JPH1038405A - Absorption cold/warm water machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need of waiting for a predetermined time when the operation is changed over from a heating operation to a cooling operation by detecting pressure in a machine or temperature of a solution in the machine, and changing over the operation to the cooling operation when the pressure or the temperature reaches a set value. SOLUTION: A solution in a high temperature regenerator 10 is heated in a heating apparatus 12 in heating operation, and produced high temperature refrigerant vapor is cooled and liquefied with warm water 17 in a tube passing through an evaporator 1 to provide heat to the water in the tube for heating. There is provided a sensor 18 for detecting solution temperature in an absorber 5 or the high temperature regenerator 10 or a low temperature regenerator 11 or there is provided a sensor 19 on a vapor piping 16 through which vapor produced from the high temperature regenerator 10 passes for detecting pressure. For achieving cooling operation a cooling water pump 2 is operated to supply the cooling water to the absorber 5 and a condenser 13. Provided herein it is detected by the sensor 18 or the sensor 19 that the solution temperature in the machine or pressure in the high temperature regenerator 10 is high, there is performed control where the operation waits until the solution temperature or pressure reaches predetermined temperature or pressure or lower.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an absorption chiller / heater.

[0002]

2. Description of the Related Art FIG. 2 shows switching of a conventional absorption chiller / heater from a heating operation to a cooling operation. In the absorption refrigerator including the seven heat exchangers of the evaporator 1, the absorber 5, the condenser 13, the high-temperature regenerator 10, the low-temperature regenerator 11, the high-temperature heat exchanger 9, and the low-temperature heat exchanger 8, the heating operation is started. To switch to cooling operation, the machine had to be left for 2-3 hours. In the heating operation, the steam pipe gate valve 21 is opened. The solution in the machine is circulated by the solution pump 7 and the high-temperature regenerator 1
0, the temperature of the solution inside the low-temperature regenerator 11 and the absorber 5 is 60
C. to about 80.degree. Immediately after the heating operation is stopped, the steam pipe gate valve 21 is closed to perform the cooling operation, and the cooling water 3 from the cooling tower 20 (about the same as the outside air temperature, about 15 to 25 ° C.)
When water is passed through the absorber 5 and the condenser 13, the pressure inside the absorber 5 and the condenser 13 suddenly drops. On the other hand, since the high-temperature regenerator 10 is immediately after the heating operation, the internal pressure is high. Since the high-temperature regenerator 10 and the absorber 5 are connected to each other by a solution pipe, when the cooling water 3 is passed in this way immediately after heating, the solution is transferred from the high-temperature regenerator 10 to the absorber 5 or the refrigerant vapor in the machine. May blow through the absorber 5. Since the solution in the absorber also boils violently, the baffle 6
And the solution is mixed into the adjacent evaporator 1. On the other hand, the evaporator 1 always requires high-purity water (refrigerant) during the cooling operation, and if particles of the solution flow into the evaporator 1 from the absorber 5, the evaporation performance is reduced and the refrigerating capacity is also reduced. The solution once mixed into the evaporator 1 is supplied from a blow pipe 15 for guiding the liquid refrigerant 4 in the evaporator 1 to the absorber 5 through a gate valve 14.
Is not discharged from the evaporator 1 unless the air is blown into the absorber 5 and is blown into the absorber 5, and is accumulated together with the liquid refrigerant 4. In order to prevent such a situation, a human operator confirms that the internal pressure of the high-temperature regenerator 10 does not switch to the cooling operation until the temperature of the solution in the apparatus is lowered, or manually starts the operation, or unconditionally uses a timer or the like for a predetermined time or more. It is common to leave it alone. Further, the steam pipe gate valve 21 is operated manually or automatically by a timer or the like using an electric valve or the like.

In Japanese Unexamined Patent Publication No. Hei 7-260282, when an operation command for heating to cooling is issued, when the temperature of the absorbent temperature detecting means is higher than the upper limit for judging the start of operation, the apparatus stands by in a stopped state, In the following cases, cooling operation is started.

