JP2012122679A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner that accurately detects a failure in a refrigerating cycle to reliably protect a compressor even when a room temperature is low.SOLUTION: The air conditioner stops operation of the compressor 2 when a temperature difference between an indoor heat exchanger 15 and a room temperature is within a predetermined temperature range after the lapse of a predetermined time since the start of the operation of the compressor 2, detects changes in temperature of an outdoor heat exchanger 3 when the temperature difference between the indoor heat exchanger 15 and the room temperature is larger than a predetermined temperature while an indoor blow fan 14 is stopped, and when the change in temperature of the outdoor heat exchanger 3 is within a predetermined range, stops operation of the compressor 2.

Description

  The present invention relates to control of an air conditioner.

  In a conventional air conditioner control method, after a predetermined time has elapsed since the operation of the compressor was started, the room temperature and the temperature in the middle of the indoor heat exchanger were detected, and the detected room temperature and the indoor heat exchanger were detected. There is protection control that determines that the refrigerant is not flowing when the temperature difference from the temperature is within a predetermined temperature, and stops the compressor (see, for example, Patent Document 1).

JP 2003-090582 A

  However, in the protection control of the conventional air conditioner, for example, when forgetting to open the valve at the time of installation, the indoor blower fan is stopped to prevent cold air, and the temperature of the indoor heat exchanger is kept low. Even though the refrigerant is not flowing, there is a problem that a temperature difference occurs between the room temperature and the temperature of the indoor heat exchanger, and it is erroneously determined that the refrigerant is flowing.

  This is because there is a problem on some refrigeration cycle, and the refrigerant discharged from the compressor flows to the indoor unit but does not flow to the outdoor unit. This is because exhaust heat is not performed and a difference occurs between the room temperature and the temperature of the indoor heat exchanger.

  The present invention solves the above-mentioned conventional problems, and provides an air conditioner that can accurately detect a malfunction of a refrigeration cycle and reliably protect a compressor even when the room temperature is low. With the goal.

  In order to solve the conventional problems, an air conditioner according to the present invention includes at least a compressor, an indoor heat exchanger, an electronic expansion valve, an outdoor heat exchanger, and an indoor air blown to the indoor heat exchanger. An outdoor fan for blowing air to the outdoor heat exchanger, an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, and an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger; And a room temperature detection means for detecting the room temperature, and when a predetermined time has elapsed since the start of the compressor operation, the compressor operation is stopped when the temperature difference between the indoor heat exchanger and the room temperature is within the predetermined temperature. When the temperature difference between the indoor heat exchanger and room temperature is equal to or higher than a predetermined temperature and the indoor fan is stopped, the temperature change of the outdoor heat exchanger is detected and the temperature of the outdoor heat exchanger is detected. If the change is within the prescribed range, stop the compressor operation. Ri, surely detect a defect such as open forgetting to two-way valve and three-way valve which connects the indoor unit and the outdoor unit, can be protected compressor.

Moreover, in order to solve the said conventional subject, the air conditioner of this invention ventilates to a compressor, an indoor heat exchanger, an electronic expansion valve, an outdoor heat exchanger, and an indoor heat exchanger at least. An indoor fan, an outdoor fan that blows air to the outdoor heat exchanger, an indoor heat exchanger temperature detection means that detects the temperature of the indoor heat exchanger, and an outdoor heat exchanger temperature detection that detects the temperature of the outdoor heat exchanger Means, a room temperature detecting means for detecting the room temperature, and an outdoor temperature detecting means for detecting the outdoor temperature, and a temperature difference between the indoor heat exchanger and the room temperature when a predetermined time elapses after the operation of the compressor is started. When the air temperature is within the predetermined temperature, the operation of the compressor is stopped, and when the temperature difference between the indoor heat exchanger and the room temperature is equal to or higher than the predetermined temperature and the indoor fan is stopped, the outdoor heat exchanger The temperature difference between and the outdoor air temperature If it is within, by stopping the operation of the compressor, it is possible to reliably detect problems such as forgetting to open the two-way valve and three-way valve connecting the indoor unit and outdoor unit, and to protect the compressor it can.

