JP4711438B2 - Refrigeration air conditioner and refrigeration air conditioning method - Google Patents

Description

  The present invention relates to a refrigeration air-conditioning apparatus and a refrigeration air-conditioning method, and more particularly to a structure and operation method of a use-side refrigeration air-conditioning apparatus equipped with a drain pump that discharges drain water.

  A conventional refrigeration air conditioner equipped with a conventional drain pump includes a drain pump for discharging drain water, a temperature detection means for detecting room temperature, a humidity detection means for detecting humidity, and a microcomputer for controlling the air conditioning operation. In cooling operation, room temperature and humidity are read at regular intervals, a setting area pre-assigned to the storage unit in the microcomputer as parameters of temperature and humidity is determined, and the operation time of the drain pump corresponding to the setting area And stop time.

  A setting area pre-allocated with temperature and humidity as parameters is provided in the storage unit in the microcomputer, and is divided into four areas A, B, C, and D from a high temperature / high humidity area A to a low temperature / low humidity area D. . It is determined which of the above four areas the detected room temperature and humidity are in, and the drain pump is operated in accordance with the drain pump operation mode determined for each area (see, for example, Patent Document 1).

JP-A-4-158150 (page 2, lower right column, line 3 to page 3, upper left column, line 5, FIG. 1, FIG. 3)

  In the conventional technique, the operation method of the drain pump is determined from the temperature and humidity of the room air, but there is a problem that the amount of dehumidification generated from the heat exchanger cannot be estimated only by the temperature and humidity of the room air. For example, during cooling operation, if the ambient air temperature and humidity detected by the user-side refrigeration air conditioner are in the high-temperature / high-humidity range A, but the refrigerant temperature of the heat exchanger is equal to or higher than the dew point temperature of the room air, the user side Since the air passing through the refrigeration air conditioner is not dehumidified, no drain is generated. As a result, the drain pump is wastefully operated.

  On the other hand, during cooling operation, even if the ambient air temperature and humidity detected by the user-side refrigeration air conditioner are in the low-temperature / low-humidity range D, the refrigerant temperature of the heat exchanger is considerably low and the air volume is very large In this case, the air passing through the use side refrigeration air conditioner is dehumidified and drainage is generated. Since the amount is not small, there is a possibility that drain water overflows the drain tray due to insufficient operation time of the drain pump.

  The present invention has been made to solve these problems, and provides a refrigerating and air-conditioning apparatus that avoids wasteful operation of a drain pump and reliably removes necessary drain water during cooling operation. It is aimed.

The refrigerating and air-conditioning apparatus according to the present invention includes a compressor, a heat source side heat exchanger, a decompression unit, a use side heat exchanger, and a heat source side control unit that is controlled in accordance with the operating frequency of the compressor by being connected annularly by a pipe. When the drain water pan for reserving drain water from the utilization-side heat exchanger, a drain pump for discharging the drain water of the drain water pan to the outside, the usage-side control unit having a communication means for connecting the heat source side control unit When the indoor temperature detection means for detecting the room temperature, comprising a refrigerant temperature detecting means for detecting the refrigerant temperature of the utilization for heat exchanger, a cooling operation, the heat source side control unit, the operating frequency of the compressor Sent to the use side control means via the communication means, and the use side control means is based on the operating frequency of the compressor received from the heat source side control means every predetermined time and the refrigerant temperature of the use side heat exchanger during cooling operation. Use side heat exchange And calculating a first enthalpy indicating an enthalpy of the blown air state based on the refrigerant temperature of the use side heat exchanger detected by the refrigerant temperature detecting means, and calculating the calculated first enthalpy. A second enthalpy indicating the enthalpy of the intake air is calculated based on the enthalpy and the calculated cooling capacity of the use side heat exchanger. Next, while changing the indoor humidity, the indoor humidity and the indoor temperature detecting means The third enthalpy is calculated from the detected room temperature, the calculated third enthalpy is compared with the second enthalpy, the indoor humidity when the two become equal is estimated as the indoor humidity, and then calculating the room dew point temperature from the room humidity was estimated detected room temperature by the temperature detecting means, then the indoor dew point temperature and the calculated detected by the coolant temperature detecting means utilizing The operation time and stop time of the drain pump are determined based on the temperature difference from the refrigerant temperature of the heat exchanger, and then the drain pump is controlled based on the determined operation time and stop time. .

  According to this invention, the refrigerating and air-conditioning apparatus can avoid the wasteful operation of the drain pump during the cooling operation and can reliably remove the necessary drain water.