[0004]

When switching from the heating operation to the cooling operation, waiting for a certain period of time with a timer is a pain for a user who wants to immediately perform the cooling operation. In a season in which heating is switched to cooling, the heating operation itself is unlikely to be a full load operation, and the load is low, that is, the temperature of the solution and the pressure in the machine are often low. In other words, the machine is controlled to wait by a timer until it is safe to switch from heating to cooling.

[0005]

According to the present invention, the pressure in the machine or the temperature of the solution in the machine is sensed, and when the set value is reached, control for switching from heating to cooling operation is performed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, switching from a heating operation to a cooling operation will be described. In the heating operation, the solution in the high-temperature regenerator 10 is heated by the heating device 12, and refrigerant vapor is generated. The high-temperature refrigerant vapor passes through the vapor pipe 16 and passes through the evaporator 1.
The liquid is cooled and liquefied by the warm water 17 in the tube penetrated into the tube, and at this time, heat is given to the water in the tube to provide heating. The liquefied liquid refrigerant is guided again from the evaporator 1 to the absorber 5, where it is mixed with the solution, and the solution is pumped by the solution pump 7 to the high temperature regenerator
Transported to Here, a sensor 18 for detecting the solution temperature of the absorber 5, the high-temperature regenerator 10 or the low-temperature regenerator 11 is provided. Alternatively, a sensor 19 for sensing pressure is installed in a steam pipe 16 through which steam generated from the high-temperature regenerator 10 passes.
In order to perform the cooling operation, the cooling water pump 2 is operated, and the cooling water is passed through the absorber 5 and the condenser 13. At this time, if the solution temperature inside the machine or the inside pressure of the high-temperature regenerator 10 is high, the solution is mixed into the liquid refrigerant 4 inside the evaporator 1 as described above, which hinders the cooling operation. Alternatively, control is performed to wait until the pressure becomes equal to or less than the pressure. For example, during heating operation,
Since the solution temperature inside the absorber 5, the high-temperature regenerator 10 and the low-temperature regenerator 11 is 60 ° C. to 80 ° C., if the solution temperature of the absorber 5 becomes 40 ° C. or less, the control is switched to the cooling operation. Since the boiling of the solution in the vessel 5 can be prevented, the cooling operation can be started without a concern that the solution particles are mixed into the evaporator 1. Here, control for detecting the internal pressure of the high-temperature regenerator 10 may be performed. For example, if the internal pressure of the high-temperature regenerator 10 is reduced to −600 mmHg or less, if the control for starting the cooling operation is performed, it is possible to prevent the steam from flowing from the high-temperature regenerator 10 to the absorber 5 and mix the solution into the evaporator 1. There is no need to worry about this, and stable cooling operation can be realized.

[0007]

According to the present invention, as a control for switching from heating to cooling, the temperature or pressure on the machine side is detected and controlled to wait until a certain condition or less is obtained. Absent. Also, the temperature of the refrigerator body or
Since the pressure is detected, the difference depending on the model and the environment can be canceled, so that it is possible to safely switch from heating to cooling. That is, when switching from heating to cooling, the user can arbitrarily switch without heating by a specialized maintenance person.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of switching from heating to cooling according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of conventional switching from heating to cooling.

[Description of Signs] 1 ... evaporator, 2 ... cooling water pump, 3 ... cooling water, 4 ... liquid refrigerant, 5 ... absorber, 6 ... baffle plate, 7 ... solution pump, 8 ... low temperature heat exchanger, 9 ... High temperature heat exchanger, 10 ... High temperature regenerator, 1
DESCRIPTION OF SYMBOLS 1 ... Low temperature regenerator, 12 ... Combustor, 13 ... Condenser, 14 ...
Gate valve, 15: blow pipe, 16: steam pipe, 17: hot water, 18: temperature sensor, 19: pressure sensor, 20: cooling tower, 21: steam pipe gate valve.

Claims (1)

[Claims] 1. An absorption chiller / heater including an evaporator, an absorber, a low-temperature regenerator, a high-temperature regenerator, and a heat exchanger, wherein a sensor for sensing pressure or temperature is provided, and when the heating operation is switched to the cooling operation, An absorption chiller / heater, which is automatically started when a pressure or temperature reaches a set value by a sensor.