JP2003042588A - Absorption type cooling and heating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent freezing due to super-cool in an evaporator and permit the continuation of cooling operation without interrupting the same, even under a condition that a feed water temperature is low and the temperature of circulating cooling water is also low upon starting the cooling operation in an absorption type cooling and heating machine. SOLUTION: The temperature of cooling water is detected by a cooling water thermistor upon starting cooling operation. When the detected temperature is determined as lower than a predetermined temperature (25 deg.C for example), a cooling tower fan for a cooling tower is stopped. According to this operation, an excessive absorbing capacity of an absorber is prevented by stopping the circulation of the cooling water whereby the freezing of the evaporator is prevented and the cooling operation is effected without causing any trouble. Further, when the temperature of cooling water has become higher than 28 deg.C, for example, after stopping the cooling tower fan, the operation of the cooling tower fan is re-started.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention forms an absorption cycle by using an aqueous solution of lithium bromide or the like as an absorption liquid during cooling operation, and cools or chills water cooled by an evaporator during the operation of the absorption cycle to heat the indoor unit for air conditioning. The present invention relates to an absorption cooling / heating machine that supplies cooling water to an exchanger and circulates cooling water between a absorber and a cooling tower fan by a cooling water pump for exhaust heat.

[0002]

2. Description of the Related Art In an absorption-type air conditioner using an absorption cycle, during cooling operation, a regenerator separates a refrigerant vapor from a low-concentration absorbent that has boiled due to heating of a gas burner, and the separated refrigerant vapor is cooled by a condenser. It is made into a refrigerant liquid and supplied to the evaporator. The absorbing liquid in which the refrigerant vapor is separated into a high concentration by the regenerator is sent to the absorber. The refrigerant liquid takes heat from its own evaporation to form a cooling source, cools cold / hot water circulating in the hot / cold water pipe, and circulates the cold / hot water to the air conditioning heat exchanger of the indoor unit to cool the room. Further, the absorbing liquid absorbs the refrigerant vapor from the evaporator in the absorber, and in order to discharge the heat generated at this time to the outside, the heat from the absorber is given to the cooling water by heat exchange, and the cooling tower fan is used. The cooling water is circulated and discharged to the cooling tower.

Further, during heating operation, a cooling / heating switching valve in the absorbing liquid flow path which connects the regenerator and the evaporator is opened to supply the absorbing liquid heated by the gas burner into the evaporator. As a result, the hot and cold water passing through the hot and cold water pipe in the evaporator is heated and circulated to the indoor terminals such as the indoor unit and the floor heating panel.

[0004]

When the water supply temperature is originally low, and when the water at the time of the change of seasons in spring and autumn or well water is used as the supply water, the supply temperature of the cooling water is lowered.
If the feed water temperature is low during the cooling operation, particularly at the start of the cooling operation, the temperature of the cooling water circulating between the absorber and the cooling tower by the cooling water pump decreases. Therefore, when the cooling tower fan is operated, the cooling water is further cooled and circulates at a temperature lower than the set temperature (for example, 30.5 ° C.).

If the cooling operation is started in this state, the temperature of the refrigerant supplied into the evaporator may drop extremely, and the refrigerant may freeze (hereinafter, "refrigerant freezing" is substantially the same as "freezing" of the evaporator). Used in). In this case, it is necessary to stop the cooling operation on the way as an evaporator low temperature abnormality, which causes a trouble such as interruption of the cooling operation. Further, the evaporation amount of the refrigerant also decreases as the load on the outdoor unit side sharply decreases due to the turning off of the thermosensor of the indoor terminal during the cooling operation. On the other hand, since the absorbing liquid maintains the original absorbing capacity, the absorber (ABS) is in a state of excessive absorbing capacity. As a result, the evaporator (refrigerant) is in a supercooled state, and the same trouble as at the start of the cooling operation occurs.

The present invention has been made in view of the above circumstances, and its purpose is to stop the cooling tower fan during the cooling operation, particularly when the temperature of the cooling water is lower than a predetermined temperature at the start of the cooling operation. To provide an absorption-type air conditioner that can prevent the cooling water from being excessively cooled to prevent the evaporator from freezing, avoid the evaporator low temperature abnormality, and start the cooling operation without trouble. It is in.