Embodiment 1 FIG.
FIG. 1 is a refrigerant circuit diagram according to Embodiment 1 of the present invention. The refrigerant circuit includes a heat source side refrigeration apparatus X and a use side refrigeration apparatus Y, and the heat source side refrigeration apparatus X and the use side refrigeration apparatus Y are connected via a gas extension pipe 7 and a liquid extension pipe 8. The heat source side refrigeration apparatus X includes a compressor 1, a four-way valve 2, a heat source side heat exchanger 3, a decompression unit 4, a low pressure liquid reservoir 6, a heat source side blower fan 9, a heat source side blower fan motor 10, and a heat source side control unit 13. Consists of The use side refrigeration air conditioner Y includes a use side heat exchanger 5, a use side blower fan 11, a use side blower fan motor 12, and a use side control means 14.
The indoor temperature detection means 21, the indoor humidity detection means 22, and the refrigerant temperature detection means 23 of the use side heat exchanger are connected to the control means 14 via a wired or wireless communication means indicated by a dotted line. The temperature, pressure detection means, remote controller and communication means mounted on the heat source side heat exchanger are not described because they are not related to the present invention.

FIG. 2 is a cross-sectional view of the use-side refrigeration air conditioner Y according to Embodiment 1 of the present invention. Here, a four-way ceiling cassette type indoor unit is taken as an example. 2, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and the description thereof will be omitted. Here, a drain pump 24, a drain water receiving tray 25, and a drain water discharge pipe 26 are added.
The indoor temperature detection means 21 and the indoor humidity detection means 22 are installed at a position in contact with the intake air of the use side refrigeration air conditioner Y. In addition, the refrigerant temperature detection means 23 of the use side heat exchanger 5 is installed at a position in contact with the piping portion of the use side heat exchanger 5.

  Next, the refrigerant | coolant operation | movement at the time of air_conditionaing | cooling operation is demonstrated using FIG. The high-pressure and high-temperature gas refrigerant discharged from the compressor 1 flows into the heat source side heat exchanger 3 through the four-way valve 2, where it is condensed by exchanging heat with the surrounding air and flows out as high-pressure liquid refrigerant. The high-pressure liquid refrigerant that has flowed out is decompressed by the decompression means 4 to become a low-pressure gas-liquid two-phase refrigerant, and flows into the use-side heat exchanger 5 through the liquid extension pipe 8. Here, the refrigerant exchanges heat with ambient air, evaporates, and flows out as a low-pressure gas refrigerant. The low-pressure gas refrigerant that has flowed out returns to the compressor 1 via the gas extension pipe 7, the four-way valve 2, and the low-pressure liquid reservoir 6.

The refrigerant operation and air operation during the cooling operation will be described with reference to FIG. During the cooling operation, the use side heat exchanger 5 acts as an evaporator, so that a refrigerant having a temperature lower than that of the surrounding air flows in the pipe of the use side heat exchanger, and as a result, the use side heat exchange including the fin portion is performed. The vessel 5 is cooler than the ambient air.
The air sucked from the central portion of the lower end of FIG. 2 by the use side blower fan 11 comes into contact with the use side heat exchanger 5 and is cooled. When the temperature of the use side heat exchanger 5 is lower than the dew point temperature of the intake air, a part of the water vapor contained in the intake air is condensed on the surface of the use side heat exchanger in the process of being cooled and becomes liquid (drain). Become. The cooled air is discharged to the outside from the air outlet.

Next, a method for calculating the dehumidification amount during the cooling operation will be described. FIG. 3 is an air diagram. A shows an intake air state, B shows a saturated humid air state of the use side heat exchanger 5, and C shows a blown air state. The dehumidification amount L [kg / h] can be obtained from the difference between the absolute humidity X1 and Xo [kg / kg '] between the intake air and the blown air and the blown air amount G [kg / h] by the following formula 1.
L [kg / h] = (X1-Xo) * G (1)

The absolute humidity Xo [kg / kg '] of the blown air is obtained by the following procedure. First, the enthalpy i0 [kJ / kg] of the blown air according to the following equation 2 from the enthalpy i1 [kJ / kg] of the intake air, the cooling capacity Q [W] of the use side heat exchanger 5 and the air flow rate G [kg / h]. Can be requested.
io = i1-Q / G * 3.6 (2)
Next, on the air diagram of FIG. 3, the line connecting the line of enthalpy i0 [kJ / kg] of the blown air with the intake air state A and the saturated humid air state B of the use side heat exchanger 5 (AB) ) To obtain the absolute humidity Xo of the blown air.

  When the absolute humidity Xo of the blown air and the absolute humidity Xs of the saturated humid air of the use side heat exchanger 5 are larger than the absolute humidity X1 of the intake air, mass transfer from water vapor to water occurs on the surface of the use side heat exchanger 5 Without dehumidification. Accordingly, the blown air of the use side refrigeration air conditioner is blown out with a sensible heat change (decreased by temperature). To estimate whether drain water is generated by dehumidification and how much it is generated, it is necessary to obtain absolute humidity.