  The present invention can provide an air conditioner that can accurately detect a refrigeration cycle defect and reliably protect a compressor even when the room temperature is low.

The block diagram of the air conditioner in Embodiment 1 of this invention Flowchart of protection control of the compressor of the air conditioner in the first embodiment Flowchart of protection control of compressor of air conditioner in Embodiment 2 of the present invention

  An air conditioner according to a first aspect of the present invention includes at least a compressor, an indoor heat exchanger, an electronic expansion valve, an outdoor heat exchanger, an indoor fan for blowing air to the indoor heat exchanger, and an outdoor heat exchanger. An outdoor fan for blowing air, an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger, and a room temperature detecting means for detecting the room temperature And the compressor operation is stopped when the temperature difference between the indoor heat exchanger and the room temperature is within a predetermined temperature when a predetermined time has elapsed after the compressor starts operating, and the indoor heat exchanger and the room temperature are stopped. When the temperature difference between and the indoor fan is stopped, the temperature change of the outdoor heat exchanger is detected, and if the temperature change of the outdoor heat exchanger is within a predetermined range, Connecting the indoor unit to the outdoor unit by stopping the compressor operation Reliably detect problems such as open forget the two-way valve and three-way valve that, it is possible to achieve the protection of the compressor.

  The air conditioner of the second invention is at least a compressor, an indoor heat exchanger, an electronic expansion valve, an outdoor heat exchanger, an indoor fan for blowing air to the indoor heat exchanger, and an outdoor heat exchanger. An outdoor fan for blowing air, an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger, and a room temperature detecting means for detecting the room temperature And an outdoor air temperature detecting means for detecting the outdoor air temperature, and when a predetermined time has elapsed after starting the operation of the compressor, when the temperature difference between the indoor heat exchanger and the room temperature is within a predetermined temperature, When the operation is stopped and the temperature difference between the indoor heat exchanger and the room temperature is equal to or higher than a predetermined temperature and the indoor fan is stopped, the temperature of the outdoor heat exchanger is compared with the outdoor air temperature, If the temperature difference is within the specified temperature, stop the compressor operation. It allows problems such as open forgetting to two-way valve and three-way valve which connects the indoor unit and an outdoor unit by reliably detected, it is possible to protect the compressor.

  In the air conditioner of the third invention, particularly in the first or second invention, when the indoor blower fan is stopped when a predetermined time has elapsed since the operation of the compressor was started, By stopping the outdoor blower fan or making it a breeze, the temperature change of the outdoor heat exchanger is surely generated, and the detection accuracy can be improved.

  In the air conditioner of the fourth invention, particularly in the first to third inventions, an initial failure such as forgetting to open the two-way or three-way valve or clogging of the expansion valve can be determined by performing only when the compressor is started for the first time. Since the initial operation is not performed after the first installation and normal operation is continued, the determination operation different from the normal air-conditioning operation such as stopping the outdoor blower fan is not performed, thereby impairing the comfort. Can be prevented.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of an air conditioner according to Embodiment 1 of the present invention. As shown in FIG. 1, the air conditioner of the present invention is configured by connecting an outdoor unit 1 installed outdoors and an indoor unit 13 installed indoors by a refrigerant pipe 5 and a refrigerant pipe 6.

  Next, the configuration of the outdoor unit 1 will be described. The outdoor unit 1 in the first embodiment includes a compressor 2 that compresses a refrigerant, a four-way valve 7 that switches a refrigerant flow path, and an outdoor heat exchanger 3 that exchanges heat between the outside air and the refrigerant. The electronic expansion valve 8 for reducing the pressure of the refrigerant and the outdoor fan 4 for blowing heat to the outdoor heat exchanger 3 and promoting heat exchange between the refrigerant and the air are provided.