[0007]

(Aspect 1) In an absorption type air conditioner, a regenerator for heating an absorbing liquid containing a refrigerant by a heating means and separating a refrigerant vapor from the absorbing liquid,
A condenser that cools and condenses the refrigerant vapor separated by the regenerator, an evaporator that evaporates the refrigerant liquid generated by the condenser under low pressure, and an absorbing liquid in which the refrigerant vapor is separated by the regenerator. Cooling having an absorber that absorbs the refrigerant vapor evaporated by the evaporator, a cooling water pump that is connected to the absorber by a cooling water circulation path, circulates cooling water in the absorber, and a cooling tower fan that cools the cooling water An absorption cycle having a column, an absorption liquid pump for returning the absorption liquid from the absorber to the regenerator, and a heating absorption liquid flow having a cooling / heating switching valve and connecting the regenerator and the evaporator. And the cooling / heating switching valve is closed, the evaporator is used as a cooling source by the operation of the absorption cycle, and when the cooling / heating switching valve is opened, the absorption liquid heated by the regenerator is used as the heating absorption liquid. An absorption-type heat source device that supplies a heat source by supplying it to the evaporator through a passage, and cold / hot water heated or cooled by the heat exchange pipe of the evaporator is opened / closed from the heat exchange pipe by a cold / hot water pump. And a hot / cold water circulation circuit that circulates to the indoor terminal via the air conditioner, and detects the temperature of the cooling water circulating in the cooling water circulation path during the cooling operation by the temperature detecting means, and when the detected temperature is lower than a predetermined temperature. The cooling tower fan of the cooling tower is stopped.

(Claim 2) When the temperature of the cooling water detected by the temperature detecting means is equal to or higher than a predetermined temperature, the operation of the cooling tower fan is restarted.

(Claim 3) The temperature detecting means is a cooling water thermistor provided in the cooling water circulation path.

[0010]

(Advantages and Effects of the Invention) (Claim 1) During the cooling operation, particularly at the start of the cooling operation, the temperature detecting means detects the temperature of the cooling water in the cooling water circulation passage. When the detected cooling water temperature is lower than the predetermined temperature, the cooling tower fan is stopped.

As described above, when the cooling water has a temperature lower than the predetermined temperature, the cooling tower fan stops. As a result, the absorber does not have excessive absorption capacity, and excessive cooling of the evaporator can be suppressed. Therefore, it is possible to prevent the refrigerant temperature from excessively decreasing, prevent the evaporator from freezing, and avoid the evaporator low temperature abnormality.

Therefore, before the start of the cooling operation, the cooling operation can be started without any trouble, and during the cooling operation, the cooling operation can be continued without interruption.

(Claim 2) When the temperature of the cooling water exceeds a predetermined temperature, the operation of the cooling tower fan is restarted. Therefore, the circulation of the absorbing liquid is restored, and the absorbing liquid can be diluted.

(Claim 3) A cooling water thermistor is used as the temperature detecting means. Therefore, it is possible to obtain the temperature detecting means that is relatively durable and easily available.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an absorption type air conditioner and heater controlled by a control device 2A, which includes an outdoor unit 1A and a plurality of indoor units RU as indoor terminals. This outdoor unit 1A
Is composed of a heat source unit main body (absorption type heat source unit) 1B and a cooling tower CT including a cooling tower fan S and a water sprinkler Ds.

The heat source unit main body 1B of the outdoor unit 1A is mainly made of stainless steel, and forms an absorption cycle by using a refrigerant and an aqueous solution of lithium bromide as an absorbing liquid.

Reference numeral B is a gas burner as a heating means, and the gas fuel from the gas source Gs is sent to the gas burner B by the combustion fan F via the gas source electromagnetic valve 1a and the proportional valve 1b and ignited by the ignition plug 1d. When a flame is formed in the gas burner B by ignition, the output from the frame rod 1e is sent to the control device 2A.

