FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)
"CONTROL DEVICE FOR AIR CONDITIONING SYSTEM, AIR
CONDITIONING SYSTEM, AND METHOD FOR DETERMINING
ANOMALY OF AIR CONDITIONING SYSTEM"
MITSUBISHI HEAVY INDUSTRIES, LTD. , of 16-5, Konan 2-
chome, Minato-ku, Tokyo 1088215, Japan
The following specification particularly describes the invention and the manner in which it is to
be performed.
DESCRIPTION
Title of the Invention
CONTROL DEVICE FOR AIR CONDITIONING SYSTEM, AIR
CONDITIONING SYSTEM, AND METHOD FOR DETERMINING ANOMALY OF
AIR CONDITIONING SYSTEM
Technical Field
[0001]
The present invention relates to a control device
for an air conditioning system, an air conditioning system,
and a method for determining an anomaly of an air
conditioning system.
Background Art
[0002]
Makers acquire operating data of an air conditioning
system through remote monitoring, and perform proposal for
energy saving to customers, determination of the presence
or absence of a need for maintenance, and the like, for
example, in related-art air conditioning systems, as part
of maintenance.
[0003]
In the related-art air conditioning systems that
control an outdoor unit and an indoor unit using different
control devices, respectively, the outdoor unit and the
- -1'
indoor unit are operated by different control programs.
Therefore, it is difficult to accurately ascertain an
operating state of an air conditioning system.
Thus, NPL 1 discloses an air-conditioning remote
monitoring system in which a local server installed within
a customer's building periodically transmits operating
data of an air conditioner to an air-conditioning remote
monitoring center server through the Internet, and the
operating data that the center server has received are
displayed on a monitoring screen of an air-conditioning
remote monitoring center. In this air-conditioning remote
monitoring system, main data (pressure value, refrigerant
temperature, the rotational speed of a fan, the operation
time of a compressor, the rotational speed of the
compressor, the number of times of starting and stopping
of the compressor, and the like) of the air conditioner
are transmitted at regular intervals to the center server.
[0004]
Then, in a case where an anomaly has occurred, a
malfunction site showing the anomaly is specified on the
basis of the operating data transmitted to the center
server, and a maker carries out a contact with the service
center and a request for repair.
Citation List
Non-Patent Literature
-r2'
[0005]
NPL 1: TOSHIBA REVIEW Vol. 60, No.6 (2005), Pages.52
to 55
Summary of Invention
Technical Problem
[0006]
However, in an area where external network
environment, such as the Internet, is insufficient, it is
difficult to install the air-conditioning remote
monitoring center server. Additionally, high costs are
required also for the installation of the air-conditioning
remote monitoring center server.
[0007]
Moreover, if the indoor unit and the outdoor unit
manufactured by different makers are used for the air
conditioning system, it is necessary to determine whether
or not machinery (also referred to as functional
components) installed in these units is operating
correctly as the air conditioning system. Unless this
determination is performed, the cause of an anomaly of the
air conditioning system cannot be made clear, and a maker
who has the responsibility for the anomaly cannot be
clarified.
[0008]
The invention has been made in view of such
circumstances, and an object thereof is to provide a
control device for an air conditioning system, an air
conditioning system, and a method for determining an
anomaly of an air conditioning system that can simply and
accurately ascertain an operating state of the air
conditioning system more.
Solution to Problem
[0009]
In order to solve the above problem, a control
device for an air conditioning system, an air conditioning
system, and a method for determining an anomaly of an air
conditioning system in the invention adopts the following
means.
[0010]
A control device for an air conditioning system
related to a first aspect of the invention is a control
device for an air conditioning system including one or a
plurality of outdoor units and one or a plurality of
indoor units. The control device includes an outdoor-unit
control part capable of communication with the outdoor
unit through a communication medium, the outdoor-unit
control part acquiring, through the communication medium,
information about machinery installed in the outdoor unit
and outputting a control command to the machinery
installed in the outdoor unit; an indoor-unit control part
- A' ' -
capable of communication with the indoor unit through the
communication medium, the indoor-unit control part
acquiring, through the communication medium, information
about machinery installed in the indoor unit and
outputting a control command to the machinery installed in
the indoor unit; storage means for storing an operating
state of the air conditioning system for each load state
of the air conditioning system; and anomaly determination
means for determining the presence or absence of an
anomaly in the machinery by comparing a present operating
state and a past operating state associated with an
equivalent load state.
[0011]
In the control device for an air conditioning system
related to this configuration, the outdoor-unit control
part that outputs the control command to the machinery
installed in the outdoor unit, and the indoor-unit control
part that outputs the control command to the machinery
installed in the indoor unit are virtually loaded. The
machinery installed in the outdoor unit or the indoor unit
is, for example, an expansion valve, a fan, and a four-way
valve.
That is, since the indoor-unit control part and the
outdoor-unit control part are present independently from
the indoor unit and the outdoor unit, the configurations
of the indoor unit and the outdoor unit are simplified.
Moreover, for example, like installation for only
communication and actuator functions of components, it is
not necessary to load advanced programs into the indoor
unit and the outdoor unit, and replacement of the indoor
unit and the outdoor unit can be easily performed. In
addition, as long as the indoor unit or the outdoor unit
satisfies specification, the indoor unit and the outdoor
unit manufactured by a maker different from that of the
control device may be adopted.
[0012]
Here, in the related-art air conditioning systems
that control the outdoor unit and the indoor unit using
the different control devices, respectively, the outdoor
unit and the indoor unit are operated by different control
programs. Therefore, it is difficult to accurately
ascertain the operating state including an anomaly of the
overall air conditioning system. For this reason, in the
related-art air conditioning systems, it is necessary to
collect and manage data, such as the operating state and
various state quantities of the air conditioning system,
using a server or the like for remote monitoring.
Moreover, if the indoor unit and the outdoor unit
manufactured by different makers are used for the air
conditioning system, it is necessary to determine whether
or not the machinery installed in these units is operating
correctly as the air conditioning system.
[0013]
Thus, in the control device of the air conditioning
system related to this configuration, the operating state
of the air conditioning system is stored for each load
state of the air conditioning system by the storage means.
The operating state of the air conditioning system is a
combination of operating points of respective pieces of
the machinery installed in the indoor unit or the outdoor
unit, and the state quantities (the temperature, pressure,
and the like of the refrigerant) of the air conditioning
system. The presence or absence of an anomaly in the
machinery is determined by the anomaly determination means
by comparing the present operating state with the past
operating state associated with the equivalent load state.