  Furthermore, an outdoor heat exchanger temperature detecting means 9 for detecting the temperature of the outdoor heat exchanger 3, an outdoor air temperature detecting means 10 for detecting the outdoor air temperature, and a discharge temperature for detecting the discharge refrigerant temperature on the discharge side of the compressor 2. The detection means 20 is provided, and each is comprised by the apparatus which can detect temperature, such as a thermistor.

  Next, the configuration of the indoor unit 13 will be described. The indoor unit 13 according to the first embodiment has an internal heat exchanger 15 for exchanging heat between the indoor air and the refrigerant, and an indoor heat exchanger 15 for exchanging heat between the refrigerant and the indoor air. And at least an indoor fan 14 to be promoted.

  Further, the apparatus includes an indoor heat exchanger temperature detecting means 16 for detecting the temperature of the indoor heat exchanger 15 and a room temperature detecting means 17 for detecting the room temperature, each of which is a device capable of detecting the temperature of a thermistor or the like.

  In addition, as shown in FIG. 1, a dotted line arrow shows the flow direction of the refrigerant | coolant at the time of air_conditionaing | cooling operation, and a solid line arrow shows the flow direction of the refrigerant | coolant at the time of heating operation. Similarly, the dotted line of the four-way valve 7 indicates the refrigerant flow path during the cooling operation, and the solid line arrow indicates the refrigerant flow path during the heating operation.

  In addition, a two-way valve 11 and a three-way valve 12 for attaching refrigerant pipes 5 and 6 connected to the indoor unit 13 are provided at a pipe attachment port provided on the side surface of the outdoor unit 1. Usually, an air conditioner installer needs to open the two-way valve 11 and the three-way valve 12 after connecting the refrigerant pipes 5 and 6 when the air conditioner is installed.

  However, there are cases where the two-way valve 11 and the three-way valve 12 are forgotten to be opened and the air conditioning operation cannot be normally performed. Therefore, in this embodiment, it is reliably detected that some abnormality has occurred on the refrigeration cycle, and the compressor is stopped to protect the compressor. Hereinafter, protection control of the compressor in the first embodiment will be described.

  FIG. 2 is a flowchart of compressor protection control according to Embodiment 1 of the present invention. First, operation is started in step SP01. In step SP02, it is determined whether the temperature detected by the discharge temperature detecting means 20 is lower than a predetermined temperature To (for example, 100 ° C.). The predetermined temperature at this time is a high temperature upper limit temperature that needs to protect the compressor, and is not uniquely determined by the performance of the compressor.

If the temperature detected by the discharge temperature detecting means 20 in step SP02 is higher than the predetermined temperature To, the compressor 2 is stopped in step SP03. If the temperature detected by the discharge temperature detecting means 20 in step SP02 is lower than the predetermined temperature To, the process proceeds to step SP04.

  In step SP04, it is determined whether or not a predetermined time Ls has elapsed after the operation of the compressor 2 is started. The predetermined time Ls at this time sets a time for the refrigerant to stabilize, and varies depending on the configuration of the air conditioner. In the case of the air conditioner in the present embodiment, an experimentally calculated time is set. Yes. For example, in the case of this embodiment, it is 5 minutes in the cooling operation, and 15 minutes in the heating operation.

  Then, it is determined whether or not the predetermined time Ls has elapsed since the start of the operation of the compressor 2 in step SP04. If the predetermined time Ls has not elapsed, the process returns to step SP02, and the predetermined time Ls has elapsed. If so, the process proceeds to step SP05.

  In step SP05, the room temperature detected by the room temperature detection means 17 is compared with the indoor heat exchanger temperature detected by the indoor heat exchanger temperature detection means 16, and the temperature difference is calculated. And it is judged whether a temperature difference is lower than predetermined temperature Ts (for example, 4 degreeC). The predetermined temperature Ts at this time varies depending on the configuration of the system and is calculated experimentally and is a preset temperature, and is not uniquely determined. In this embodiment, the temperature is set to 4 ° C.