1 is a high temperature regenerator, 2 is a low temperature regenerator,
Reference numeral 3 is an absorber, 4 is an evaporator, and 5 is a condenser. The absorbing liquid contains an inhibitor that suppresses corrosion of lithium bromide on stainless steel.

In the high temperature regenerator 1, the low-concentration absorption liquid supplied to the inside of the heating tank 11 is heated by the gas burner B, and is formed between the medium-concentration absorption liquid separation cylinder 12 and the absorption liquid partition container 13. When the absorption liquid after heating the solid absorption liquid ascending flow path 14 rises, water as a refrigerant in the low-concentration absorption liquid evaporates and separates as a refrigerant vapor (water vapor). The medium-concentration absorption liquid concentrated by the evaporation of the refrigerant vapor is redirected inward by the absorption liquid return plate 15, and the absorption liquid partition container 13
Returned inside.

The medium-concentration absorption liquid in which the refrigerant has been separated to have a high concentration is supplied to the low temperature regenerator 2 through the medium-concentration absorption liquid flow path L1 provided on the side of the absorption liquid partition container 13. The separated refrigerant vapor is recovered by the refrigerant absorption tank 10 and supplied to the condenser case 50 via the refrigerant flow path L5.
In addition, an inlet of a heating absorbing liquid channel L4 for supplying the absorbing liquid heated during the heating operation into the evaporator 4 is opened at the bottom of the absorbing liquid partition container 13.

Inside the lower part of the refrigerant absorption tank 10, a refrigerant partition cylinder 17 is joined to the outer surface of the medium-concentration absorbent separation cylinder 12 to form a heat insulating gap 17 a between the refrigerant partition cylinder 17 and the middle-concentration absorbent separation cylinder 12. is doing. Therefore, the heat in the medium-concentration absorbent separation column 12 is cut off, and the refrigerant in the refrigerant absorption tank 10 is not heated by the high-temperature absorbent in the absorbent rising passage 14. The outside of the refrigerant partition cylinder 17 in the refrigerant absorption tank 10 is a refrigerant storage section 10a for storing the separated liquid refrigerant, and the refrigerant stored in the refrigerant storage section 10a is in the condenser case via the refrigerant flow path L5. 50.

In the low-temperature regenerator 2, the medium-concentration absorbing liquid supplied through the medium-concentration absorbing liquid flow path L1 passing through the heat exchanger H on the way flows in from the ceiling of the low-temperature regenerator case 20, and enters the refrigerant absorption tank. It is reheated using the outer wall of 10 as a heat source, and is separated into a refrigerant vapor and a high-concentration absorbing liquid by the gas-liquid separation unit 22. The refrigerant vapor is the refrigerant vapor outlet 21 and the communication gap 5A.
Is supplied into the condenser case 50 from the
It is stored in the high-concentration absorbent receiving part 23 and supplied to the absorber 3 via the high-concentration absorbent flow path L2.

An orifice (not shown) for restricting the flow rate of the medium-concentration absorption liquid flowing from the absorption-liquid partition container 13 to the low-temperature regenerator 2 is provided in the medium-concentration absorption liquid flow path L1. The medium-concentration absorption liquid is supplied into the regenerator 2 due to the pressure difference between the medium-concentration absorption liquid separation cylinder 12. For this reason,
The internal pressure of the low temperature regenerator case 20 is about 70 mmHg, and the internal pressure of the medium concentration absorbent separation column 12 is about 700 mmHg.

In the absorber 3, a copper tube is wound in a vertical cylindrical shape inside an evaporation / absorption case 30, and has an absorption coil 31 wound in a coil as an absorption tube through which cooling water flows. (In FIG. 1, for simplification, it is described in a meandering shape like the evaporation coil 41 described later). The high-concentration absorption liquid supplied from the high-concentration absorption liquid receiving portion 23 of the low-temperature regenerator 2 flows into the upper end of the absorption coil 31 through the high-concentration absorption liquid channel L2 due to the pressure difference, and the high-concentration absorption liquid is supplied. It is sprayed by the spraying tool 32.