  Next, it will be described below that the presence / absence of drain water and the amount of drain water generated can be estimated using the dew point temperature of the intake air and the saturated humid air temperature of the use side heat exchanger 5 in addition to the absolute humidity. To do.

  The dry-bulb temperature of the intake air A is 27 ° C., the wet-bulb temperature is 19 ° C., the dry-bulb temperature of the blown air C is 13 ° C., the wet-bulb temperature is 12 ° C., and the refrigerant evaporation temperature D of the use side heat exchanger 5 is Set to 10 ° C. Each absolute humidity and dew point temperature are shown in Table 1. From Table 1, the ratio (ac) / (a) of the difference (ac) between the intake air a and the blown air c (ab) and the difference (ad) between the intake air a and the refrigerant temperature d at the absolute humidity and dew point temperature. Since -d) does not change much, the presence / absence of drain water and the generation amount can be estimated even if the dew point temperature of the intake air and the saturated humid air temperature of the use side heat exchanger 5 are used instead of absolute humidity.

As mentioned above, if the absolute humidity and the dew point temperature are calculated from these values by detecting the intake air state, the air flow rate, the saturated humid air state of the use side heat exchanger 5 and the cooling capacity of the use side heat exchanger 5, It was shown that the air condition and dehumidification amount can be obtained uniquely.
Actually, the temperature and humidity of the intake air, the air flow rate, the refrigerant temperature of the use side heat exchanger 5 and the cooling capacity may be detected.

  In the above case, since there are too many detected data items, the following assumptions are made. The air flow rate should be the maximum specified for the product and should not be detected during operation. Necessary for obtaining the air condition, assuming that the heat exchange efficiency based on the enthalpy difference of the use side heat exchanger is 100%, and the blown air condition is the same as the saturated air condition of the refrigerant temperature of the use side heat exchanger. To avoid detecting the cooling capacity during operation. As a result, it is assumed that the data detected during operation is the temperature and humidity of the intake air and the refrigerant temperature of the use side heat exchanger 5. The following description is continued on the assumption that these three data are detected.

FIG. 4 shows a procedure for determining the operation pattern of the drain pump 24. After starting the cooling operation (step S41), in the usage-side refrigeration air-conditioning apparatus Y, the indoor temperature detection means 21, the indoor humidity detection means 22, the refrigerant temperature detection means 23 of the usage-side heat exchanger 5, Is used to detect the indoor temperature Tindb, the indoor humidity Tinwb, and the refrigerant temperature Tr, and the temperature and humidity data are transferred to the use side control means 14 (step S42). Next, the use side control means 14 calculates the room dew point temperature Tro using the room temperature Tindb and the room humidity Tinwb (step S43). The indoor dew point temperature Tro can be uniquely determined from the air diagram of FIG. As an example, FIG. 5 shows a method and formula for obtaining the dew point temperature after obtaining the water vapor saturated vapor pressure Psat and the absolute humidity X. Actually, the calculation is not performed using these equations every time. The calculation result is converted into a data map and stored in the control means 14, and the stored data map is used when necessary.
Therefore, the detailed description of FIG. 5 is omitted.

  Next, the use side control means 14 obtains a value (hereinafter referred to as a temperature difference) ΔT obtained by subtracting the refrigerant temperature Tr from the dew point temperature Tro calculated by the above method (step S44). Based on the temperature difference ΔT, an operation pattern combining the operation time and stop time of the drain pump is determined (step S45). FIG. 6 shows an example of the temperature difference ΔT and the drain pump operation pattern. For example, in the No. 4 region, it is determined that the operation pattern of the drain pump 24 is a 3-minute operation and a 3-minute stop.

  The use side control means 14 operates / stops the drain pump 24 by operating a relay incorporated in the electric circuit of the drain pump 24 (step S46).

  In this description, the dew point temperature is used, but it goes without saying that the absolute humidity of the intake air and the absolute humidity of the saturated air at the refrigerant temperature may be used.

  In this description, the indoor unit is assumed to be a four-way ceiling cassette type indoor unit. However, it goes without saying that the same operation and control can be performed with indoor units having other structures such as a ceiling-mounted type and a wall-mounted type.

  Further, the refrigerant temperature detection means 23 of the use side heat exchanger 5 is installed in contact with the pipe in the vicinity of the center of the pipe path constituting the heat exchanger 5. In order to improve the reliability, it is effective to install the refrigerant temperature detecting means 23 of the use side heat exchanger 5 at two locations near the inlet and the center of the cooling path of the pipe path constituting the heat exchanger 5. . In this case, the lower temperature detected during the cooling operation is regarded as the refrigerant temperature.