  In step SP05, it is determined whether or not the absolute value of the temperature difference between the temperature of the indoor heat exchanger and the room temperature is within a predetermined temperature Ts. If the absolute value of the temperature difference is within the predetermined temperature Ts in step SP05, the process proceeds to step SP06, where it is determined that no refrigerant is flowing, and the operation of the compressor 2 is stopped. Even when the temperature difference is detected to be equal to or higher than the predetermined temperature Ts, the indoor air blowing fan may not be generated because the indoor air blowing fan is not driven. Therefore, in step SP07, the indoor air blowing fan 14 is detected. Judging whether is driving.

  If the indoor fan 14 is being driven in step SP07, the process proceeds to step SP08 and is determined to be normal operation. However, if the indoor fan 14 is not driven in step SP07, the process proceeds to step SP09, and the outdoor heat exchanger temperature detected by the outdoor heat exchanger temperature detecting means 9 is stored.

  Next, in step SP10, the outdoor blower fan 4 is stopped or made a breeze and the process proceeds to the next step. As a result, the temperature change in the outdoor heat exchanger 3 is applied, so that the temperature change can be reliably detected if it is normal.

  In step SP11, the difference between the temperature detected by the outdoor heat exchanger temperature detecting means 9 and the temperature of the outdoor heat exchanger stored in step SP09 is compared, and the change is equal to or higher than a predetermined temperature Tg (for example, 4 ° C.). Judge whether there was. The predetermined temperature Tg at this time differs depending on the system configuration and is calculated experimentally, is a preset temperature, and is not uniquely determined. In this embodiment, the temperature is set to 4 ° C.

  If the temperature change of the outdoor heat exchanger temperature is greater than or equal to the predetermined temperature Tg in step SP11, the process proceeds to step SP13, where normal operation is performed, but the change is within the predetermined temperature Tg. The process proceeds to step SP12.

  In step SP12, it is determined whether or not a predetermined time Lg has elapsed since the outdoor blower fan 4 was stopped or operated in a light wind in step SP10. As the predetermined time Lg at this time, an experimentally calculated time is set in advance, and is set to 4 minutes in the present embodiment.

  In step SP12, if the predetermined time Lg has not elapsed, the process returns to step SP11. If the predetermined time Lg has elapsed, the process proceeds to step SP14, where the compressor 2 is stopped and is not restarted. In addition, when stopping the compressor 2 in step SP03, step SP06, and step SP14, an indicator or the like may be provided in the outdoor unit 1 or the indoor unit 13 to display an error code or the like. In that case, recognition to a service person or the like can be promoted, and serviceability can be improved.

  In addition, by performing this control only when the compressor 2 is started for the first time, it is possible to determine initial failure such as forgetting to open the two-way valve 11 or the three-way valve 12 or clogging of the expansion valve. Since the normal operation is continued without performing the determination, it is possible to prevent the comfort from being impaired by not performing the determination operation different from the normal air conditioning operation such as stopping the outdoor blower fan 4.

  As described above, in the present embodiment, it is possible to accurately determine whether or not there is an abnormality in the refrigeration cycle when the air conditioner is installed.

(Embodiment 2)
Since the air conditioner in this Embodiment 2 is the same structure as Embodiment 1, the same code | symbol as Embodiment 1 is attached | subjected and the description is abbreviate | omitted.

  FIG. 3 is a flowchart of protection control of the compressor of the air conditioner according to the second embodiment. The difference from FIG. 2 is that the temperature change of the outdoor heat exchanger 3 is detected in step SP11 of FIG. 2, but in this embodiment, in step 21, the temperature of the outdoor heat exchanger 3 and the outside air temperature detecting means are detected. 10 is compared with the temperature difference with the outside air temperature detected. Since the other steps are the same as those in the first embodiment, the same step numbers are assigned and description thereof is omitted.