The high-concentration absorption liquid thus dispersed adheres to the surface of the absorption coil 31 in a thin film form, flows down by the action of gravity, absorbs water vapor, and becomes a low-concentration absorption liquid. When absorbing this water vapor, the surface of the absorption coil 31 generates heat,
It is cooled by the cooling water circulating in the absorption coil 31.
The water vapor absorbed by the high-concentration absorbent is generated as a refrigerant vapor in the evaporator 4 described later.

The low-concentration absorption liquid in the absorber 3 is heated by the operation of the absorption liquid pump P1 from the bottom 33 through the heat exchanger H and the low-concentration absorption liquid passage L3 in which the absorption liquid pump P1 is provided. Return to inside. Further, in the absorption coil 31, the cooling water cooled through the water sprinkler Ds of the cooling tower CT during the cooling operation circulates in the cooling coil 51 of the condenser 5.

The bottom portion 3 of the evaporation / absorption case 30 of the absorber 3
3 is connected to an ejector 65 as a gas extraction unit. The ejector 65 is provided to extract the non-condensable gas (hydrogen gas) generated in the absorption cycle. This guides the refrigerant vapor and the non-condensable gas in the absorber 3 from the suction conduit 67 to the gas-liquid separation pipe 66 by the ejector effect, separates the non-condensable gas from the absorption liquid, and the non-condensable gas storage section 68. Store in.

The evaporator 4 is provided on the outer circumference of a vertical cylindrical cylindrical partition plate 40 provided with a large number of communication ports (not shown) provided on the outer circumference of the absorption coil 31 in the evaporation / absorption case 30, and for cooling and heating the inside. A vertical cylindrical evaporation coil 41 made of a copper tube through which cold and hot water flows is disposed, and a refrigerant liquid spraying tool 42 is attached above it. The bottom 43 of the evaporator 4 communicates with the bottom of the absorbent partition 13 in the medium-concentration absorbent separating column 12 through a heating absorbent flow path L4 having an electromagnetic cooling / heating switching valve 6.

During the cooling operation, when the refrigerant liquid (water) is made to flow down on the evaporation coil 41 by the refrigerant liquid spraying tool 42, the flowing-down refrigerant liquid wets the surface of the evaporation coil 41 due to the surface tension to form a film, and the gravity Evaporation / absorption case 3 that has a low pressure (for example, 6.5 mmHg) while descending under action
In 0, the heat of vaporization is taken from the evaporation coil 41 to evaporate, and the cold hot water for air conditioning flowing in the evaporation coil 41 is cooled.

In the condenser case 50 accommodating the condenser 5, a dish-shaped refrigerant liquid receiver for receiving the refrigerant liquid in which the refrigerant vapor is cooled and liquefied by the cooling coil 51 at a position apart from the bottom of the condenser case 50. A section 52 is provided. The refrigerant liquid receiving portion 52 is located above the refrigerant liquid sprinkler 42 of the evaporator 4, and connects the refrigerant liquid supply path L6 to the refrigerant cooler 48 that cools the refrigerant liquid by self-cooling of the supplied refrigerant liquid. Is provided.

The condenser 5 communicates with the refrigerant reservoir 10a of the refrigerant absorption tank 10 through a refrigerant flow path L5 provided with an orifice (not shown) for limiting the refrigerant flow rate, and also with the refrigerant vapor outlet 21 and the communication. It also communicates with the low temperature regenerator 2 through the gap 5A. The refrigerant is supplied to the condenser 5 due to a pressure difference (about 70 mmHg in the condenser case 50). The refrigerant vapor supplied into the condenser case 50 during the cooling operation is cooled and liquefied by the cooling coil 51, and is supplied from the refrigerant liquid receiving portion 52 to the refrigerant cooler 48 via the refrigerant liquid supply passage L6.