That is, the control device performs passive monitoring
control.
In addition, the equivalent load state means that
outdoor air temperature, the number of operating indoor
units, or the like is the same or is within an allowable
error range even if the number of operating indoor units
is different. Additionally, the past operating state may
be an own past operating state, for example, may be a past
operating state of another air conditioning system with
the same configuration of the machinery.
[0014]
Additionally, in the air conditioning system related
to this configuration, one control device controls the
indoor unit and the outdoor unit. Thus, the control
states of the respective pieces of machinery, the various
state quantities in the air conditioning system, and the
like can be managed by the control device. That is, in
this configuration, the operating state of the air
conditioning system can be ascertained simply and
accurately without using the server for remote monitoring
like the related-art air conditioning systems.
Additionally, in the air conditioning system related
to this configuration, even if the indoor unit and the
outdoor unit manufactured by different makers are used,
the presence or absence of an anomaly is determined by
associating the operating points and the state quantities
of these pieces of machinery with each other and by
comparing the present and past operating states with each
other. Thus, it is possible to accurately ascertain the
influence that the operation of the machinery has on the
air conditioning system.
[0015]
As described above, in this configuration, the
present and past operating states of the air conditioning
system in the equivalent load state are compared with each
other. Thus, a change in the operating state in a case
where an anomaly has occurred in the machinery becomes
clear. Therefore, in this configuration, it is possible
to more simply and accurately ascertain the operating
state of the air conditioning system.
[0016]
In the above first aspect, the anomaly determination
means may determine the presence or absence of an anomaly
in the machinery on the basis of predetermined state
quantities of the air conditioning system that fluctuate
more easily according to the operation of the machinery.
[0017]
According to this configuration, the presence or
absence of an anomaly in the machinery is determined on
the basis of the predetermined state quantities that
fluctuate more easily according to the operation of the
machinery. Thus, the operating state of the air
conditioning system can be determined earlier.
[0018]
In the above first aspect, the amount of a
refrigerant within the air conditioning system may be
calculated on the basis of a state quantity of the air
conditioning system.
[0019]
According to this configuration, the presence or
absence of leakage of the refrigerant can be detected, on
the basis of a time change in the flow rate of the
refrigerant.
[0020]
An air conditioning system related to a second
aspect of the invention includes one or a plurality of
outdoor units; one or a plurality of indoor units; and the
control device described in the above.
[0021]
A method for determining an anomaly of an air
conditioning system related to a third aspect of the
invention is a method for determining an anomaly of an air
conditioning system including one or a plurality of
outdoor units and one or a plurality of indoor units, an
outdoor-unit control part capable of communication with
the outdoor unit through a communication medium, the
outdoor-unit control part acquiring, through the
communication medium, information about machinery
installed in the outdoor unit and outputting a control
command to the machinery installed in the outdoor unit,
and an indoor-unit control part capable of communication
with the indoor unit through the communication medium, the
indoor-unit control part acquiring, through the
communication medium, information about machinery
installed in the indoor unit and outputting a control
command to the machinery installed in the indoor unit.
The method includes storing an operating state of the air
conditioning system for each load state of the air
conditioning system; and determining the presence or
absence of an anomaly in the machinery by comparing a
present operating state and a past operating state
associated with an equivalent load state.
Advantageous Effects of Invention
[0022]
According to the invention, an excellent effect that
the operating state of the air conditioning system can be
ascertained more simply and accurately is exhibited.
Brief Description of Drawings
[0023]
Fig. 1 is a view illustrating a refrigerant system
of an air conditioning system related to an embodiment of
the invention.
Fig. 2 is an electrical configuration diagram of the
air conditioning system related to the embodiment of the
invention.
Fig. 3 is a functional block diagram of an anomaly
determination control part related to the embodiment of
the invention.
Fig. 4 is a flowchart illustrating a flow of anomaly
determination processing related to the embodiment of the
invention.
Fig. 5 is a flowchart illustrating a flow of anomaly
determination related to the embodiment of the invention.
Fig. 6 is a flowchart illustrating a flow of
refrigerant amount determination processing related to the
embodiment of the invention.
Description of Embodiments
[0024]
Hereinbelow, an embodiment of a control device of
the air conditioning system, an air conditioning system,
and an anomaly determination method for an air
conditioning system related to the invention will be
described with reference to the drawings.
[0025]
Fig. 1 is a view illustrating a refrigerant system
of an air conditioning system 1 related to the present
embodiment. As illustrated in Fig. 1, the air
conditioning system 1 includes one outdoor unit B, and a
plurality of indoor units Al and A2 connected to the
outdoor unit B by a common refrigerant line 10. Although
a configuration in which two indoor units Al and A2 are
connected to one outdoor unit B is illustrated for
convenience in Fig. 1, the number of outdoor units B to be
installed and the number of indoor units Al and A2 to be
connected are not limited.
[0026]
The outdoor unit B includes, for example, a
compressor 11 that compresses and delivers a refrigerant,
a four-way valve 12 that switches a circulation direction
of a refrigerant, an outdoor heat exchanger 13 that
performs heat exchange between a refrigerant and ambient
air, an outdoor fan 15, an accumulator 16 that is provided
on a suction-side pipe of the compressor 11 from the
purpose of gas-liquid separation or the like of a
refrigerant, an outdoor-unit expansion valve 17 that is,
for example, an electronic expansion valve, and the like.
Additionally, the outdoor unit B is provided with various
sensors 20 (refer to Fig. 2), such as pressure sensors 21
(a high-pressure sensor 21 1 and a low-pressure sensor
21 2) that measure refrigerant pressures, an outdoor
temperature sensor 24 that measures refrigerant
temperature. In addition, the high-pressure sensor 21_1
measures the pressure of the refrigerant discharged from
the compressor 11, and the low-pressure sensor 21 2
measures the pressure of the refrigerant sent to the
compressor 11.
[0027]
The indoor units Al and A2 include an indoor heat
exchanger 31, an indoor fan 32, an indoor-unit expansion
valve 33, and the like, respectively. The two indoor
units Al and A2 are respectively connected to respective
refrigerant lines 10 that branch at a header 22 and a
distributor 23 within the outdoor unit B.
An indoor temperature sensor 35_1 measures the inlet
refrigerant temperature of the indoor heat exchanger 31,
an indoor temperature sensor 35 2 measures the
intermediate refrigerant temperature of the indoor heat
exchanger 31, and the indoor temperature sensor 35 3
measures the outlet refrigerant temperature of the indoor
heat exchanger 31.