  In step SP21, the temperature of the outdoor heat exchanger 3 is compared with the outside air temperature, and it is determined whether the absolute value of the temperature difference is within a predetermined temperature Tk (for example, 4 ° C.). The predetermined temperature Tk at this time differs depending on the system configuration and is calculated experimentally, is a preset temperature, and is not uniquely determined. In this embodiment, the temperature is set to 4 ° C.

  If the absolute value of the temperature difference is greater than or equal to the predetermined temperature Tk in step SP21, the process proceeds to step SP13 and normal operation is performed. If it is within the predetermined temperature Tk at step SP21, the process proceeds to step SP12. The subsequent steps are the same as those in the first embodiment.

  As described above, in the present embodiment, it is possible to accurately determine whether or not there is an abnormality in the refrigeration cycle when the air conditioner is installed. As in the first embodiment, this control is performed only when the compressor 2 is activated for the first time, thereby determining initial failure such as forgetting to open the two-way valve 11 or the three-way valve 12 or clogging of the expansion valve. In order to continue normal operation without making a determination after the first installation, it is possible to impair comfort by not performing a determination operation different from normal air-conditioning operation such as stopping the outdoor fan 4 Can be prevented.

  The air conditioner according to the present invention can be applied to a multi-room air conditioner.

DESCRIPTION OF SYMBOLS 1 Outdoor unit 2 Compressor 3 Outdoor heat exchanger 4 Outdoor ventilation fan 7 Four-way valve 8 Electronic expansion valve 9 Outdoor heat exchanger temperature detection means 10 Outside air temperature detection means 11 Two-way valve 12 Three-way valve 13 Indoor unit 14 Indoor ventilation fan 15 Indoor heat exchanger 16 Indoor heat exchanger temperature detection means 17 Room temperature detection means

Claims (4)

At least a compressor, an indoor heat exchanger, an electronic expansion valve, an outdoor heat exchanger, an indoor fan for blowing air to the indoor heat exchanger, an outdoor fan for blowing air to the outdoor heat exchanger, The compressor comprising: an indoor heat exchanger temperature detecting means for detecting a temperature of the heat exchanger; an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger; and a room temperature detecting means for detecting a room temperature. When the temperature difference between the indoor heat exchanger and the room temperature is within a predetermined temperature when a predetermined time has elapsed since the start of the operation, the operation of the compressor is stopped, and the temperature between the indoor heat exchanger and the room temperature When the difference is equal to or higher than a predetermined temperature and the indoor fan is stopped, the temperature change of the outdoor heat exchanger is detected, and if the temperature change of the outdoor heat exchanger is within a predetermined range, The operation of the compressor is stopped. Air-conditioner. At least a compressor, an indoor heat exchanger, an electronic expansion valve, an outdoor heat exchanger, an indoor fan for blowing air to the indoor heat exchanger, an outdoor fan for blowing air to the outdoor heat exchanger, An indoor heat exchanger temperature detecting means for detecting the temperature of the heat exchanger, an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger, a room temperature detecting means for detecting the room temperature, and an outdoor air temperature are detected. An outside air temperature detecting means, and when a predetermined time has elapsed after starting the operation of the compressor, the operation of the compressor is stopped when a temperature difference between the indoor heat exchanger and room temperature is within a predetermined temperature. When the temperature difference between the indoor heat exchanger and room temperature is equal to or higher than a predetermined temperature and the indoor fan is stopped, the temperature of the outdoor heat exchanger is compared with the outdoor air temperature, and If the temperature difference is within a predetermined temperature, the compressor An air conditioner characterized by stopping the operation. The said outdoor ventilation fan is stopped or made into a breeze, when the said indoor ventilation fan has stopped when predetermined time passes since the driving | operation of the said compressor is started, The 1st or 2 is characterized by the above-mentioned. The air conditioner described. The air conditioner which performs control of any one of Claim 1 to 3 only at the time of the first time starting of the said compressor.