  As described above, according to the first embodiment, the compressor, the heat source side heat exchanger, the pressure reducing means, and the use side heat exchanger are sequentially connected in a ring shape by the piping, and the drain water from the use side heat exchanger is stored. A drain water tray, a drain pump for discharging the drain water of the drain water tray to the outside, a use side control means, an indoor temperature detection means for detecting indoor temperature, an indoor humidity detection means for detecting indoor humidity, Refrigerant temperature detection means for detecting the refrigerant temperature of the use side heat exchanger, and the use side control means includes storage means for storing a table in which the temperature difference, the operation time and the stop time of the drain pump are associated with each other. In the cooling operation, the indoor dew point temperature is calculated from the room temperature detected by the room temperature detecting means every predetermined time and the room humidity detected by the room humidity detecting means, and then the calculated room dew point temperature, The operation time and stop time of the drain pump are determined based on the temperature difference between the refrigerant temperature of the use side heat exchanger detected by the medium temperature detection means and the table of the storage means, and then the determined operation time and stop time are determined. By controlling the drain pump based on this, it is possible to avoid unnecessary operation of the drain pump and to reliably remove the necessary drain water.

Embodiment 2. FIG.
Hereinafter, Embodiment 2 of the refrigerating and air-conditioning apparatus according to the present invention will be described. FIG. 7 is a refrigerant circuit diagram, and FIG. 8 is a cross-sectional view of the use-side refrigeration air conditioner. The difference from the first embodiment is that the indoor-side humidity detecting means 22 is not mounted in the use-side refrigeration air-conditioning apparatus Y. Since the refrigerant operation in the cooling operation is the same as that in the previous embodiment, the description thereof is omitted.

  The following assumptions are made as in the first embodiment. The air flow rate should be the maximum specified for the product and should not be detected during operation. In order to obtain the blown air state, assuming that the heat exchange efficiency based on the enthalpy difference of the use side heat exchanger 5 is 100% and the blown air state is the same as the saturated air state of the refrigerant temperature of the use side heat exchanger. Do not detect the required cooling capacity during operation. As a result, two data are detected during operation: the temperature of the intake air and the refrigerant temperature of the use side heat exchanger 5.

  The feature of this embodiment is that the indoor humidity is detected by using the compressor operating frequency F and the refrigerant temperature Tr detected from the refrigerant temperature detecting means 23 of the use side heat exchanger 5 without using the indoor humidity detecting means 22. To guess. FIG. 9 shows a specific procedure for estimating the indoor humidity from the compressor operating frequency F and the refrigerant temperature Tr.

First, the use side control means 14 calculates the compressor refrigerant flow rate Gr [kg / h] (step S91). The refrigerant flow rate can be obtained by the following Equation 3. Where F is the operating frequency of the compressor 1, Vst is the compression chamber volume, and ρs is the compressor suction refrigerant density.
Gr [kg / h] = F [Hz] × 3600 × Vst [m3] × ρs [kg / m3] (3)
The operating frequency F of the compressor 1 is controlled by the heat source side control means 13 every predetermined time, and the control value is used. Since Vst is a fixed value, it is stored in advance in the heat source side control means. The compressor suction refrigerant density is a value obtained by multiplying the saturated gas density calculated from the refrigerant temperature of the use side heat exchanger 5 by a correction coefficient.

Next, the use side control means 14 estimates the cooling capacity Q [kW] from the refrigerant flow rate Gr [kg / h] using the following equation 4 (step S92). This time, the specific enthalpy difference ΔI [kJ / kg] of the evaporator is not calculated and calculated during operation by setting a fixed value in advance and storing it in the heat source side control means 13.
Q = Gr × ΔI / 3.6 / 1000 (4)

  Next, the use side control means 14 obtains the enthalpy Is of the blown air state from the refrigerant temperature Tr (step S93). The blown air state is the same as the saturated air state of the refrigerant temperature of the use side heat exchanger.

  Next, the use side control means 14 calculates | requires enthalpy I1 of suction air using Formula 2 (step S94). Next, the use side control means 14 sets a temporary value as the room humidity Tinwb (step S95), and calculates the enthalpy Iin ′ from this value and the room temperature Tindb detected by the room temperature detecting means 21 (step S95). S96). Then, it is checked whether or not the enthalpy Iin ′ is equal to the enthalpy Iin calculated in step S94. If not, the process returns to step S95. In this way, step S95 to step S97 are repeatedly executed until the enthalpy Iin ′ becomes equal to the enthalpy Iin, thereby changing the indoor humidity Tinwb. And the value of Tinwb when it becomes equal becomes indoor humidity (suction air humidity) which should be calculated.