[0028]
Fig. 2 is an electrical configuration diagram of the
air conditioning system 1 related to the present
embodiment. As illustrated in Fig. 2, the indoor units Al
and A2, the outdoor unit B, and a control device 3 are
connected together through a common bus 5, and are
configured to be capable of mutually transferring
information. In addition, the common bus 5 is an example
of a communication medium, and communication can be
wireless or wired.
The control device 3 is connected to a maintenance
inspection device 6 that performs maintenance inspection
through a communication medium 7, and is configured to be
capable of periodically transmitting operating data, or at
the time of occurrence of the anomaly, rapidly notifying
the maintenance inspection device of the effect.
[0029]
Here, in related-art air conditioning systems,
control devices are provided inside an indoor unit and an
outdoor unit, respectively. In contrast, in the present
embodiment, respective indoor-unit control parts 41_1 and
41_ 2 and an outdoor-unit control part 43 are provided
independently from the indoor units Al and A2 and the
outdoor unit B. Specifically, the indoor-unit control
part 41_ 1 that controls the indoor unit Al, the indoorunit
control part 41_2 that controls the indoor unit A2,
and the outdoor-unit control part 43 that controls the
outdoor unit B are mounted on the control device 3 serving
as a virtualized control part.
[0030]
That is, since the indoor-unit control parts 41 and
the outdoor-unit control part 43 are present independently
from the indoor units A and the outdoor unit B, the
configurations of the indoor units A and the outdoor unit
B are simplified. Moreover, for example, like
installation for only communication and actuator functions
of components, it is not necessary to load advanced
programs into the indoor units A and the outdoor unit B,
and replacement of the indoor units A and the outdoor unit
B can be easily performed. In addition, as long as the
indoor units Al and A2 or the outdoor unit B satisfies
specification, the indoor units A and the outdoor unit B
manufactured by a maker different from that of the control
device 3 may be adopted.
[0031]
That is, the indoor-unit control parts 41 1 and 41 2
and the outdoor-unit control part 43 are integrated in the
control device 3 having one kind of hardware, and
independent operations are made possible on the hardware
included in the control device 3. The control device 3
has a master control part 40 for making the indoor-unit
control parts 41_1 and 41_2 and the outdoor-unit control
part 43 virtually present within the control device.
[0032]
In the control device 3, the indoor-unit control
parts 41_ 1 and 41 _2 and the outdoor-unit control part 43
are configured to be capable of mutually transferring
information. Additionally, the indoor-unit control parts
41_ 1 and 41 _2 and the outdoor-unit control part 43 may
perform, for example, autonomous decentralized control for
making the individual control parts realize independent
autonomous decentralized controls while sharing
information. Here, the autonomous decentralized control
means that information is received from the sensors 20 and
other control parts (for example, the indoor-unit control
part 41 2 and the outdoor-unit control part 43 are
equivalent to the other control parts in the case of the
indoor-unit control part 41_1), and a predetermined
application gives control commands to the corresponding
indoor units Al and A2 or outdoor unit B (for example, the
indoor unit Al in the case of the indoor-unit control part
41 1) according to control rules with this information as
an input.
[0033]
In the indoor unit Al, indoor unit local controllers
52 that are respectively provided to correspond to various
machinery 51, such as the indoor fan 32 and the indoorunit
expansion valve 33 (refer to Fig. 1), are connected
to the common bus 5 through a gateway (communication
means) 53. In addition, although illustration is omitted,
the indoor unit A2 is also configured to be the same as
the indoor unit Al.
In the outdoor unit B, outdoor unit local
controllers 62 that are respectively provided to
correspond to various machinery 61, such as the compressor
11, the four-way valve 12, and an outdoor fan 13 (refer to
Fig. 1), are connected to the common bus 5 through a
gateway (communication means) 63.
[0034]
The gateways 53 and 63 are assemblies of functions
including, for example, a communication driver, an address
storage region, a machinery attribute storage region, a
configuration machinery information storage region, an OS,
and a communication framework.
The address storage region is a storage region for
storing addresses that are unique identification numbers
assigned in order to communicate with the control device 3
or the like.
Additionally, the machinery attribute storage region
is a storage region for storing its own attribute
information and attribute information about the machinery
51 and 61 to be held. For example, information, such as
information about whether there is an indoor unit or an
outdoor unit, capacity, installed sensors (for example, a
temperature sensor, a pressure sensor, and the like), and
information (for example, the number of fan taps, the full
pulse of valves, and) about the machinery, is stored.
[0035]
Moreover, the sensors 20 (for example, the pressure
sensors that measure the refrigerant pressures, the
temperature sensor that measures the refrigerant
temperature, and the like) provided in the indoor units Al
and A2 and the outdoor unit B are respectively connected
to the common bus 5 through an AD board 71. Here, in a
case where the measurement accuracy of the sensors 20 is
low, nodes having a correction function for correcting a
measurement value may be provided between the AD board 71
and the sensors 20. In this way, by giving the correction
function, it is possible to use sensors, which are
inexpensive and are not so high in measurement accuracy,
as the sensors 20.
[0036]
In such an air conditioning system 1, for example,
the indoor-unit control parts 41_1 and 41_2 of the control
device 3 acquire measurement data and control information
acquired from the sensors 20, the indoor unit local
controllers 52, and the outdoor unit local controllers 62
through the common bus 5, and executes a predetermined
indoor unit control program on the basis of the
measurement data, thereby outputting control commands to
the various machinery (for example, the indoor fan 32, the
indoor-unit expansion valve 33, and the like) provided the
indoor units Al and A2. The control commands are sent to
the indoor unit local controllers 52 through the common
bus 5 and the gateway 53. The indoor unit local
controllers 52 drive the corresponding pieces of machinery,
respectively, on the basis of the received control
commands. Accordingly, the control of the indoor units Al
and A2 based on the control commands is realized.
[0037]
Similarly, the outdoor-unit control part 43 of the
control device 3 acquires the measurement data and the
control information from the sensors 20, the indoor unit
local controllers 52, and the outdoor unit local
controllers 62 through the common bus 5, and executes a
predetermined outdoor unit control program on the basis of
these measurement data, thereby outputting control
commands to the various machinery (for example, the
compressor 11, the four-way valve 12, the outdoor heat
exchanger 13, the outdoor fan 15, the outdoor-unit
expansion valve 17, and the like) provided in the outdoor
unit B. The control commands are sent to the outdoor unit
local controllers 62 through the common bus 5 and the
gateway 63. The outdoor unit local controllers 62 drive
the corresponding pieces of machinery, respectively, on
the basis of the received control commands.