The refrigerant liquid overflowing from the refrigerant liquid receiving portion 52 is
The concentration of the absorption liquid stored in the refrigerant liquid storage portion 54 formed by the inner bottom portion of the condenser case 50 and circulated in the absorption cycle during the cooling operation is maintained substantially high in order to ensure the cooling performance. The refrigerant liquid reservoir 54 and the refrigerant cooler 48 communicate with each other through a refrigerant liquid flow path L7 having the refrigerant valve 7, and when there is a risk of freezing of the refrigerant liquid, the refrigerant valve 7 is opened to control the refrigerant. The liquid is supplied to the evaporator 4, and freezing is prevented by increasing the vapor pressure in the evaporator 4. The refrigerant valve 7 is also opened at the start of the heating operation, all the refrigerant liquid stored in the refrigerant liquid storage portion 54 at the time of the cooling operation is supplied to the evaporator 4, and the concentration of the absorbing liquid circulated by heating during the heating operation. Is kept low to suppress the occurrence of crystallization.

During the cooling operation, the absorption liquid is the high temperature regenerator 1 → the medium concentration absorption liquid flow path L1 → the high concentration absorption liquid flow path L2 → the high concentration absorption liquid sprayer 32 → the absorber 3 → the absorption liquid pump P1 →
The low-concentration absorbent flow path L3 is circulated in the order of the high temperature regenerator 1.
Further, the refrigerant is the high temperature regenerator 1 (refrigerant vapor) → refrigerant flow path L5.
(Refrigerant vapor) or low temperature regenerator 2 (refrigerant vapor) → condenser 5 (refrigerant liquid) → refrigerant liquid supply path L6 (refrigerant liquid) or refrigerant liquid flow path L7 (refrigerant liquid) → refrigerant cooler 48 → refrigerant liquid spraying Tool 42 (refrigerant liquid) → evaporator 4 (refrigerant vapor) → absorber 3 (absorption liquid) → absorption liquid pump P1 → low-concentration absorption liquid flow path L3 → high temperature regenerator 1 in this order.

The absorption coil 31 of the absorber 3 that exchanges heat with the absorbing liquid and the cooling coil 51 of the condenser 5 are connected to form a continuous coil. This continuous coil has a cooling water flow path 3
4 is connected to the cooling tower CT to form a cooling water circulation path. In this cooling water circulation path, the absorption coil 31
In the cooling water flow path 34 existing between the inlet of the cooling water and the cooling tower CT, a cooling water thermistor (temperature detecting means) Tw for detecting the temperature of the cooling water and a cooling water pump P2 for feeding the cooling water into the continuous coil are provided. Has been. By the operation of this cooling water pump P2, the cooling water passing through the continuous coil is
The absorption coil 31 removes the absorbed heat, and the cooling coil 51 obtains the condensation heat to reach a relatively high temperature and is supplied to the cooling tower CT having the cooling tower fan S.

During the cooling operation, the cooling water pump P
By the operation of 2, the cooling water in the cooling tower CT is cooled by the cooling tower fan S.
While being promoted to evaporate by the air blow, the water is circulated in the order of sprinkler Ds → cooling tower CT → cooling water pump P2 → absorption coil 31 → cooling coil 51 → sprinker Ds → cooling tower CT. In this cooling tower CT, the falling cooling water is partially evaporated into the atmosphere. Therefore, the cooling water releases heat into the atmosphere to form a low temperature exhaust heat cycle.

Further, the outdoor unit 1A is provided with a cistern 69 for storing water, and the electrodes 70 and 71 allow the water supply passage 73 to be provided.
The water level of the feed water flowing into the water feed valve 72 is detected. The amount of water supplied is determined based on the detected water level, and the water supply to the cistern 69 is interrupted (on / off).

The outlet of the evaporation coil 41 of the evaporator 4 is connected to the cold / hot water outgoing path 60, and the inlet of the evaporation coil 41 is connected to the cold / hot water return path 61 via the cold / hot water pump P3 and the cistern 69. ing. Cold / hot water outgoing route 60
Is connected to each indoor unit RU as shown in FIG.
In each indoor unit RU, only the open / close valve Vt for cold / hot water of the indoor unit RU whose operation is instructed by the operation signal of the remote controller (not shown) for the indoor unit RU is driven to open. The open / close valve Vt may be provided in the cold / hot water flow path 47 on the side where cold / hot water flows into the indoor unit RU, but the open / close valve Vt may be incorporated in the indoor unit RU as a motor valve. Further, the opening / closing valve Vt provided in the cold / hot water flow path 47 and the indoor unit RU
You may arrange so that the on-off valve Vt built in may be mixed.

