first signal of the first loop and the second signal of the second loop are not detected.

5. The air conditioner according to claim 4, wherein: The controller is further configured to: When the electric heating is turned off, the indoor fan is controlled to exit the strong wind gear and operate at the corresponding wind gear according to the set temperature.

6. A method for preventing cold wind from entering an air conditioner, characterized in that: The method is applied to an air conditioner including an indoor heat exchanger, an indoor fan, an outdoor heat exchanger, an outdoor fan, a compressor, a flow regulating valve, a four-way valve, and an electric heating detection circuit, wherein the electric heating detection circuit is used to detect whether electric heating exists, and includes a first circuit, a second circuit, and a zero-crossing monitoring circuit. The air conditioner cold wind prevention control method includes: When the air conditioner is in heating mode, if it is detected that the first circuit is closed and the second circuit is connected to the zero-crossing monitoring circuit, it is determined that electric heating is present, the electric heating is started, and the indoor fan is controlled to operate at a strong wind speed; If it is detected that the first circuit is disconnected and the second circuit is not connected to the zero-crossing monitoring circuit, it is determined that there is no electric heating and the indoor fan is turned off.

7. The air conditioner cold wind prevention control method according to claim 6, characterized in that: The method further comprises: When it is determined that electric heating is present, if a first signal of the first circuit or a second signal of the second circuit is detected, the first level electric heating is turned on; If the first signal of the first circuit and the second signal of the second circuit are detected, the secondary electric heating is turned on.

8. The cold wind prevention control method for an air conditioner according to claim 7, wherein: The method further comprises: When it is determined that electric heating is present, if it is detected that the outdoor ambient temperature is less than a first temperature threshold, the secondary electric heating is forcibly turned on, and the outdoor fan is controlled to stop running.

9. The cold wind prevention control method for an air conditioner according to claim 8, wherein: The method further comprises: When it is determined that electric heating is present, if it is detected that the air conditioner satisfies any one of the preset conditions, the electric heating is turned off; wherein the preset conditions are: The air conditioner is in non-heating mode; The indoor ambient temperature is greater than a second temperature threshold; The indoor fan stops running; The compressor stops running; The indoor coil temperature is greater than a third temperature threshold for a continuous preset time; The outdoor ambient temperature is greater than a fourth temperature threshold; The first signal of the first loop and the second signal of the second loop are not detected.

10. The cold wind prevention control method for an air conditioner according to claim 9, wherein: The method further comprises: When the electric heating is turned off, the indoor fan is controlled to exit the strong wind gear and operate at the corresponding wind gear according to the set temperature.

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