[0038]
The indoor units Al and A2 and the outdoor unit B
may be subjected to the autonomous decentralized control
by the indoor-unit control parts 41_1 and 41_2 and the
outdoor-unit control part 43, respectively. In this case,
the control rules are set between the indoor units Al and
A2 and the outdoor unit B, and the control parts perform
control, respectively, according to the control rules.
For example, if the refrigerant pressures are mentioned as
an example, in a case where the refrigerant pressures
acquired from sensors 20 is within a predetermined first
allowable fluctuation range, the indoor-unit control parts
41 1 and 41 2 determine control commands for making a user
or the like coincide actual temperatures and actual air
volumes with set temperatures and set air volumes, and
outputs the control commands to the indoor units Al and A2,
respectively, through the common bus 5. Here, the indoorunit
control parts 41_1 and 41_2 may cooperate to perform
mutual transfer of information, thereby determining the
respective control commands. Additionally, the outdoorunit
control part 43 determines output commands of the air
conditioning system 1 for maintaining the refrigerant
pressure at a predetermined second allowable fluctuation
range, for example, control commands regarding the
rotational speed of the compressor 11, the rotating speed
of the outdoor fan 15, and the like, and transmits the
control commands to the outdoor unit B through the common
bus 5.
For example, by setting the first allowable range to
be wider than the second allowable range, it is possible
for the outdoor-unit control part 43 to ascertain output
change information about the indoor units Al and A2 and
determine the behavior of the outdoor unit B.
[0039]
In addition, the control device 3, the indoor unit
local controllers 52, and the outdoor unit local
controllers 62 are constituted with, for example, a
central processing unit (CPU), a random access memory
(RAM), a read only memory (ROM), a computer-readable
storage medium, and the like. A series of processing for
realizing various functions are stored in the storage
medium or the like in the form of a program as an example,
and the various functions are realized when the CPU reads
this program to the RAM or the like to execute processing
of information and calculation processing. In addition, a
form in which this program is installed in advance in the
ROM or other storage media, a form in which this program
is provided after being stored in the computer-readable
storage medium, a form in which this program is
distributed through communication means in a wired or
wireless manner, or the like may be applied. The
computer-readable storage medium is a magnetic disk, a
magnetic-optical disk, a CD-ROM, a DVD-ROM, a
semiconductor memory, or the like.
[0040]
Here, in the related-art air conditioning systems
that control the outdoor unit and the indoor unit using
the different control devices, respectively, the outdoor
unit and the indoor unit are operated by different control
programs. Therefore, it is difficult to accurately
ascertain the operating state of the overall air
conditioning system. For this reason, in the related-art
air conditioning systems, it is necessary to collect and
manage data, such as the operating state and various state
quantities of the air conditioning system, using a server
or the like for remote monitoring.
Additionally, if the indoor units A and the outdoor
unit B manufactured by different makers are used for the
air conditioning system 1 related to the present
embodiment, it is necessary to determine whether or not
the machinery installed in these units is operating
correctly as the air conditioning system 1.
[0041]
Thus, the control device 3 of the air conditioning
system I related to the present embodiment includes an
anomaly determination control part 44.
In order to determine the operating state of the air
conditioning system 1, the anomaly determination control
part 44, compares a present operating state of the air
conditioning system 1 with a past operating state
associated with an equivalent load state, thereby executes
anomaly determination for determining the presence or
absence of an anomaly in the machinery. In addition, the
present operating state is, in other words, an operating
state under operation.
That is, the control device 3 performs passive
monitoring control for acquiring the operating state of
the air conditioning system 1 that varies according to
operated machinery. The operating state is a combination
of operating points of respective pieces of the machinery
installed in the indoor units A or the outdoor unit B, and
the state quantities of the air conditioning system 1.
The state quantities are, for example, the temperature of
the refrigerant, the pressure of the refrigerant, the flow
rate of the refrigerant, the degree of superheat, indoor
temperatures, current values of the compressor 11, and the
like that are measured by the sensors 20.
[0042]
Fig. 3 is a functional block diagram illustrating
the functions of the anomaly determination control part 44
in the control device 3 related to the present embodiment.
[0043]
The anomaly determination control part 44 includes a
state quantity acquisition unit 70, a storage unit 72, an
anomaly determination unit 74, and a refrigerant amount
calculation unit 76.
[0044]
The state quantity acquisition unit 70 acquires the
state quantities of the air conditioning system 1 from the
various sensors together with the operating points of the
respective pieces of machinery, as the operating state of
the air conditioning system 1.
[0045]
The storage unit 72 stores the operating state
acquired by the state quantity acquisition unit 70 in time
series and for each load state of the air conditioning
system 1.
[0046]
The anomaly determination unit 74 compares a present
operating state stored in the storage unit 72 with a past
operating state associated with an equivalent load state,
thereby determining the presence or absence of an anomaly
in the machinery.
[0047]
In addition, the equivalent load state means that
outdoor air temperature, the number of operating indoor
units A, or the like is the same or within an allowable
error range even if the number of operating indoor units A
is different.
Additionally, the past operating state may be an own
past operating state, for example, may be a past operating
state of another air conditioning system 1 with the same
configuration of the machinery within the same property
and the same area. In the case of a form in which
comparison with the past operating state of the other air
conditioning system 1 is performed, for example, the past
operating state of the other air conditioning system 1 is
stored in the storage unit 72 through a communication
network.
[0048]
The refrigerant amount calculation unit 76 executes
refrigerant amount calculation processing for calculating
the amount of the refrigerant within the air conditioning
system 1 on the basis of the acquired state quantities.
[0049]
In this way, in the anomaly determination related to
the present embodiment, a change in the operating state in
a case where an anomaly has occurred in the machinery
becomes clear by comparing the present and past operating
states of the air conditioning system 1 in the equivalent
load state. Therefore, in the anomaly determination
related to the present embodiment, it is possible to more
simply and accurately ascertain the operating state of the
air conditioning system 1.
[0050]
Additionally, in the air conditioning system 1
related to the present embodiment, one control device 3
controls the indoor units A and the outdoor unit B. Thus,
the control states of the respective pieces of machinery,
the various state quantities in the air conditioning
system 1, and the like can be managed by the control
device 3. That is, in the air conditioning system 1
related to the present embodiment, the operating state of
the air conditioning system 1 can be ascertained simply
and accurately without using the server for remote
monitoring like the related-art air conditioning systems.