  FIG. 10 shows a procedure for determining the operation pattern of the drain pump. First, after the cooling operation is started (step S101), first, at a predetermined time, in the use side refrigeration air conditioner Y, the indoor temperature detection means 21 and the refrigerant temperature detection means 23 of the use side heat exchanger 5 are used. The room temperature Tindb and the refrigerant temperature Tr are detected, and the data is transferred to the use side control means 14. On the other hand, the heat source side control means 13 reads the set value of the compressor operating frequency F (step S102). Next, the compressor frequency F is sent from the heat source side control means 13 to the use side control means 14 via the communication means (step S103). Next, the use side control means 14 calculates the refrigerant flow rate Gr and the cooling capacity from the compressor operating frequency F and the refrigerant temperature Tr (step S104). Next, the use side control means 14 calculates | requires indoor air enthalpy Iin from indoor temperature Tindb, refrigerant | coolant temperature Tr, and cooling capacity Q (step S105). The indoor humidity Tinwb is set so that the indoor air enthalpy becomes Iin (step S106).

  The subsequent steps are the same as in the first embodiment. The use side control means 14 calculates the indoor dew point temperature Tro using the indoor temperature Tindb and the indoor humidity Tinwb estimated by the above method (step S107). The dew point temperature can be uniquely obtained from the air diagram of FIG. 3 or can be obtained by the procedure shown in FIG. Next, the use side control means 14 obtains a value ΔT (temperature difference) obtained by subtracting the refrigerant temperature Tr from the dew point temperature Tro (step S108). Next, the usage-side control means 14 determines an operation pattern that combines the operation time and stop time of the drain pump 24 based on the temperature difference ΔT (step S109). FIG. 6 shows an example of the temperature difference ΔT and the drain pump operation pattern. For example, in the No. 4 region, it is determined that the operation pattern of the drain pump 24 is a 3-minute operation and a 3-minute stop. Next, the use side control means 14 operates / stops the drain pump 24 by operating the relay incorporated in the electric circuit of the drain pump 24 (step S110).

  In this description, the dew point temperature is used, but it goes without saying that the absolute humidity of the intake air and the absolute humidity of the saturated air at the refrigerant temperature may be used.

  In this description, a four-way ceiling cassette type indoor unit is assumed as the indoor unit. However, it goes without saying that the same operation and control can be performed with indoor units having other structures such as a ceiling-mounted type and a wall-mounted type.

  In the present description, most of the calculation procedure is performed by the use side control means, but it goes without saying that the calculation may be performed by either the heat source side control means.

  In this description, the cooling capacity is estimated using the compressor operating frequency. However, for the sake of simplicity, the cooling capacity may be given as a constant value in advance. In that case, the procedure of reading the set value of the compressor operating frequency F by the heat source side control means 13 in step S102, the procedure of step S103, and step S104 can be omitted.

  As described above, according to the second embodiment, the compressor, the heat source side heat exchanger, the pressure reducing means, and the use side heat exchanger are sequentially connected in an annular shape by piping, and the heat source that controls the compressor based on the operating frequency. Side control means, a drain side receiving drain water from the use side heat exchanger, a drain pump for discharging drain water from the drain water tray to the outside, and a communication side connecting to the heat source side control means A control means, an indoor temperature detection means for detecting the indoor temperature, and a refrigerant temperature detection means for detecting the refrigerant temperature of the use side heat exchanger, and during the cooling operation, the heat source side control means has an operating frequency of the compressor. Is sent to the use side control means via the communication means, and the use side control means includes a storage means for storing a table in which the temperature difference, the operation time and the stop time of the drain pump are associated with each other, and the cooling operation is performed for a predetermined time. Every heat source The cooling capacity of the use side heat exchanger is calculated based on the operating frequency of the compressor received from the control means, and then the indoor temperature detected by the indoor temperature detection means and the use side heat detected by the refrigerant temperature detection means. The indoor humidity is estimated based on the refrigerant temperature of the exchanger and the calculated cooling capacity of the use side heat exchanger, and then the indoor dew point temperature is calculated based on the indoor temperature and the estimated indoor humidity. The operation time and stop time of the drain pump are determined based on the temperature difference between the indoor dew point temperature and the refrigerant temperature of the use side heat exchanger and the table of the storage means, and then the drain is determined based on the determined operation time and stop time. By controlling the pump, it is possible to avoid unnecessary operation of the drain pump and to reliably remove the necessary drain water.

Embodiment 3 FIG.
Hereinafter, Embodiment 3 of the present invention will be described. Since the refrigerant circuit diagram (FIG. 7), the sectional view of the use side refrigeration air conditioner (FIG. 8), and the refrigerant operation in the cooling operation are the same as those in the second embodiment, the description is omitted.

