JPS6033446A - Operation control of air-conditioning machine - Google Patents

Abstract

PURPOSE:To prevent wet compression of a compressor and improve the rise-up of room heating operation by a method wherein a solenoid opening and closing valve, provided between the delivery side and suction side of the compressor, is opened to regulate the circulating amount of heat medium and, thereafter, an indoor fan is operated. CONSTITUTION:The compressor 5, an indoor side heat exchanger 2, an outdoor side heat exchanger 13 and a heat medium heater 9 are connected in a loop to constitute a refrigerating cycle and, further, the solenoid opening and closing valve 8, communicating or interception the delivery side and the suction side of the compressor 5, is provided between the delivery and suction sides of the compressor 5. Upon the beginning of room heating operation, in which the circulating amount of heat medium becomes insufficient, the solenoid valve 8 is being closed and when the delivery pressure of the compressor has arrived at a predetermined pressure and the sufficient circulating amount of heat medium has been obtained, the solenoid valve 8 is opened to regulate the circulating amount of heat medium and, thereafter, an indoor fan 3 is operated, whereby the circulating amount of heat medium will never become excessive, the compressor 5 will never cause the wet compression during the room heating operation and the damage of the compressor 5 may be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat medium heating system that obtains heating capacity by conveying heat supplied from a fuel combustion device such as oil or gas or a heating source such as an electric heater to an indoor unit. The present invention relates to a method for controlling the operation of an air conditioner equipped with an air conditioner.

The structure of the conventional example and its problems The conventional example will be explained with reference to FIG. In the figure, reference numeral 1 denotes an indoor unit, which includes an indoor heat exchanger 2, a chamber 27, an indoor fan 3, and the like. 4 is an outdoor unit 1-, which includes a compressor 5, a heating/cooling switching valve 6, a two-way valve 7, a solenoid valve 8, a heating medium heating device 9, a first check valve 10, a second check valve 11, and a pressure reducer. 12, an outdoor heat exchanger 13 and an outdoor fan 14 used for cooling are provided. Note that solid arrows indicate the flow of heat medium during heating, and dashed arrows indicate the flow of refrigerant during cooling.

Next, the flow of the heat medium (refrigerant) having the above configuration will be explained.

First, during cooling, as is conventionally known, the cooled air discharged from the compressor 5 passes through the heating/cooling switching valve 6, radiates heat in the outdoor heat exchanger 13, and then passes through the pressure reducer 11 and the first non-return check valve. After passing through the valve 9, the air enters the indoor unit 1 and is evaporated in the indoor heat exchanger 2, exerting its cooling ability. Thereafter, the air returns to the outdoor unit 4 and is sucked into the compressor 5 via the heating/cooling switching valve 6, and thereafter this cycle is repeated to perform cooling operation.

Next, during heating, the heat medium discharged from the compressor 6 enters the indoor unit 1 via the heating/cooling switching valve 6, where it is radiated and condensed in the chamber 3 and the inner heat exchanger 2, thereby exerting its heating ability. It then enters the outdoor unit 4, passes through the two-way valve 7, is heated and evaporated in the heat medium heating device 9, and is sucked into the compressor 6. Here's the first one. The second check valve 10.11 is connected to the outdoor heat exchanger 13 used during cooling when the suction pressure of the compressor 5 increases during heating and the saturated humidity of the heating medium at that pressure becomes higher than the outside air. This prevents heat medium from accumulating in the tank.

By the way, since the heat medium is heated by the heat medium heating device 9 during heating, the evaporation pressure can be set higher than during cooling. However, for this reason, during cooling and heating, the heat medium (cold ts
) The amount of heat medium circulated varies greatly, so during heating, the suction side and the discharge side of the compressor 5 are connected through a solenoid valve 8 to reduce the amount of heat medium circulated. However, the compressor 5 has not been operated for a long time. When you are in a so-called sleep state,
If the amount of heat medium circulation is small and the solenoid valve 8 is opened at the start of heating operation to communicate the suction side and discharge side of the compressor 5, the heat medium heating device 9 will overheat and heating must be interrupted several times. However, the start-up will be delayed.

For this reason, the solenoid valve 8 is closed when heating operation starts.
The heat medium is flowed only through the main circuit to improve the startup, and when the pressure rises and the amount of heat medium circulation increases, the electromagnetic valve 8 is opened using a pressure switch or the like to adjust the amount of heat medium circulation.

By the way, in order to prevent cold air from blowing out, heating air conditioners often detect the pressure of the heating medium or the humidity in the pipes, and start operating the indoor blower when the set value reaches 0. There is.

Conventionally, the opening timing of the solenoid valve 8 that communicates the suction side and the discharge side of the compressor 5 is not related to the timing when the indoor fan 3 starts operating.
Sometimes it happened before and sometimes after the start of operation.

FIG. 3 shows the change in discharge pressure at the start of heating operation in the conventional example. In the figure, if the indoor fan 3 starts operating before the solenoid valve 8 opens at point A, when the indoor flow rate is low, the refrigerant pressure and piping flow rs will drop significantly due to heat exchange with the indoor air, and the pressure Alternatively, the piping flow rate increases and it takes time until the solenoid valve 8 opens. During this time, since the solenoid valve 8 is closed, the amount of heat medium circulated is excessive compared to the amount of heat added from the heat medium heating device 9, and the heat medium is sucked into the compressor 6 in a moist state, and from the point in time A, the heat medium is sucked into the compressor 6. During the time of
As shown in the figure, the discharge pressure fluctuates, and the compressor 5 has the disadvantage that it causes liquid compression and significantly shortens its life. It's a trench.
The heating cycle becomes unstable due to liquid compression, which slows down the increase in heat medium pressure, causing a vicious cycle in which the opening timing of the solenoid valve 8 is further delayed.