As for the indoor unit RU, the cold / hot water having a low temperature in the evaporation coil 41 is the outlet of the evaporation coil 41 → the cold / hot water outgoing path 60 → the upstream cold / hot water flow path 47 → the indoor units RU → Cold / hot water flow path 47 on the downstream side → cold / hot water return path 6
1-Cisturn 69-Cold and hot water pump P3-Evaporation coil
Circulate in the order of 1.

The heating absorbing liquid flow path L4 and the cooling / heating switching valve 6 are provided for heating. During the heating operation, the cooling / heating switching valve 6 is opened and the absorbing liquid pump P1 is operated. As a result, the high-temperature medium-concentration absorbing liquid in the absorbing-liquid partition container 13 in the medium-concentrating absorbing liquid separating cylinder 12 flows into the evaporator 4, and the evaporation coil 41 is heated by the high-temperature vapor (refrigerant vapor) of the medium-concentrated absorbing liquid. The cold and warm water inside is heated. The heated cold / hot water in the evaporation coil 41 is supplied from the cold / hot water flow path 47 to each indoor unit RU by the operation of the cold / hot water pump P3, and serves as a heat source for heating. The medium-concentration absorption liquid in the evaporator 4 enters the absorber 3 side from the communication port of the partition plate 40, passes through the low-concentration absorption liquid flow path L3, and returns to the heating tank 11 by the absorption liquid pump P1.

In the absorption type air conditioner of this embodiment, the absorption liquid pump P for circulating the absorption liquid in the absorption cycle is used.
1 and the cold / hot water pump P3 for circulating the cold / hot water cooled or heated by the evaporation coil 41 to the indoor unit RU through the cold / hot water passage 47 are individually driven by different motors.

Next, the control operation of the control device 2A for controlling the absorption type air conditioner will be described. The control device 2A is
The combustion control of the gas burner B, the drive control of the absorption liquid pump P1, the cooling water pump P2, and the hot / cold water pump P3, the control of the cooling water pump P2, the rotation control of the cooling tower fan S of the cooling tower CT, the absorption cycle are provided. The cooling and heating switching valve 6 and the refrigerant valve 7 are controlled to control the cooling operation and the heating operation of the absorption type air conditioner, and the cooling tower fan S is operated by receiving an output from the cooling water thermistor Tw as described later. Control.

[Heating operation] In the heating operation, the cooling / heating switching valve 6 is opened in response to the user's instruction to start the heating operation of the remote controller existing in the room where the indoor unit RU is installed, and the absorption liquid pump P1 and the cooling temperature are controlled. The operation of the motor that drives the water pump P3 is started, and the combustion of the gas burner B is performed. The absorption type air conditioner is configured to be able to supply cold / hot water from the outdoor unit 1A to the floor heating panel 30A via the opening / closing valve Vp. Therefore, in the control device 2A, whether or not the floor heating panel 30A is installed is determined based on the presence or absence of an operation signal from a remote controller (not shown) separately provided in the floor heating panel 30A to perform control. To do. The on-off valve Vp is provided as a thermal valve in the cold / hot water flow path 47 on the side where cold / hot water flows into the floor heating panel 30A.

[Cooling operation] In the cooling operation, the cooling / heating switching valve 6 is closed in response to the user's instruction to start the cooling operation of the remote controller existing in the room where the indoor unit RU is installed, and the absorption liquid is activated by the operation of the motor. The driving of the pump P1 and the cold / hot water pump P3 is started, and the combustion of the gas burner B is performed.

The control of the cooling tower fan S during the cooling operation, particularly at the start of the cooling operation, will be described with reference to the flowchart shown in FIG. When starting the cooling operation, first, in step S1, it is determined whether or not there is an operation instruction for the cooling tower fan S. When this operation instruction is given, step S is performed based on the output from the cooling water thermistor Tw of the cooling water flow path 34.
In step 2, it is determined whether the temperature of the cooling water is 25 ° C. or higher. If there is no operation instruction for the cooling tower fan S in step S1, the process returns to step S1. The temperature of the cooling water is 25 ℃
If it does not exceed, the process proceeds to step S3. In this step S3, the temperature of the cooling water does not exceed 25 ° C
It is repeatedly determined whether or not the temperature has risen to the above temperature.