Additionally, in the air conditioning system 1
related to the present embodiment, even if the indoor
units A and the outdoor unit B manufactured by different
makers are used, the presence or absence of an anomaly is
determined by associating the operating points and by
comparing the state quantities of these pieces of
machinery with each other and the present and past
operating states with each other. Thus, it is possible to
accurately ascertain the influence that the operation of
the machinery has on the air conditioning system 1.
[0051]
Additionally, in the related-art air conditioning
systems in which the presence or absence of an anomaly, or
the like is monitored remotely, a number of pieces of
machinery are installed. Thus, the amount of operating
data to be transmitted to the server or the like for
remote monitoring is huge, and it is difficult to
accurately and rapidly ascertain the state of the air
conditioning system and to determine the presence or
absence of an anomaly.
Thus, the above-described state quantity acquisition
unit 70 acquires a predetermined state quantity that
fluctuates more easily according to the operation of the
machinery. That is, sensors 20 that acquire state
quantities according to machinery of which anomalies are
determined are determined in advance.
In this way, in the air conditioning system 1
related to this configuration, the presence or absence of
an anomaly in the machinery is determined only on the
basis of the predetermined state quantities that fluctuate
more easily according to the operation of the machinery.
Thus, the operating state of the air conditioning system 1
can be determined earlier.
[0052]
The following Table 1 is a table showing an example
of the combination between machinery of which anomalies
are determined and operating states to be compared
therewith, in the anomaly determination.
[0053]
[Table 1]
Machinery Operating State Method for Determining Anomaly
Indoor-Unit
Expansion Valve
Opening degree
and superheat
degree of
.
indoor-unit
expansion valve
- During cooling
Sticking (step-out or the like)
Opening degree of indoor-unit expansion
valve is minimum opening degree, and superheat
degree is predetermined temperature or lower
Biting of foreign matter
Present superheat degree is high
compared to past superheat degree
- During heating
Sticking (step-out or the like)
Opening degree of indoor-unit expansion
valve is maximum opening degree, and
supercooling or high pressure is predetermined
value or higher
Biting of foreign matter
Present supercooling degree (high
pressure) is high compared to past supercooling
degree (high pressure)
Compressor
Rotational
speed and
current value
of compressor
Present current value is different from past
current value by predetermined value or higher
Four-Way Valve
Flow direction
of refrigerant
- During cooling
Value of outdoor temperature sensor 24 > value
of indoor temperature sensor 35_3
- During heating
Value of outdoor temperature sensor 24 < value
of indoor temperature sensor 35 3
Indoor-Unit
Expansion Valve
Opening degree
and superheat
degree of
outdoor-unit
expansion valve
- During cooling
Sticking (step-out or the like)
Biting of foreign matter
Present high pressure is high compared
to high pressure in past equivalent operation
- During heating
Sticking (step-out or the like)
Opening degree of outdoor-unit expansion
valve is minimum opening degree, and superheat
degree is predetermined temperature or lower
Biting of foreign matter
Present superheat degree is high
compared to past superheat degree
[0054]
In a case where machinery of which an anomaly is
determined is the indoor-unit expansion valve 33, a
present opening degree and a present superheat degree and
a past opening degree and a past superheat degree of the
indoor-unit expansion valve 33 in an equivalent load state
are compared to each other as comparison between the
operating states, for example, in the case of a cooling
operation. That is, the opening degree of the indoor-unit
expansion valve 33 is an operating point of the machinery
and the superheat degree is a state quantity. Since it is
verified in advance that the indoor-unit expansion valve
33 is operating in a predetermined control area, the
anomaly determination for the indoor-unit expansion valve
33 is performed on the basis of the magnitude of the
opening degree and its accompanying superheat degree of
the indoor-unit expansion valve 33.
[0055]
In a case where the present opening degree of the
indoor-unit expansion valve 33 is different from the past
opening degree by a predetermined value or more, it is
determined that an anomaly occurs.
Also, in a case where the present opening degree of
the indoor-unit expansion valve 33 is a minimum opening
degree and the present superheat degree thereof is a
predetermined temperature or lower, it is determined that
an anomaly (step-out or the like) in which the indoor-unit
expansion valve 33 sticks occurs.
Additionally, in a case where the present superheat
degree is a predetermined value (for example, 10°C) or
high compared to the past superheat degree, it is
determined that an anomaly in which the indoor-unit
expansion valve 33 is not closed occurs. It is considered
that the cause of the anomaly in which the indoor-unit
expansion valve 33 is not closed is biting or the like of
foreign matter.
[0056]
On the other hand, in the case of a heating
operation, in a case where the opening degree of the
indoor-unit expansion valve 33 is a maximum opening degree
and supercooling or high pressure is a predetermined value
or higher, it is determined that an anomaly (step-out or
the like) in which the indoor-unit expansion valve 33
sticks occurs. Additionally, in a case where a present
supercooling degree (high pressure) is high compared to
the past supercooling degree (high pressure), it
determined that an anomaly in which the indoor-unit
expansion valve 33 is not closed due to biting or the like
of foreign matter occurs.
[0057]
In a case where machinery of which an anomaly is
determined is the compressor 11, a present current value
and a past current value with respect to the rotational
speed of the compressor 11 in an equivalent load state are
compared to each other as the comparison between operating
states. That is, the rotational speed of the compressor
11 is an operating point of the machinery, and the current
value of the compressor 11 is a state quantity. In this
way, the presence or absence of an anomaly of the
compressor 11 is directly determined using a current value
during the operation of the compressor 11.
Also, in a case where the present current values is
different from the past current value by a predetermined
value (for example, 2A) or higher, it is determined that
an anomaly occurs.
[0058]
In a case where machinery of which an anomaly is
determined is the four-way valve 12, whether or not the
four-way valve 12 is functioning normally is determined on
the basis of a flow direction of the refrigerant during
the cooling operation or the heating operation. That is,
the valve position of the four-way valve 12 is an
operating point of the machinery.
