JP6803985B2 - Outside air temperature detection system for heat pump heat source machine - Google Patents

Description

An embodiment of the present invention relates to an outside air temperature detection system for a heat pump heat source machine.

The air conditioner outdoor unit described in Patent Document 1 is configured to allow air to flow to the outdoor heat exchanger by a blower fan, is located on the upstream side of the air flow of the outdoor heat exchanger, and receives radiant heat from the outdoor heat exchanger. It has an outside air temperature sensor at the affected position. In addition, this air conditioner outdoor unit stops the output of the detected outside air temperature when the amount of air flowing through the outdoor heat exchanger decreases, and pseudo-outputs the detected outside air temperature immediately before the stop as the subsequent outside air temperature. Provide correction means.

Japanese Patent No. 3019081

However, in the above-mentioned air conditioner outdoor unit, if the outside air temperature correction means stops the output of the detected outside air temperature and then the operation is continued for a long time in this state, the detected value of the outside air temperature detected by the outside air temperature sensor becomes. It will not be updated for a long time as the outside air temperature used for control. For this reason, the compressor cannot be controlled using the accurately detected value of the outside air temperature, and there is a risk that efficient operation of the refrigeration cycle cannot be realized.

The embodiment of the present invention has been made in consideration of the above circumstances, and the outside air temperature sensor installed in the condenser or evaporator that exchanges heat between the air blown from the blower fan and the refrigerant is the blower fan. It is an object of the present invention to provide an outside air temperature detection system for a heat pump heat source machine that can accurately detect the outside air temperature even when the amount of air blown by the heat pump is low.

The outside air temperature detection system of the heat pump heat source machine according to the embodiment of the present invention has a refrigeration cycle in which a compressor, a condenser, an expansion valve and an evaporator having variable operating frequencies are sequentially connected to circulate the refrigerant, and the condensation One of the compressor and the compressor is provided with a blower fan, and an outside air temperature sensor that exchanges heat between the air blown from the blower fan and the refrigerant and further detects the outside air temperature is provided and detected by the outside air temperature sensor. In a heat pump heat source machine in which the compressor and the blower fan are controlled by a control device based on the detected value of the outside air temperature, when the amount of air blown by the blower fan is less than a predetermined value, the detection from the outside air temperature sensor is performed. When the value is not used for control by the control device and the amount of air blown by the blower fan is less than a predetermined value, the amount of air blown by the blower fan is set to a constant value equal to or higher than the predetermined value and blown at that time. driving the blower fan is set to a predetermined time period, the detection value of the detected outside air temperature by the outside air temperature sensor during the operation end is configured to be used to control by the control unit, the blower fan The constant value of the air blowing amount and the constant time of the air blowing time at that time are set differently according to the operating frequency of the compressor .

The system diagram which shows the refrigeration cycle of the heat pump heat source machine to which the outside air temperature detection system of the heat pump heat source machine which concerns on one Embodiment is applied. The block diagram which shows the control system which has the control device of FIG. Explanatory drawing explaining the zone of the outside air temperature detected by the outside air temperature sensor of FIG. The chart which shows the relationship between the rotation speed of the 1st and 2nd blower fans of FIG. 1 and a fan tap. The relationship between each zone of the outside air temperature in FIG. 3, the operating frequency of the compressor in FIG. 1 and the fan tap in FIG. 4 is shown, (A) is a chart for the first blower fan, and (B) is a chart for the second blower fan. .. A chart showing the fan tap and operation duration during operation of both fans, which are carried out to update the outside air temperature used for control, in relation to the operating frequency of the compressor. FIG. 5 is a flowchart showing a control procedure of a main routine of a blower fan mainly executed by the control device of FIG. FIG. 3 is a flowchart showing a control procedure of a subroutine of a blower fan mainly executed by the control device of FIG.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a system diagram showing a refrigeration cycle of a heat pump heat source machine to which the outside air temperature detection system of the heat pump heat source machine according to the embodiment is applied. The heat pump heat source machine 10 shown in FIG. 1 includes a compressor 12, a four-way valve 13, a condenser (air heat exchanger 14 or water heat exchanger 15), an expansion valve 16, and an evaporator (water heat exchanger 15 or air heat). The exchanger 14), the four-way valve 13, and the accumulator 17 are sequentially connected by the refrigerant pipe 18, and have a refrigeration cycle 11 in which the refrigerant circulates.