When it is determined in step S2 that the temperature of the cooling water is 25 ° C. or higher, the cooling tower fan S is energized and the operation of the cooling tower fan S is started in step S4. At this time, when the operation of the cooling tower fan S is started, the rotation instruction value of the cooling tower fan S is proportionally controlled so that the cooling water reaches the set temperature of 30.5 ° C.

With the control operation of the cooling tower fan S, it is constantly detected in step S5 whether or not the temperature of the cooling water is 25 ° C. or higher. When the temperature of the cooling water is lower than 25 ° C., the cooling tower fan S is cut off and the operation of the cooling tower fan S is stopped in step S6. If it is determined in step S7 that the temperature of the cooling water is 28 ° C. or higher during this operation stop, the cooling tower fan S is re-energized and the operation of the cooling tower fan S is restarted in step S8.

In step S8, the rotation instruction value of the cooling tower fan S is proportionally controlled so that the cooling water reaches the set temperature of 30.5 ° C. as in the case of step S4. In step S8 or step S4 in which the proportional control of the cooling tower fan S is performed, the process proceeds to step S9, and when an instruction to stop the operation of the cooling tower fan S is received, the cooling tower fan S is operated by disconnection of power in step S10. Stop. Step S9
If there is no instruction to stop the cooling tower fan S, the process proceeds to step S4 to proportionally control the rotation instruction value of the cooling tower fan S. When it is determined in step S3 that the temperature of the cooling water is 28 ° C. or higher, the process proceeds to step S4 and the same process as described above (steps S4 to S10) is performed.

As shown in the flow chart, as long as an operation instruction is issued to the cooling tower fan S, as described above, the cooling tower fan S is turned on and off in accordance with the temperature of the cooling water to turn off the cooling tower. The operation of the fan S is controlled.

Thus, the cooling tower fan S is stopped when the temperature of the cooling water is lower than 25.degree. Cooling water temperature is 2
When the temperature rises to 8 ° C. or higher, the operation of the cooling tower fan S is restarted.
When the temperature of the cooling water is 25 ° C or higher, or when the temperature is 28 ° C or higher after the operation is stopped, the rotation instruction value of the cooling tower fan S is proportionally controlled so that the cooling water reaches the set temperature of 30.5 ° C. .

Therefore, the cooling water is maintained at the preset temperature of 30.5 ° C. by the proportional control of the cooling tower fan S. As a result, the amount of cooling for the evaporator 4 is appropriately maintained, the refrigerant temperature is not extremely lowered, the evaporator 4 is prevented from freezing, and the evaporator low temperature abnormality can be avoided. As a result, before the cooling operation, the cooling operation can be started without any trouble, and during the cooling operation, the cooling operation can be continued without interruption.

When the thermosensor of the indoor unit RU is turned off during the cooling operation, the load on the outdoor unit 1A is sharply reduced. Along with this, the evaporation amount of the refrigerant also decreases, but since the absorbing liquid maintains the original absorbing capacity, the absorber 3
Indicates a tendency of excessive absorption capacity. In this case, the operation of the cooling tower fan S is stopped, so that the absorber 3 does not have an excessive absorption capacity. Therefore, the cooling water does not receive excessive cooling, the evaporator low temperature abnormality can be avoided, and the cooling operation can be continued without interruption.

The operation of the cooling tower fan S is determined 25
The temperature of the cooling water of ℃ or more or 28 ℃ or more and the set temperature of 30.5 ℃ is an example, and these respective temperatures can be variously changed according to the installation environment and the use condition.