Features common to the first and second embodiments are shown below. In the first embodiment, it has been explained that the dehumidification amount can be obtained from the difference between the absolute humidity of the intake air and the blown air, the blowing amount, and the cooling capacity. However, since the actual state value of the blown air cannot actually be detected, for example, it is assumed that the blown air state and the saturated air state equivalent to the evaporation temperature of the use side heat exchanger are the same, or the air volume of the blower is set to the maximum The dehumidification amount has been estimated assuming the value.
In other words, if the room temperature, the room humidity, the air flow rate, and the cooling capacity are constant, it is possible to estimate the blowing temperature, the blowing humidity, and the dehumidifying amount that can be obtained from them by calculation or experiment in advance. If the combination fixed values of room temperature, room humidity, air flow, and cooling capacity are several patterns, the drain pump operation pattern is determined from the dehumidification amount obtained by calculation and testing during product development, and stored in the control means in advance. So you can save time and effort.

  For example, in a museum exhibition space, when a stable load state is generated by another refrigeration air conditioner, and as a result, the indoor temperature and the indoor humidity are constantly adjusted, the compressor frequency, the indoor fan motor It is assumed that the number of rotations is fixed at a certain value, and as a result, the cooling capacity and the air flow rate of the use side refrigeration air conditioner are almost constant.

  When the operating side ambient temperature is 35 ° C, the usage side ambient temperature is 27 ° C DB, 19 ° C WB, and the compressor operating frequency, the heat source side and the usage side fan motor speed are constant, the usage side refrigeration air conditioner Y Since the blown air state can be grasped by performing tests and calculations in advance, the dehumidification amount can be grasped with high accuracy. As a result, the drain pump can be operated and stopped with high accuracy under these conditions.

  FIG. 11 shows an example of the test results when the heat source side ambient temperature is 35 ° C., the use side ambient temperature is 27 ° C. DB, and 19 ° C. WB, and the compressor operating frequency, the heat source side, and the use side fan motor speed are constant. Show. The horizontal axis shows the cooling capacity, and the vertical axis shows the refrigerant temperature of the use side heat exchanger. The dew point temperature of the ambient temperature on the use side is 14.6 ° C. It can be seen from FIG. 11 that when the cooling capacity is reduced, the refrigerant temperature increases, and below a certain capacity, the refrigerant temperature exceeds the dew point temperature of the use-side ambient air. Since dehumidification is not possible in this state, moving the drain pump is a waste of power. Therefore, in this case, the drain pump 24 is not moved.

When the refrigeration air conditioner is provided with a switch for making the compressor operating frequency, the heat source side, and the use side fan motor rotation speed constant under conditions where the heat source side ambient temperature and the usage side ambient temperature are constant, the compressor operating frequency The operation pattern of the drain pump can be designed in advance by quantifying the blown air state and dehumidification amount in the test in advance when operating at the fan motor rotation speed on the heat source side and the use side. If the operation pattern is stored in the user-side control means, the operation pattern of the drain pump can be uniquely determined just by turning on the switch, and it is possible to save the trouble of calculating the operation pattern of the drain pump during the cooling operation. .
When the switch is restored, normal control is restored.

  When the refrigeration air conditioner is equipped with a switch to keep the compressor operating frequency, the heat source side, and the use side fan motor rotation speed constant under conditions where the heat source side ambient temperature and the use side ambient temperature are constant, the cooling capacity lower than the rating May be intended to be implemented continuously. It is necessary to quantify the blown air condition and dehumidification amount in advance by tests, but when the cooling capacity is less than 50% of the rated ratio, the dehumidification amount is often zero or very small. In that case, the operation pattern of the drain pump is always stopped or continuously stopped for 2 hours or more.

  According to Embodiment 3 of the present invention, the compressor, the heat source side heat exchanger, the pressure reducing means, and the use side heat exchanger are sequentially connected in an annular shape by piping, and the compressor, the heat source side heat exchanger, and the pressure reducing means are connected. A heat source side refrigeration air conditioner having a heat source side control means, a use side heat exchanger, a blower fan that sends room air to the use side heat exchanger, and a drain that stores drain water from the use side heat exchanger A use-side refrigeration air conditioner having a water tray, a drain pump that discharges drain water from the drain water tray to the outside, a use-side control means, and a refrigerant temperature detection means that detects the refrigerant temperature of the use-side heat exchanger The use side control means includes storage means for storing the indoor dew point temperature, and the ambient temperature of the heat source side refrigeration air conditioner and the ambient temperature of the use side refrigeration air conditioner are substantially constant within ± 0.5 ° C. In the compressor operating frequency, heat source side, When it is known that the cooling operation is performed at a constant fan motor rotational speed, the temperature difference between the refrigerant temperature of the use-side heat exchanger detected by the refrigerant temperature detection means and the indoor dew point temperature stored in the storage means The drain pump operation time and stop time are determined on the basis of the flow rate, and then the drain pump is controlled based on the determined operation time and stop time, thereby avoiding unnecessary drain pump operation and removing necessary drain water. It can be done reliably.