That is, in the refrigeration cycle 11, at the cooling operation switching position of the four-way valve 13, the compressor 12, the four-way valve 13, the air heat exchanger 14 as the condenser, the expansion valve 16, the water heat exchanger 15 as the evaporator, and the four-way valve 13 The valve 13 and the accumulator 17 are sequentially connected by the refrigerant pipe 18, so that the refrigerant circulates in an annular shape. Although not shown, the refrigeration cycle 11 is a compressor 12, a four-way valve 13, a water heat exchanger 15 as a condenser, an expansion valve 16, and air heat exchange as an evaporator at the heating operation switching position of the four-way valve 13. The vessel 14, the four-way valve 13, and the accumulator 17 are sequentially connected by the refrigerant pipe 18, so that the refrigerant circulates in a ring shape.

Here, the compressor 12 compresses the refrigerant and discharges it in a high temperature and high pressure state. The refrigerant used in this embodiment is, for example, R410A or R32. Further, the expansion valve 16 depressurizes the refrigerant to bring it into a low temperature and low pressure state. Further, the four-way valve 13 switches the flow of the refrigerant in the refrigeration cycle 11, and as described above, switches the flow of the refrigerant between the heating operation and the cooling operation.

The air heat exchanger 14 is a combination of air and refrigerant blown from a plurality of units, for example, two blower fans (first blower fan 21, second blower fan 22) installed in the vicinity of the air heat exchanger 14. Heat exchange between them. For example, the first blower fan 21 is located below the air heat exchanger 14 and far from the outside air temperature sensor 34 (described later), and the second blower fan 22 is located above the air heat exchanger 14 and outside the outside air temperature sensor 34. It will be installed at a position close to. Further, the water heat exchanger 15 exchanges heat between the refrigerant and water (specifically, water or antifreeze; the same applies hereinafter), and is connected to the load 24 via the water pipe 23. A circulation pump 25 that rotates at a constant speed is provided in the water pipe 23, and by the action of the circulation pump 25, the water is circulated between the water heat exchanger 15 and the load 24 by the water pipe 23. The water is cooled or heated.

The change of state and action of the refrigerant during the cooling operation of the refrigeration cycle 11 described above will be described with reference to FIG. The high-temperature and high-pressure refrigerant discharged from the compressor 12 passes through the four-way valve 13 and exchanges heat with the air (outside air) guided by the blower fans 21 and 22 at the air heat exchanger (condenser) 14, dissipates heat and condenses. To do. The refrigerant condensed by the air heat exchanger 14 changes to a low temperature and low pressure state by the expansion valve 16 and flows into the water heat exchanger (evaporator) 15. The low-temperature low-pressure refrigerant exchanges heat with water in the water heat exchanger 15 and evaporates, and cools the water by endothermic heat. The refrigerant evaporated in the water heat exchanger 15 flows into the accumulator 17 through the four-way valve 13 and then is returned to the compressor 12.

In addition, the state change and action of the refrigerant during the heating operation of the refrigeration cycle 11 will be described. The high-temperature and high-pressure refrigerant discharged from the compressor 12 passes through the four-way valve 13 and exchanges heat with water in the water heat exchanger 15 to condense and heat the water by heat dissipation. The refrigerant condensed by the water heat exchanger 15 changes to a low temperature and low pressure state by the expansion valve 16 and flows into the air heat exchanger 14. The low-temperature low-pressure refrigerant exchanges heat with the air (outside air) guided by the blower fans 21 and 22 in the air heat exchanger 14, absorbs heat, and evaporates. The evaporated refrigerant flows into the accumulator 17 via the four-way valve 13 and then is returned to the compressor 12. The following description describes a case where the air heat exchanger 14 functions as a condenser during the cooling operation of the refrigeration cycle 11.