Purpose of the Invention The present invention solves the above-mentioned conventional drawbacks, and aims to prevent damage to the compressor at the start of heating operation of an air conditioner having a heat medium heater, and to improve start-up performance. It is something to do.

Structure of the Invention In order to achieve this object, the present invention configures a refrigeration cycle by connecting a compressor, an indoor heat exchanger, an outdoor heat exchanger, and a heat medium heater in an annular manner. An electromagnetic on-off valve is connected between the discharge side and the suction side to provide six-way communication or isolation between the two, and after opening the electromagnetic on-off valve, the indoor fan is operated.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Here, since the refrigeration cycle is the same as the conventional example, FIG. 1 will be used. Also, FIG. 2 is a control circuit diagram of a solenoid valve 80 that communicates the intake and discharge of the indoor fan 3 and compressor 5 in an air conditioner, and the same parts as in FIG. 1 are given the same numbers and explained. Omit. In FIG. 2, 16 is a pressure switch provided in the indoor unit 1, 16 is a pressure switch provided in the outdoor unit 4, and both of these are 2
It has two contacts H and L, and when the pressure increases, the contact piece moves to contact H.
It is designed to fall to the side. The pressure switch 16 is set so that the contact piece of the pressure switch 16 falls toward the contact H side at a pressure lower than the set pressure at which the contact piece falls toward the contact H side. 17
．． Coils 18, 19 and 20 close contacts 21, 22 and 23, 24, respectively, when energized.

In the configuration of 7 or more vegetables, the flow of the heat medium (refrigerant) is the same as in the conventional example, and will therefore be omitted. First, the compressor 6 and the heat medium heater 9
is operated and the pressure of the heating medium increases and the contact of the pressure switch 16 falls to the contact H side, the coil 19 is energized and the contact 2
3 is closed, and the coil /l/ 20 is energized and the contact 24
is closed, the solenoid valve 8 is opened, and the discharge side and suction side of the compressor 5 are communicated.

That is, when the pressure of the heat medium becomes negative and the amount of heat medium circulation increases, the electromagnetic valve 8 is opened to adjust the amount of heat medium circulation. In addition,
After the contact piece of the pressure switch 16 falls to the contact H side, the pressure decreases due to the action of the coil 19, and even if the pressure switch 16 falls to the contact side, the solenoid valve 8 continues to open.

FIG. 4 shows the fluctuation state of the discharge pressure in this embodiment.

That is, when the solenoid valve 8 is opened at the pressure A, the discharge pressure decreases once, but after receiving heat from the heating medium heating device 9, it begins to rise again.

When the pressure reaches the mouth, the contact piece of the pressure switch 16 falls to the contact H side, and the coils 17 and 18 are energized in order.
Indoor fan 3 operates. The pressure decreases due to heat exchange with the indoor air, but due to the action of the coil 17, the indoor fan 3 continues to operate even if the contact piece of the pressure switch 15 falls to the contact side. Here, the pressure at which the opposite piece of the pressure switch 16 falls towards the contact H side is set higher than the pressure at which the contact piece of the pressure switch 16 falls towards the contact H side. The vehicle will not start operating first.

In other words, at the start of heating operation when the heat medium circulation amount is insufficient, the solenoid valve 8 is closed, and when the discharge pressure reaches the pressure A and a sufficient heat medium circulation amount is obtained, the solenoid valve 8 is opened. Since the indoor fan 3 is operated after adjusting the circulation amount, the amount of heat medium circulation does not become excessive, and the compressor 6 is operated in a heating operation without causing wet compression, thereby preventing damage to the compressor 5. Moreover, since the heating cycle is easily stabilized, the start-up is good.

Note that in this embodiment, pressure switches 15 with different set pressures are used.
．． 16 was used, but the operation of the indoor fan 3 was started by detecting a rise in pipe temperature, and when the lightning 1 solenoid valve 8, which communicates the suction side and discharge side of the compressor 5 on page 9, is not open. The control may also prohibit the operation of the indoor fan 3. Alternatively, a control method may be used in which the indoor fan 3 is operated by a timer after the solenoid valve 8 that communicates the suction side and the discharge side of the compressor 6 is opened.

Effects of the Invention As is clear from the above embodiments, the present invention configures a refrigeration cycle by connecting a compressor, an indoor heat exchanger, an outdoor heat exchanger, and a heat medium heater in a ring, and An electromagnetic on-off valve is installed on the discharge side and suction side of the compressor to communicate or cut off the communication between the two, and after opening the electromagnetic on-off valve and adjusting the amount of heat medium circulation, the indoor fan is operated to perform wet compression in the compressor. This has the effect of preventing heating operation and improving the start-up of heating operation.

[Brief explanation of the drawing]

Fig. 1 is a refrigeration cycle diagram of an air conditioner equipped with a heat medium heater, Fig. 2 is an electric circuit diagram of an air conditioner implementing the operating method of the present invention, and Fig. 3 is a conventional air conditioner 1o7. - An explanatory diagram of changes in discharge pressure in the operation control method of a gas conditioner,
FIG. 4 is an explanatory diagram of changes in discharge pressure in the air conditioner operation control method of the present invention. 2... Indoor heat exchanger, 3... Indoor fan, 6... Compressor, 8... Solenoid valve,
9... Heat medium heating device, 13... Outdoor heat exchanger. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure -2 Figure 3 /'7 18 d /q z0

Claims (1)

[Claims] A compressor, an indoor heat exchanger, an outdoor heat exchanger, and a heat medium heating device are connected in a ring to form a refrigeration cycle, and the discharge side and suction side of the compressor are connected or disconnected. A method for controlling the operation of an air conditioner, which connects a solenoid valve to open the solenoid valve, and then operates an indoor fan after opening the solenoid valve.