It is a refrigerant circuit figure in Embodiment 1 of the present invention. It is sectional drawing of the utilization side refrigeration air conditioner Y in Embodiment 1 of this invention. It is an air line figure in Embodiment 1 of this invention. It is the procedure which determines the drain pump operation pattern in Embodiment 1 of this invention. It is a procedure which calculates | requires the dew point temperature in Embodiment 1 of this invention. FIG. 5 is a relationship diagram between a temperature difference ΔT and a drain pump operation pattern in Embodiment 1 of the present invention. It is a refrigerant circuit figure in Embodiment 2 of this invention. It is sectional drawing of the utilization side refrigerating air conditioner in Embodiment 2 of this invention. It is a procedure which estimates the indoor humidity in Embodiment 2 of this invention. It is the procedure which determines the drain pump operation pattern in Embodiment 2 of this invention. It is a related figure of the cooling capacity of Embodiment 3 of this invention, and the refrigerant | coolant temperature of a utilization side heat exchanger.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Compressor, 2 Four way valve, 3 Heat source side heat exchanger, 4 Pressure reduction means, 5 Use side heat exchanger, 6 Low pressure liquid reservoir, 7 Gas extension piping, 8 Liquid extension piping, 9 Heat source side ventilation fan, 10 Heat source side Blower fan motor, 11 user-side fan, 12 user-side fan motor, 13 heat source side control means, 14 user side control means, X heat source side refrigeration air conditioner, Y user side refrigeration air conditioner, 21 indoor temperature detection means, 22 Indoor humidity detection means, 23 refrigerant temperature detection means of use side heat exchanger, 24 drain pump, 25 drain water tray, 26 drain water discharge pipe.

Claims (12)