As shown in FIG. 1, a discharge side pressure sensor 26 and a discharge side temperature sensor 28 are installed on the discharge side of the compressor 12, and a suction side pressure sensor 27 and a suction side temperature sensor 29 are installed on the suction side in the refrigerant pipe 18. Will be done. Further, in the refrigerant pipe 18, a condenser outlet temperature sensor 30 is installed on the outlet side of the air heat exchanger 14, and an evaporator inlet temperature sensor 31 is installed on the inlet side of the water heat exchanger 15. Further, in the water pipe 23, a water inlet temperature sensor 32 is installed on the inlet side to the water heat exchanger 15, and a water outlet temperature sensor 33 is installed on the outlet side from the water heat exchanger 15. Further, the air heat exchanger 14 is provided with an outside air temperature sensor 34 that detects the outside air temperature TO.

The detected values of the above-mentioned sensors 26 to 34 are input to the control device 35 shown in FIGS. 1 and 2. The control device 35 controls the compressor 12, the four-way valve 13, the expansion valve 16, the first blower fan 21, and the second blower fan 22 based on the detected values from the sensors 26 to 34.

For example, the control device 35 activates the compressor 12 when the detected value (water outlet temperature TWO) of the water outlet temperature sensor 33 becomes larger than the water outlet temperature threshold (target water outlet temperature bTWOs + offset ON), and the refrigeration cycle 11 To start the cooling operation. Further, the control device 35 stops the compressor 12 when the detected value (water inlet temperature TWI) of the water inlet temperature sensor 32 becomes equal to or less than the water inlet temperature threshold (target water inlet temperature bTWIs).

Further, the control device 3 controls the compressor 12, the first blower fan 21, and the second blower fan 22 based on the detected value of the outside air temperature sensor 34. For example, when the detected value (outside air temperature TO) of the outside air temperature sensor 34 at the start of the cooling operation of the refrigeration cycle 11 is lower than the predetermined outside air temperature low threshold value (when it is in the T zone described later), the control device 35 Stops the first blower fan 21 to perform one-sided fan operation in which only the second blower fan 22 is operated, and lowers the operating frequency of the compressor 12.

Generally, when the outside air temperature TO is low, the heat dissipation capacity of the air heat exchanger 14 as a condenser is high, so that the rotation speeds of the first blower fan 21 and the second blower fan 22 are lowered, and the compressor 12 It becomes possible to set the operating frequency low. Therefore, when the outside air temperature TO is lower than the predetermined outside air temperature low threshold value, one-sided fan operation in which only the second blower fan 22 is operated becomes possible.

Here, the control device 35 divides the outside air temperature TO into each zone (T zone, S zone, R zone, Q zone, P zone, O zone, U zone) shown in FIG. 3, and detects it by the outside air temperature sensor 34. In particular, the first blower fan 21 and the second blower fan 22 are controlled for each zone to which the detected value of the outside air temperature TO corresponds. For example, when the outside air temperature TO is in the T zone, one-sided fan operation is performed in which only the second blower fan 22 is operated. Each zone of the outside air temperature TO is provided with a 1K (Kelvin) differential when the temperature rise and fall zones are changed. This prevents abrupt and frequent changes in the refrigeration cycle 11 when the zone is changed.

Further, the control device 35 controls the fan rotation speeds of the first blower fan 21 and the second blower fan 22 by using the fan tap shown in FIG. Here, assuming that the rotation speed of the first blower fan is m1, m2, m3, ..., M14, m15 (m1 <m2 <m3 <... <m14 <m15), the rotation speed of the second blower fan is It is set as m1, m2-α, m3-α, ..., M14-α, m15-α. That is, the rotation speed of the first blower fan 21 is set to a rotation speed that is α higher than the rotation speed of the second blower fan 22. At the minimum rotation speed, the same rotation speed is set. For example, when the minimum rotation speed is m1 = 200 rps and α = 20, when the first blower fan 21 and the second blower fan 22 are controlled by the fan tap W5, the first blower fan 21 has m5 = 360 rps. The rotation speed of the second blower fan 22 is controlled as m5-α = 340 rps.