State quantities acquired in this case are values of
any of the indoor temperature sensors 35_1, 35_2, and 35_3
and the outdoor temperature sensor 24. This is because
the flow direction during the cooling operation and the
flow direction during the heating operation are determined
uniquely; therefore determination on whether or not the
four-way valve 12 is functioning normally is possible if
the temperatures of the indoor units A and the outdoor
unit B are acquired. Specifically, if the four-way valve
12 is functioning normally during the cooling operation,
the value of the outdoor temperature sensor 24 becomes
higher than the value of indoor temperature sensor 35_3 or
the like. On the other hand, if the four-way valve 12 is
functioning normally during the heating operation, the
value of the outdoor temperature sensor 24 becomes lower
than the value of indoor temperature sensor 35_3 or the
like.
[0059]
In a case where machinery of which an anomaly is
determined is the outdoor-unit expansion valve 17, similar
to the indoor-unit expansion valve 33, a present opening
degree and a present superheat degree and a past opening
degree and a past superheat degree of the outdoor-unit
expansion valve 17 in an equivalent load state are
compared to each other as the comparison between the
operating states, for example, in the case of the heating
operation. On the other hand, in the case of cooling
operation, the presence or absence of an anomaly, such as
sticking (step-out or the like) of the outdoor-unit
expansion valve 17 and biting of foreign matter, is
determined depending on whether or not a present high
pressure is high compared to a past high pressure during
an equivalent operation.
[0060]
In a case where it is determined that an anomaly
occurs in the machinery, it is preferable that reduction
determination of the amount of the refrigerant is
performed by the control device 3.
As the reduction determination of the amount of the
refrigerant, during the cooling operation, reduction of
the amount of the refrigerant is determined on the basis
of the opening degree of the indoor-unit expansion valve
33 and the superheat degree of an evaporator outlet.
Specifically, irrespective of an actual superheat degree
does not reach a set target superheat degree, it is
determined that the amount of the refrigerant is reduced
in a case where the indoor-unit expansion valve 33 is
fully open. That is, the reason why the indoor-unit
expansion valve 33 is fully open is not based on an
anomaly of the indoor-unit expansion valve 33, and
reduction of the amount of the refrigerant becomes a cause.
Additionally, during the heating operation,
reduction of the amount of the refrigerant is determined
similar to during the cooling on the basis of the opening
degree of the outdoor-unit expansion valve 17 and the
superheat degree of the evaporator outlet.
[0061]
In addition, since gas refrigerant is also reduced
if the amount of the refrigerant is reduced, compared to a
case where the amount of the refrigerant is not reduced, a
drop in the high or low pressure and a drop in the
discharge temperature of the compressor 11 occur.
Accordingly, although the control device 3 may determine
that the amount of the refrigerant is being reduced, the
same phenomenon occurs even due to an anomaly of the
compressor 11. Therefore, it is more preferable to
determine the reduction of the amount of the refrigerant
on the basis of the opening degree of the above-described
indoor-unit expansion valve 33 and the superheat degree of
the evaporator outlet.
[0062]
Fig. 4 is a flowchart illustrating a flow of anomaly
determination processing (anomaly determination program)
related to the present embodiment. The anomaly
determination processing is executed by the control device
3.
[0063]
First, in Step 100, it is determined whether or not
a predetermined cumulative operation time (for example, 50
hours) has passed from the end of the anomaly
determination processing executed previously. In a case
where the determination is positive, the processing
proceeds to Step 102.
[0064]
The anomaly determination is performed in Step 102.
[0065]
In the next Step 104, it is determined whether or
not there is any machinery showing an anomaly depending on
the anomaly determination. In a case where the
determination is positive, the processing proceeds to Step
106, and in a case where the determination is negative,
the processing returns to Step 100.
[0066]
In Step 106, in order to solve the anomaly, the
operation of the air conditioning system 1 is stopped and
the anomaly determination processing is ended.
[0067]
Fig. 5 is a flowchart illustrating an example of the
anomaly determination executed in Step 102. In Fig. 5,
the presence or absence of an anomaly of the indoor-unit
expansion valve 33 is determined as an example.
[0068]
First, in Step 200, the operating state of the air
conditioning system 1 is acquired, and is stored in the
storage unit 72 for each load state.
[0069]
In the next Step 202, it is determined whether or
not there is any difference of a predetermined value
higher between the present opening degree and the past
opening degree of the indoor-unit expansion valve 33 in
the equivalent load state. In a case where the
determination is positive, the processing proceeds to Step
204, and in a case where the determination is negative,
the processing returns to Step 210.
[0070]
In the next Step 204, is determined whether or
not the present superheat degree is a predetermined value
(for example, 10°C) higher than the past superheat degree
in the equivalent load state. In a case where the
determination is positive, the processing proceeds to Step
206, and in a case where the determination is negative,
the processing returns to Step 208.
[0071]
In Step 206, an anomaly occurrence flag showing that
an anomaly occurs in the indoor-unit expansion valve 33 is
set.
[0072]
In Step 208, it is determined whether or not the
present opening degree of the indoor-unit expansion valve
33 is a minimum opening degree and the superheat degree is
a predetermined temperature (for example, 2°C) or lower
that is regarded as being substantially zero. In a case
where the determination is positive, the processing
proceeds to Step 206, and in a case where the
determination is negative, the processing returns to Step
210.
[0073]
In Step 210, an anomaly non-occurrence flag showing
that no anomaly occurs in the indoor-unit expansion valve
33 is set.
[0074]
Accordingly, in the above-described Step 104, in a
case where the anomaly occurrence flag is set, it is
determined that there is any machinery showing an anomaly.
[0075]
By virtue of the anomaly determination described
above, an anomaly in the machinery can be detected before
a malfunction of the air conditioning system 1, and the
anomaly determination at a constant level using data is
made possible, not based on determination resulting from a
human being's thought.
Additionally, by collecting only the results
originating from a malfunction prediction operation and
aggregating the verification results of the machinery and
data of incompatible sites, statistical data of machinery
in which a problem occurs in quality, such as which kind
of problem occurs in a combination of any machinery of any
maker and any indoor unit of any maker, is obtained. It
is also possible to reflect this result on an immediate
response to an anomaly or design change.
Additionally, it is possible to classify, for
example, the capacity of the indoor units A being
insufficient (a selection mistake, performance
degradation) with respect to a load generated in an indoor
chamber, and the like depending on the operating state.
As a result, the range of compensation for incompatibility
can be limited.
[0076]
Next, the refrigerant amount calculation processing
executed in the refrigerant amount calculation unit 76 of
the control device 3 will be described.
As described above, since the control device 3
controls the indoor units A and the outdoor unit B, the
various state quantities and the like in the air
conditioning system I can be managed.