The compressor, the heat source side heat exchanger, the pressure reducing means, and the use side heat exchanger are sequentially connected in an annular shape by piping,
Heat source side control means for controlling based on the operating frequency of the compressor;
A drain side receiving means for storing drain water from the use side heat exchanger, a drain pump for discharging the drain water from the drain water receiving tray to the outside, and a use side control means having communication means connected to the heat source side control means. And an indoor temperature detecting means for detecting the indoor temperature, and a refrigerant temperature detecting means for detecting the refrigerant temperature of the use side heat exchanger,
During cooling operation, the heat source side control means sends the operating frequency of the compressor to the use side control means via the communication means,
The use side control means cools the use side heat exchanger based on the operating frequency of the compressor received from the heat source side control means and the refrigerant temperature of the use side heat exchanger every predetermined time during cooling operation. The first enthalpy indicating the enthalpy of the blown air state is calculated based on the refrigerant temperature of the use side heat exchanger detected by the refrigerant temperature detecting means, and the calculated first enthalpy is calculated. And calculating the second enthalpy indicating the enthalpy of the intake air on the basis of the calculated cooling capacity of the use side heat exchanger, and then changing the indoor humidity, the indoor humidity and the indoor temperature detecting means The third enthalpy is calculated from the detected indoor temperature, and the calculated third enthalpy is compared with the second enthalpy to determine the indoor humidity when the room humidity becomes equal. Estimated that calculates the room dew point temperature then based on the indoor temperature detection means room humidity was the presumed detected room temperature by the next and the indoor dew point temperature and the calculated detected by said refrigerant temperature detecting means wherein determining the operating time and stop time of the drain pump, then to control the drain pump based on the operating time and stop time and the determined on the basis of the temperature difference between refrigerant temperature of the utilization side heat exchanger A refrigeration air conditioner characterized by that.   The refrigerating and air-conditioning apparatus according to claim 1, wherein the usage-side control means calculates the second enthalpy by the following equation (1).
      Iin = Is + Q / G ......... (1)
  Where Iin is the second enthalpy, Is is the first enthalpy, Q is the cooling capacity of the use side heat exchanger, and G is the use side air flow The usage-side control means includes storage means for storing a table in which the temperature difference between the refrigerant temperature and the indoor dew point temperature of the usage-side heat exchanger and the operation time and stop time of the drain pump are associated with each other.
Based on the temperature difference between the refrigerant temperature of the use side heat exchanger detected by the refrigerant temperature detection means and the indoor dew point temperature of the storage means, and the operation time and stop time of the drain pump based on the table of the storage means The refrigeration air conditioner according to claim 1 or 2 , wherein the refrigeration air conditioner is determined. The coolant temperature detecting means of the use-side heat exchanger, near the center of the pipe path which constitutes the heat exchanger, to any one of claims 1 to 3, characterized in that it is installed in contact with the pipe Refrigeration air conditioner of description. The coolant temperature detecting means of the use-side heat exchanger is installed in two locations in the vicinity of the cooling time of the inlet and near the center of the pipe path which constitutes the heat exchanger,
The utilization-side control unit, of the temperature at which the two refrigerant temperature detecting means detected during cooling operation, a refrigeration according lower the to any one of claims 1 to 3, characterized in that considered as the refrigerant temperature Air conditioner. The utilization-side control unit, when the refrigerant temperature of the utilization side heat exchanger is detected by the refrigerant temperature detecting means of the use side heat exchanger at predetermined time is higher than a predetermined value, stops the drain pump The refrigerating and air-conditioning apparatus according to any one of claims 1 to 3 , wherein the refrigerating and air-conditioning apparatus is continued. The refrigerating and air-conditioning apparatus according to claim 6 , wherein the predetermined value is the dew point temperature or a temperature near the dew point temperature. A switch for cooling operation by setting the operating frequency of the compressor, the heat source side, the fan motor rotation number on the use side to a predetermined fixed value,
The refrigerating and air-conditioning apparatus according to any one of claims 1 to 3 , wherein the usage-side control unit controls the drain pump with a specific operation pattern while the switch is turned on. The operation frequency of the compressor, the heat source side, the fan motor rotation speed on the use side is set to a predetermined fixed value for cooling operation, and a dedicated switch that makes the cooling capacity of the use side heat exchanger less than rated,
The refrigerating and air-conditioning apparatus according to any one of claims 1 to 3 , wherein the user-side control means continues to stop the drain pump while the switch is turned on. The compressor, the heat source side heat exchanger, the pressure reducing means, and the use side heat exchanger are sequentially connected in an annular shape by piping,
Heat source side control means for controlling based on the operating frequency of the compressor;
Drain water receiving tray for storing drain water from the use side heat exchanger, a drain pump for discharging drain water from the drain water receiving tray to the outside, and use side control means having communication means connected to the heat source side control means. And an indoor temperature detecting means for detecting the indoor temperature and a refrigerant temperature detecting means for detecting the refrigerant temperature of the use side heat exchanger,
During cooling operation, the heat source side control means sends the operating frequency of the compressor to the user side control means via the communication means;
During the cooling operation, the utilization side heat exchanger cools the utilization side heat exchanger based on the operating frequency of the compressor received from the heat source side control means by the utilization side control means and the refrigerant temperature of the utilization side heat exchanger every predetermined time. Calculating steps,
A step of calculating a first enthalpy indicating an enthalpy of a blown air state based on a refrigerant temperature of the usage side heat exchanger detected by the refrigerant temperature detection unit by the usage side control unit ;
A step of calculating a second enthalpy indicating the enthalpy of the intake air based on the calculated first enthalpy and the calculated cooling capacity of the use side heat exchanger by the use side control means;
Calculating the third enthalpy from the indoor humidity and the indoor temperature detected by the indoor temperature detecting means while the usage-side control means changes the indoor humidity;
A step of comparing the calculated third enthalpy with the second enthalpy by the use side control means and estimating the indoor humidity to be obtained when equalized;
Calculating the room dew point temperature based on the room humidity the utilization-side control unit has the estimated indoor temperature detected by the indoor temperature detection means,
Calculating a temperature difference between the indoor dew point calculated by the use side control means and the refrigerant temperature of the use side heat exchanger detected by the refrigerant temperature detection means ;
A step of determining an operation time and a stop time of the drain pump based on the calculated temperature difference by the use side control means;
And a step of controlling the drain pump based on the determined operation time and stop time by the use side control means.   In the step of calculating the second enthalpy based on the first enthalpy and the cooling capacity of the use side heat exchanger, the use side control means uses the following formula (1). The refrigerating and air-conditioning method according to claim 10.
      Iin = Is + Q / G ......... (1)
  Where Iin is the second enthalpy, Is is the first enthalpy, Q is the cooling capacity of the use side heat exchanger, and G is the use side air flow The usage-side control means stores in the storage means a table in which the temperature difference between the refrigerant temperature of the usage-side heat exchanger and the indoor dew point temperature and the operation time and stop time of the drain pump are associated with each other. In the step of determining the operation time and stop time of the drain pump, the temperature difference between the refrigerant temperature of the use side heat exchanger detected by the refrigerant temperature detection means and the indoor dew point temperature stored in the storage means is calculated. The refrigeration and air conditioning method according to claim 10 or 11 , wherein the operation time and stop time of the drain pump are determined based on the calculated temperature difference and a table stored in the storage means. .

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