Further, as shown in FIG. 5, the control device 35 sets the maximum and minimum values of the rotation speeds of the first blower fan 21 and the second blower fan 22 to the zone of the outside air temperature TO and the operating frequency of the compressor 12. It is determined by f, and the rotation speeds of the first blower fan 21 and the second blower fan 22 are controlled within the range of the maximum value and the minimum value. Further, the control device 35 sets the maximum and minimum values of the rotation speeds of the first blower fan 21 and the second blower fan 22 shown in FIG. 5 by the detection value (discharge side temperature TD) of the discharge side temperature sensor 28 and the discharge side temperature TD. It is corrected by the detected value of the condenser outlet temperature sensor 30 (condenser outlet temperature TE).

By the way, as shown in FIG. 1, a part of the first blower fan 21 and the second blower fan 22 is operated (that is, the first blower fan 21 is stopped and only the second blower fan 22 is operated). During single fan operation, the amount of air flowing through the air heat exchanger 14 as a condenser decreases, so the outside air temperature sensor 34 installed in the air heat exchanger 14 is affected by the radiant heat from the air heat exchanger 14. As a result, the outside air temperature TO cannot be detected accurately. Therefore, the control device 35 does not take in the detected value from the outside air temperature sensor 34 and is not used for control during the operation of the single fan when the amount of air flowing through the air heat exchanger 14 is less than a predetermined value.

However, when one-fan operation lasts for a long time, the outside air temperature TO may fluctuate significantly, and even in this case, the control device 35 uses the detection value of the outside air temperature TO detected by the outside air temperature sensor 34. If this is not possible, efficient operation of the refrigeration cycle 11 in response to changes in the outside air temperature TO cannot be performed.

Therefore, in the present embodiment, the control device 35 uses the first blower fan 21 and the second blower fan 22 at predetermined time intervals during operation of the single fan when the amount of air flowing in the air heat exchanger 14 becomes less than a predetermined value. Both fans are operated (that is, the first blower fan 21 and the second blower fan 22 are operated together), and the amount of blown air flowing through the air heat exchanger 14 is set to a constant value equal to or higher than the predetermined value. Moreover, the ventilation time at that time is set to a fixed time.

Here, every predetermined time is a time interval in which the outside air temperature does not fluctuate significantly, for example, every two hours. Further, for a constant value of the amount of air flowing in the air heat exchanger 14 and a constant time of the blowing time at that time, the execution of both fan operations does not affect the refrigeration cycle 11, and the air heat exchanger as a condenser The outside air temperature sensor 34 installed in the 14 is the minimum value that is not affected by the radiant heat from the air heat exchanger 14.

Further, a constant value of the amount of air flowing in the air heat exchanger 14 and a constant time of the blowing time at that time are set differently according to the operating frequency f of the compressor 12, as shown in FIG. For example, the fan rotation speed (fan tap FT) that realizes a constant value of the amount of air blown through the air heat exchanger 14 and the fixed time of the air blow time at that time (that is, the operation duration TA) are the operations of the compressor 12. When the frequency f is f <30, the fan tap FT becomes W5, the operation duration TA becomes 10 minutes, and when the operating frequency of the compressor 12 is high f ≧ 45, the fan tap FT becomes W7 and the fan rotates. The number will increase, and the operation duration TA will be shortened to 6 minutes.

The control device 35 executes both fan operations at predetermined time of single fan operation as described above, and sets the amount of air flowing through the air heat exchanger 14 to a constant value and the air blowing time at that time to a constant time. At the end of the above-mentioned operation of both fans, the detected value of the outside air temperature TO detected by the outside air temperature sensor 34 is taken in, and the outside air temperature TO used for control is updated using this detected value.