In the above embodiment, separate motors are used to drive the absorption liquid pump P1 and the cold / hot water pump P3 individually, but both the absorption liquid pump P1 and the cold / hot water pump P3 are driven by a single motor. A tandem pump driven at the same rotation speed may be used. Further, the cooling water thermistor Tw is
Both positive temperature characteristics and negative temperature characteristics may be used. Further, not only the cooling water thermistor Tw but also a bimetal or the like may be used,
In short, any temperature detecting means capable of detecting the temperature of the cooling water and controlling the disconnection of the cooling tower fan S can be used.

Further, in the absorption type cooling / heating machine according to the present invention, 2
Although the description has been given using the utility formula, it may be a single-effect formula or a multiple-effect formula. Further, as the heating source, kerosene, petroleum, an electric heater or the like may be used instead of the gas fuel.

Further, in practicing the present invention, the number of indoor units RU is not limited to three, and a desired number can be set, and a systern 69 for water storage and a floor heating panel 30A can be provided as needed. Various changes can be made without departing from the scope of the present invention.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an absorption type air conditioner / heater according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of an indoor unit, an outdoor unit, and a floor heating panel.

FIG. 3 is a flowchart relating to control of a cooling tower fan.

[Explanation of symbols]

1 High temperature regenerator 2 low temperature regenerator 3 absorber 4 evaporator 5 condenser 6 cooling / heating switching valve 34 Cooling water flow path (cooling water circulation path) 41 Evaporation coil (heat exchange pipe) 47 Cold / hot water flow path (cold / hot water circulation circuit) 1A outdoor unit 1B heat source unit (absorption type heat source unit) 2A control device RU indoor unit (indoor terminal) B gas burner (heating means) CT cooling tower S cooling tower fan L4 Absorbing liquid flow path for heating P1 absorption pump P2 cooling water pump P3 cold / hot water pump Tw Cooling water thermistor (temperature detection means) Vp, Vt open / close valve

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Naoyu Sugimoto             Rinnai 2-26, Fukuzumi-cho, Nakagawa-ku, Nagoya-shi             Within the corporation (72) Inventor Kaoru Kawamoto             4-1-2 Hirano-cho, Chuo-ku, Osaka City, Osaka             Gas Co., Ltd. F term (reference) 3L093 AA05 BB11 BB22 CC03 DD09                       EE14 GG02 HH04 JJ08 KK01                       LL03

Claims (3)

[Claims] 1. A regenerator for heating an absorbing liquid containing a refrigerant by a heating means to separate the refrigerant vapor from the absorbing liquid, a condenser for cooling and condensing the refrigerant vapor separated by the regenerator, and this condenser. An evaporator for evaporating the refrigerant liquid generated by the refrigerant under low pressure; an absorber for absorbing the refrigerant vapor evaporated by the evaporator in the absorbing liquid in which the refrigerant vapor is separated by the regenerator; and the absorber and the cooling water circulation path. And a cooling tower having a cooling water pump for circulating cooling water in the absorber and a cooling tower fan for cooling the cooling water, and an absorption liquid pump for returning the absorption liquid from the absorber to the regenerator. An absorption cycle having: a heating absorption liquid flow path having a cooling / heating switching valve that connects the regenerator and the evaporator; and, when the cooling / heating switching valve is closed, the evaporation cycle is performed by the operation of the absorption cycle. As a cooling source, and when the cooling / heating switching valve is opened, an absorption heat source device that supplies the absorption liquid heated by the regenerator to the evaporator via the heating absorption liquid flow path to serve as a heating source. A hot / cold water circulation circuit that circulates cold / hot water heated or cooled by the heat exchange pipe of the evaporator from the heat exchange pipe to an indoor terminal device via an on-off valve by a cold / hot water pump, and during the cooling operation, Absorption cooling and heating, characterized in that the temperature of the cooling water circulating in the cooling water circulation path is detected by a temperature detecting means, and when the detected temperature is lower than a predetermined temperature, the cooling tower fan of the cooling tower is stopped. Machine. 2. The absorption type cooling and heating machine according to claim 1, wherein when the temperature of the cooling water detected by the temperature detecting means is equal to or higher than a predetermined temperature, the operation of the cooling tower fan is restarted. 3. The absorption cooling and heating machine according to claim 1, wherein the temperature detecting means is a cooling water thermistor provided in the cooling water circulation path.