Thus, in the refrigerant amount calculation
processing, the amount of the refrigerant within the air
conditioning system 1 is calculated using the state
quantities of the refrigerant under the operation of the
air conditioning system 1. Accordingly, the state of an
increase and a decrease in the amount of the refrigerant
can be managed in time series, and the presence or absence
of leakage of the refrigerant can be determined.
[0077]
The refrigerant amount calculation processing
related to the present embodiment divides the air
conditioning system 1 into a plurality of regions
(hereinafter a "divided regions") virtually.
An example of the division are 1. Outdoor heat
exchanger 13, 2. Indoor heat exchanger 31, 3. Gas pipe, 4.
Liquid pipe, 5. Pressure vessel, and 6. In-machinery line.
The gas pipe is a pipe through which a gas
refrigerant that faces from the indoor units A to the
outdoor unit B flows, in the refrigerant line 10. The
liquid pipe is a line through which a liquid refrigerant
that faces from the outdoor unit B to the indoor units A
flows, in the refrigerant line 10.
The pressure vessel is the compressor 11 and the
accumulator 16.
The in-machinery line is a line that connects the
respective pieces of machinery within the indoor units A,
and a line that connects the respective pieces of
machinery within the outdoor unit B.
[0078]
The amount of the refrigerant can be calculated, for
example, by multiplying the density (kg/m3 ) of the
refrigerant by the internal volume (m 3 ) of the lines.
The refrigerant density is calculated on the basis
of the state quantities measured by the pressure sensors
and the temperature sensor included in the air
conditioning system 1. Additionally, the lengths,
internal diameters, and the like of respective lines
through that a refrigerant flows are obtained in advance
as design values, and the internal volumes of the lines,
are calculated from the design values. Also, the amount
of the refrigerant is calculated for each divided region,
and the total of these amounts is estimated as the amount
of the refrigerant circulating through the air
conditioning system 1.
[0079]
Next, a method for calculating the amount of the
refrigerant will be described for each divided region
taking the case of the cooling operation as an example.
[0080]
1. Outdoor Heat Exchanger 13 (Condenser)
In the outdoor heat exchanger 13, a liquid phase and
a gas phase are present in a mixed manner, and the amount
of the refrigerant required in the operating state varies
greatly depending on a liquid phase region generated
inside the outdoor heat exchanger. Thus, the control
device 3 stores a map, in which the amount of the
refrigerant within the outdoor heat exchanger 13 in the
operating state of the air conditioning system 1 is
predicted, in advance. In this map, for example, a
horizontal axis is high pressure and a vertical axis is
the amount of the refrigerant, and a relationship between
the high pressure and the amount of the refrigerant
according to different supercooling degrees is shown.
That is, in the refrigerant amount calculation
processing, the amount of the refrigerant is calculated by
reading the amount of the refrigerant according to a
measurement value of the high-pressure sensor 21_1 and a
supercooling degree from the map.
In addition, the invention is not limited, and the
amount of the refrigerant within the outdoor heat
exchanger 13 may be calculated by calculating the mean
density of the refrigerant within the outdoor heat
exchanger 13 on the basis of the pressure and temperature
in the outdoor heat exchanger 13, and multiplying the
density by a volume within the outdoor heat exchanger 13.
[0081]
2. Indoor Heat Exchanger 31 (Evaporator)
In the indoor heat exchanger 31, the liquid phase
and the gas phase are also present in a mixed manner.
Thus, similar to the outdoor heat exchanger 13, the
control device 3 stores a map, in which the amount of the
refrigerant within the indoor heat exchanger 31 in the
operating state of the air conditioning system 1 is
predicted, in advance. In this map, for example, a
horizontal axis is low pressure and a vertical axis is the
amount of the refrigerant, and a relationship between the
low pressure and the amount of the refrigerant according
to superheat degrees is shown.
That is, in the refrigerant amount calculation
processing, the amount of the refrigerant is calculated by
reading the amount of the refrigerant according to the
measurement value of the low-pressure sensor 21_2 and a
superheat degree from the map.
In addition, the invention is not limited, and the
amount of the refrigerant within the indoor heat exchanger
31 may be calculated by calculating the mean density of
the refrigerant within the indoor heat exchanger 31 on the
basis of the pressure and temperature in the indoor heat
exchanger 31, and multiplying the density by a volume
within the indoor heat exchanger 31.
[0082]
3. Gas Pipe
In the refrigerant amount calculation processing,
the amount of the refrigerant is calculated by calculating
a gas density from the measurement value of the lowpressure
sensor 21_2, and the measurement value of the
temperature sensor in the gas pipe, and multiplying this
gas density by the internal volume of the gas pipe.
[0083]
4. Liquid Pipe
In the refrigerant amount calculation processing,
the amount of the refrigerant is calculated by calculating
a liquid density from the measurement value of the lowpressure
sensor 21_ 2, and the measurement value of the
temperature sensor in the liquid pipe, and multiplying
this liquid density by the internal volume of the liquid
pipe.
[0084]
5. Pressure Vessel
In the refrigerant amount calculation processing,
the amount of the refrigerant is calculated by calculating
a gas density from the measurement value of the lowpressure
sensor 21_ 2, and the measurement value of the
temperature sensor in the pressure vessel, and multiplying
this gas density by the internal volume of the pressure
vessel.
In addition, since there is no liquid into the
accumulator 16 during the operation of the air
conditioning system 1, it can be assumed that a
substantially single-phase superheated gas present inside
the pressure vessel.
[0085]
6. In-machinery Line
As the in-machinery line, there is a line a pipe
(hereinafter referred to as a "liquid line") through which
a liquid phase flows, and a line (hereinafter referred to
a "gas line") through which a gas phase flows. Thus, in
the refrigerant amount calculation processing, the liquid
line and the gas line are virtually divided according to
the operating state of the air conditioning system 1. In
the refrigerant amount calculation processing, the amount
of the refrigerant within the liquid line is obtained by
multiplying the liquid density calculated from the
pressure and temperature in the liquid line by the
internal volume of the liquid line, and the amount of the
refrigerant within the gas line is obtained by multiplying
the gas density calculated from the pressure and
temperature in the gas line by the internal volume of the
gas line. The sum of the amount of the refrigerant within
the liquid line and the amount of the refrigerant within
the gas line becomes the amount of the refrigerant in the
in-machinery line.
[0086]
In addition, the amount of the refrigerant is not
limited to storing a correlation equation using the
control device 3 and being calculated on the basis of this
correlation equation, as described above. The control
device 3 may be connected to an external server, and the
amount of the refrigerant may be calculated in this server.