Further, the control device 35 operates the first blower fan 21 and the second blower fan 22 installed in the vicinity of the air heat exchanger 14 as the condenser even when the compressor 12 is stopped (both fan operations). ), The amount of air blown by the first blower fan 21 and the second blower fan 22 flowing in the air heat exchanger 14 is set to a constant value, and the blower time at that time is set to a constant time.

In this case, the outside air temperature sensor 34 installed in the air heat exchanger 14 determines the constant value of the amount of air blown by the first blower fan 21 and the second blower fan 22 and the fixed time of the blower time at that time. This is the minimum value that is not affected by the radiant heat from. Further, the fan rotation speed (fan tap FT) that realizes a constant value of the amount of air blown through the air heat exchanger 14 and the fixed time of the air blow time at that time (that is, the operation duration TA) are as shown in FIG. In addition, when the operating frequency f of the compressor 12 is f = 0, the fan tap FT is W5, and the operation duration TA is 3 minutes.

As described above, the control device 35 operates both fans when the compressor 12 is stopped, and keeps the amount of air blown by the first blower fan 21 and the second blower fan 22 flowing in the air heat exchanger 14 at a constant value. At the end of the operation of both fans in which the ventilation time at that time is set to a fixed time, the detected value of the outside air temperature TO detected by the outside air temperature sensor 34 is taken in, and this detected value is used to use the outside air temperature TO used for control. To update.

Next, the control procedure of the first blower fan 21 and the second blower fan 22 executed by the control device 35 will be described with reference to FIGS. 7 and 8.
As shown in FIG. 7, the control device 35 determines whether or not the detected value (water outlet temperature TWO) of the water outlet temperature sensor 33 is larger than the water outlet temperature threshold (target water outlet temperature bTWOs + offset ON). (S1), when it is large, the compressor 12 is started to start the cooling operation in the refrigeration cycle 11 (S2).

Next, the control device 35 determines whether or not the detected value of the outside air temperature TO detected by the outside air temperature sensor 34 corresponds to the T zone (see FIG. 3) (S3). When the detected value of the outside air temperature TO is in any of the S zone to the U zone (see FIG. 3) other than the T zone, the control device 35 is the first installed in the vicinity of the air heat exchanger 14 as a condenser. Both fan operations are carried out in which the blower fan 21 and the second blower fan 22 are operated together (S4).

In step S3, when the detected value of the outside air temperature TO is in the T zone, the control device 35 performs a one-sided fan operation in which the first blower fan 21 is stopped and the second blower fan 22 is operated (S5). Next, the control device 35 determines whether or not a predetermined time, that is, the duration of the single fan operation has elapsed, for example, 2 hours since the start of the single fan operation in step S5 (S6).

The control device 35 returns to step S3 when the operation duration of one-fan operation has not elapsed, for example, 2 hours in step S6, and when it has elapsed, both the first blower fan 21 and the second blower fan 22 are used. The fan operation is performed (S7). In both fan operations, the rotation speeds of the second blower fan 21 and the second blower fan 22 are determined based on the fan tap FT (see FIG. 6) determined by the operating frequency f of the compressor 12.

The control device 35 determines whether or not the operation continuation time after starting the operation of both fans in step S7 has reached the operation continuation time TA (see FIG. 6) (S8). When the operation duration of both fan operations has not reached the operation duration TA in step S8, the control device 35 continues the operation of both fans in step S7.

When the operation duration of both fan operations reaches the operation duration TA in step S8, the control device 35 takes in the detected value of the outside air temperature TO detected by the outside air temperature sensor 34, and controls using this detected value. The outside air temperature TO used for is updated (S4). This updated outside air temperature TO is used for the control after step S1.

After the start of the cooling operation of the refrigeration cycle 11 in step S2 of FIG. 7, in the control device 35, as shown in FIG. 8, the detected value (water inlet temperature TWI) of the water inlet temperature sensor 32 is the water inlet temperature threshold (target water). It is determined whether or not the temperature is below the inlet temperature bTWIs (S11), and when the temperature is below the temperature, the compressor 12 is stopped (S12).

After stopping the compressor 12 in step S12, the control device 35 causes both fan operations by the first blower fan 21 and the second blower fan 22 (S13). In both fan operations, the rotation speeds of the first blower fan 21 and the second blower fan 22 are determined by the fan tap FT (W5) when the operating frequency f of the compressor 12 is f = 0, as shown in FIG. It is determined.

The control device 35 determines whether or not the operation continuation time after starting the operation of both fans in step S13 has reached the operation continuation time TA (S14). As shown in FIG. 6, the operation duration TA is the operation duration TA (3 minutes) when the operation frequency f of the compressor 12 is f = 0.

When the operation duration of both fan operations has not reached the operation duration TA in step S14, the control device 35 continues the operation of both fans in step S13. When the operation duration of both fan operations reaches the operation duration TA in step S14, the control device 35 takes in the detected value of the outside air temperature TO detected by the outside air temperature sensor 34, and controls using this detected value. The outside air temperature TO used for is updated (S15). This updated outside air temperature TO is used for the control after step S1 shown in FIG.

Since it is configured as described above, according to the present embodiment, the following effects (1) to (3) are obtained.
(1) As shown in FIGS. 1 and 7, the control device 35 is a piece in which the amount of air blown by the first blower fan 21 and the second blower fan 22 in the air heat exchanger 14 as a condenser is less than a predetermined value. Both fan operations are performed in which the first blower fan 21 and the second blower fan 22 are operated together at predetermined time (for example, 2 hours) during the fan operation.

In both fan operations, the amount of air blown in the air heat exchanger 14 by the first blower fan 21 and the second blower fan 22 is set to a constant value equal to or higher than the predetermined value, and the blower time at that time is set to a constant time. As shown in FIG. 6, each of the constant value of the blast amount and the constant time of the blast time is determined by the fan tap FT and the operation duration TA determined by the operating frequency f of the compressor 12. At the end of the above-mentioned operation of both fans, the control device 35 takes in the detected value of the outside air temperature TO detected by the outside air temperature sensor 34, and uses this detected value to update the outside air temperature TO used for control.

Therefore, the outside air temperature sensor 34 installed in the air heat exchanger 14 is operated during single fan operation in which the amount of air blown in the air heat exchanger 14 by the first blower fan 21 and the second blower fan 22 is as low as less than a predetermined value. Even if it is affected by the radiant heat from the air heat exchanger 14, the outside air temperature sensor 34 becomes the air heat exchanger by the end of the above-mentioned operation of both fans, which is carried out at predetermined time intervals during the operation of one fan. The outside air temperature TO can be accurately detected without being affected by the radiant heat from 14. As a result, the outside air temperature TO used for control is updated by using the accurately detected outside air temperature detection value, so that the compressor 12 is properly controlled by this outside air temperature, and the heat pump heat source machine 10 The refrigeration cycle 11 can be operated efficiently.

(2) As shown in FIGS. 1 and 8, after the operation of the compressor 12 is stopped, the control device 35 operates both the first blower fan 21 and the second blower fan 22 in the air heat exchanger 14. Both fans are operated so that the amount of air blown is a constant value and the air blown time at that time is a fixed time. The constant value of the amount of air blown in the air heat exchanger 14 in both fan operations is determined by the fan rotation speed determined by the fan tap FT when the operating frequency f of the compressor 12 in FIG. 6 is f = 0. The constant time of the air blowing time is determined by the operation duration TA when the operation frequency f of the compressor 12 in FIG. 6 is f = 0. At the end of the above-mentioned operation of both fans, the control device 35 takes in the detected value of the outside air temperature TO detected by the outside air temperature sensor 34, and uses this detected value to update the outside air temperature TO used for control.