[0087]
Fig. 6 is a flowchart illustrating a flow of
refrigerant amount determination processing related to the
present embodiment. The refrigerant amount determination
processing is executed by the control device 3.
[0088]
First, in Step 300, it is determined whether or not
a predetermined cumulative operation time (for example, 50
hours) has passed from the end of the refrigerant amount
determination processing executed previously. In a case
where the determination is positive, the processing
proceeds to Step 302.
[0089]
In Step 302, the above-described refrigerant amount
calculation processing is performed, and the calculated
amount of the refrigerant is stored.
[0090]
In the next Step 304, it is determined whether or
not the amount of the refrigerant calculated this time is
reduced by a predetermined amount or more, compared to the
amount of the refrigerant calculated previously. This
predetermined amount may be the ratio of the amount of the
refrigerant calculated previously to the amount of the
refrigerant calculated this time, or may be a difference
(absolute value) between the amount of the refrigerant
calculated previously and the amount of the refrigerant
calculated this time. For example, in a case where the
predetermined amount is calculated depending on the ratio
and in a case where the amount of the refrigerant
previously calculated is reduced by 10% or more compared
to the amount of the refrigerant calculated this time, the
answer is set to be positive in Step 304 and the
processing proceeds to Step 306. On the other hand, in a
case where the amount of the reduction is less than 10%,
it is determined that the answer is negative, and the
processing returns to Step 300.
That is, in a case where the reduction of the amount
of the refrigerant is a predetermined amount or more, an
anomaly in which the refrigerant leaks out from the air
conditioning system 1 occurs.
[0091]
In Step 306, an alarm showing that the anomaly
occurs is activated, for example, through the maintenance
inspection device 6, and the refrigerant amount
determination processing is ended.
[0092]
As described above, the control device 3 for the air
conditioning system 1 related to the present embodiment
includes the outdoor-unit control part 43 capable of
communication with the outdoor unit B through the
communication medium, the outdoor-unit control part 43
acquiring, through the communication medium, the
information about the machinery installed in the outdoor
unit B and outputting control commands to the machinery
installed in the outdoor unit B; and an indoor-unit
control part 41 capable of communication with the indoor
units A through the communication medium, the indoor-unit
control part 41 acquiring, through the communication
medium, the information about the machinery installed in
the indoor units A and outputting the control commands to
the machinery installed in the indoor units A. The
control device 3 stores the operating state of the air
conditioning system 1 for each load state of the air
conditioning system 1 and determines the presence or
absence of an anomaly in the machinery by comparing the
present operating state and the past operating state
associated with the equivalent load state.
[0093]
In this way, since, the control device 3 compares
the during-operation and past operating states of the air
conditioning system 1 in the equivalent load state, a
change in the operating state in a case where an anomaly
has occurred in the machinery becomes clear, and the
operating state of the air conditioning system 1 can be
ascertained more simply and accurately.
[0094]
Although the invention has been described above
using the above embodiment, the technical scope of the
invention is not limited to the scope described in the
above embodiment. Various changes or improvements can be
added to the above embodiment without departing from the
concept of the invention, and forms to which these changes
or improvements are added are also included in the
technical scope of the invention. Additionally, the above
embodiment may be appropriately combined.
[0095]
For example, a form in which the anomaly
determination processing and the refrigerant amount
determination processing are executed after the passage of
the predetermined cumulative operation time from the end
of each processing executed previously has been described
in the above embodiment. However, the invention is not
limited to this, and may have a form in which each
processing is executed at predetermined time intervals,
such as once a week.
[0096]
Additionally, the flow of the anomaly determination
processing or the refrigerant amount determination
processing described in the above embodiment is also an
example, unnecessary steps may be eliminated, new steps
may be added, or processing order may be changed, without
departing from the main point of the invention.
Reference Signs List
[0097]
1: AIR CONDITIONING SYSTEM
3: CONTROL DEVICE
41: INDOOR-UNIT CONTROL PART
43: OUTDOOR-UNIT CONTROL PART
72: STORAGE UNIT
74: ANOMALY DETERMINATION UNIT
A: INDOOR UNIT
B: OUTDOOR UNIT
4)9_ diaJam,
Claims
[Claim 1]
A control device for an air conditioning system
including one or a plurality of outdoor units and one or a
plurality of indoor units, the control device comprising:
an outdoor-unit control part capable of
communication with the outdoor unit through a
communication medium, the outdoor-unit control part
acquiring, through the communication medium, information
about machinery installed in the outdoor unit and
outputting a control command to the machinery installed in
the outdoor unit;
an indoor-unit control part capable of communication
with the indoor unit through the communication medium, the
indoor-unit control part acquiring, through the
communication medium, information about machinery
installed in the indoor unit and outputting a control
command to the machinery installed in the indoor unit;
storage means for storing an operating state of the
air conditioning system for each load state of the air
conditioning system; and
anomaly determination means for determining the
presence or absence of an anomaly in the machinery by
comparing a present operating state and a past operating
state associated with an equivalent load state.
[Claim 2]
The control device for an air conditioning system
according to Claim 1,
wherein the anomaly determination means determines
the presence or absence of an anomaly in the machinery on
the basis of a predetermined state quantity of the air
conditioning system that fluctuates more easily according
to the operation of the machinery.
[Claim 3]
The control device for an air conditioning system
according to Claim 1 or 2,
wherein the amount of a refrigerant within the air
conditioning system is calculated on the basis of a state
quantity of the air conditioning system.
[Claim 4]
An air conditioning system comprising:
one or a plurality of outdoor units;
one or a plurality of indoor units; and
the control device according to any one of Claims 1
to 3.
[Claim 5]
A method for determining an anomaly of an air
conditioning system including one or a plurality of
outdoor units and one or a plurality of indoor units, an
outdoor-unit control part capable of communication with
- ,yr - ,s73
the outdoor unit through a communication medium, the
outdoor-unit control part acquiring, through the
communication medium, information about machinery
installed in the outdoor unit and outputting a control
command to the machinery installed in the outdoor unit,
and an indoor-unit control part capable of communication
with the indoor unit through the communication medium, the
indoor-unit control part acquiring, through the
communication medium, information about machinery
installed in the indoor unit and outputting a control
command to the machinery installed in the indoor unit, the
method comprising:
storing an operating state of the air conditioning
system for each load state of the air conditioning system;
and
determining the presence or absence of an anomaly in
the machinery by comparing a present operating state and a
past operating state associated with an equivalent load
state.