Therefore, by ending the above-mentioned operation of both fans, which is carried out after the compressor 12 is stopped, the outside air temperature sensor 34 can accurately detect the outside air temperature TO without being affected by heat radiation from the air heat exchanger. .. As a result, the outside air temperature TO used for control is updated by using the accurately detected value of the outside air temperature TO, so that the compressor 12 is properly controlled by the outside air temperature TO, and the heat pump heat source. The refrigeration cycle 11 of the machine 10 can be operated efficiently.

(3) As shown in FIG. 6, in the operation of both fans carried out to update the outside air temperature TO used for control, the operating frequencies f of the compressor 12 are as high as f ≧ 45 and 30 ≦ f <45. Is able to shorten the operation duration TA of both fan operations as compared with the case where f <30 is low. Therefore, in particular, when the outside air temperature is low and one fan operation should be originally performed, the refrigeration cycle 11 of the heat pump heat source machine 10 can be efficiently operated by shortening the operation of both fans as described above.

Although the embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. This embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention, and the replacements and changes thereof can be made. , It is included in the scope and gist of the invention, and is also included in the scope of the invention described in the claims and the equivalent scope thereof.

For example, in the present embodiment, the case where the air heat exchanger 14 in which the outside air temperature sensor 34 is installed functions as a condenser has been described, but even when the air heat exchanger 14 functions as an evaporator, one fan Both fans are operated at predetermined time intervals during operation or when the compressor 12 is stopped so that the amount of air blown is a constant value and the air blow time at that time is a certain time, and at the end of the operation of both fans. The outside air temperature TO used for control may be updated by using the detected value of the outside air temperature TO detected by the outside air temperature sensor 34.

10 ... Heat pump heat source machine, 11 ... Refrigeration cycle, 12 ... Compressor, 14 ... Air heat exchanger (condenser, evaporator), 15 ... Water heat exchanger (evaporator, condenser), 16 ... Expansion valve, 21 ... 1st blower fan, 22 ... 2nd blower fan, 34 ... outside air temperature sensor, 35 ... control device, f ... operating frequency, TO ... outside air temperature.

Claims (3)

It has a refrigeration cycle in which a compressor, a condenser, an expansion valve and an evaporator whose operating frequency is variable are sequentially connected to circulate the refrigerant.
One of the condenser and the evaporator is provided with a blower fan, and is also provided with an outside air temperature sensor that exchanges heat between the air blown from the blower fan and the refrigerant and further detects the outside air temperature.
In the heat pump heat source machine in which the compressor and the blower fan are controlled by the control device based on the detected value of the outside air temperature detected by the outside air temperature sensor.
When the amount of air blown by the blower fan is less than a predetermined value, the value detected from the outside air temperature sensor is not used for control by the control device.
Every predetermined time when the amount of air blown by the blower fan is less than a predetermined value, the amount of air blown by the blower fan is set to a constant value equal to or higher than the predetermined value, and the air blow time at that time is set to a certain time. It is configured so that the detection value of the outside air temperature detected by the outside air temperature sensor at the end of the operation is used for control by the control device .
An outside air temperature detection system for a heat pump heat source machine, characterized in that a constant value of the amount of air blown by the blower fan and a certain time of the air blow time at that time are set differently according to the operating frequency of the compressor. .. Multiple blower fans are installed,
When a part of the blower fan is operated, the amount of air blown by the blower fan becomes less than a predetermined value, and when all of the blower fans are operated, the amount of air blown by the blower fan is a constant value and its value. The outside air temperature detection system for a heat pump heat source machine according to claim 1 , wherein the ventilation time is set to a fixed time. When the amount of air blown by the blower fan is set to a constant value and the blowing time at that time is set to a fixed time, the outside air temperature sensor installed in the condenser or the evaporator causes the radiant heat from the condenser or the evaporator. The outside air temperature detection system of the heat pump heat source machine according to claim 1 or 2 , wherein the system is configured so as not to be affected by the above.

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