US20020162342A1

US20020162342A1 - Method for controlling air conditioner/heater by thermal storage

Info

Publication number: US20020162342A1
Application number: US09/845,169
Authority: US
Inventors: Kuo-Liang Weng; Ming-Tsun Ke; Jing-Wen Weng
Original assignee: Individual
Current assignee: Cohand Technology Co Ltd
Priority date: 2001-05-01
Filing date: 2001-05-01
Publication date: 2002-11-07

Abstract

A process for controlling an air conditioner/heater by thermal storage comprises the steps of sending ambient temperature of at least one enclosed space sensed by a plurality of sensors to CPU for comparison with a predetermined value; switching to operate in one of air conditioning, heating, and hot water supplying modes; and if switching to the air conditioning mode and the temperature of thermal storage is less than or equal to the predetermined value, a compressor is turned off, an outdoor fan motor is turned off, and a solenoid-controlled valve is turned on to cause the process to enter into a melting cycle. With this automatic switching, the operation is maintained at an optimum, resulting in an increase of thermal efficiency.

Description

FIELD OF THE INVENTION

The present invention relates to air conditioner/heater and more particularly to a method for controlling the operation of air conditioner/heater by thermal storage.

BACKGROUND OF THE INVENTION

A

conventional air conditioner

1 is shown in FIG. 1. The air conditioner 1 comprises a compressor 11, a heat exchanger (e.g., condenser) 12, a fan motor 13, a filter 14, and a coolant flow controller 15 (all above components are installed in outdoor). The air conditioner 1 further comprises a heat exchanger (e.g., evaporator) 16 and a fan motor 17 (both are installed in indoor). With this configuration, it is possible to air condition an enclosed space (AO). However, the previous design suffered from several disadvantages. For example, the rotating speed of each fan motor is fixed, i.e., it is not adapted to ambient temperature (or coil temperature). As understood that, heat exchange capability of air conditioner is proportional to wind speed which in turn is proportional to motor speed. Thus, heat exchange capability is proportional to motor speed. Hence, the heat exchange capability of the air conditioner is low inherently due to such fixed rotating speed of fan motor, resulting in a waste of energy. Further, the capability of heat dissipation of condenser is always larger than the capability of heat absorption of evaporator. Hence, it is difficult for such conventional air conditioner to operate as heater when desired. Furthermore, the thermal efficiency is unacceptable low even when the air conditioner operates as heater. Thus, improvement exists.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a process for controlling an air conditioner/heater by the thermal storage comprising the steps of: sending ambient temperature of at least one enclosed space sensed by a plurality of sensors to a central processing unit (CPU) for comparison with a predetermined value; switching to operate in one of air conditioning, heating, and hot water supplying modes; and if switching to the air conditioning mode and the temperature of thermal storage is less than or equal to the predetermined value, a compressor is turned off, an outdoor fan motor is turned off, and a solenoid-controlled valve is turned on to cause the process to enter into a melting cycle. With this automatic switching, the operation is maintained at an optimum, resulting in an increase of thermal efficiency.

The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing of a conventional air conditioner; [0005]
FIG. 2 is a schematic drawing of a first preferred embodiment of air conditioner/heater according to the invention; [0006]
FIG. 3 is another schematic drawing of the first preferred embodiment shown in FIG. 2; [0007]
FIG. 4 is a schematic drawing of a second preferred embodiment of air conditioner/heater according to the invention; [0008]
FIG. 5 is another schematic drawing of the second preferred embodiment shown in FIG. 4; [0009]
FIG. 6 is a schematic drawing of a third preferred embodiment of air conditioner/heater according to the invention; [0010]
FIG. 7 is another schematic drawing of the third preferred embodiment shown in FIG. 6; [0011]
FIG. 8 is a schematic drawing of a fourth preferred embodiment of air conditioner/heater according to the invention; [0012]
FIG. 9 is another schematic drawing of the fourth preferred embodiment shown in FIG. 8; [0013]
FIG. 10 is a first flow chart of the control process of the invention; [0014]
FIG. 11 is a second flow chart of the control process of the invention; [0015]
FIG. 12 is a third flow chart of the control process of the invention; [0016]
FIG. 13 is a fourth flow chart of the control process of the invention; [0017]
FIG. 14 is a fifth flow chart of the control process of the invention; [0018]
FIG. 15 is a sixth flow chart of the control process of the invention; [0019]
FIG. 16 is a graph illustrating the rotating speed of indoor fan motor versus temperature in air conditioning mode; [0020]
FIG. 17 is a graph illustrating the rotating speed of outdoor fan motor versus temperature in air conditioning mode; [0021]
FIG. 18 is a graph illustrating the rotating speed of indoor fan motor versus temperature in heating mode; [0022]
FIG. 19 is a graph illustrating the rotating speed of outdoor fan motor versus temperature in heating mode; [0023]
FIG. 20 is a first graph illustrating the operation of compressor; [0024]
FIG. 21 is a second graph illustrating the operation of compressor; [0025]
FIG. 22 is a third graph illustrating the operation of compressor; [0026]
FIG. 23 is a fourth graph illustrating the operation of compressor; [0027]
FIG. 24 is a fifth graph illustrating the operation of compressor; and [0028]
FIG. 25 is a sixth graph illustrating the operation of compressor.[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 2 and 3, there is shown a first preferred embodiment of air conditioner/[0030] heater 2 constructed in accordance with the invention. The air conditioner/heater 2 is activated to air condition/heat a single room (i.e., enclosed space) A1. That is, this is a one-to-one mode. Air conditioner/heater 2 comprises a compressor 21, a heat exchanger 23, a fan motor 24, a filter 25, and a coolant flow controller 26 (all above components are installed outside the enclosed space A1). Air conditioner/heater 2 further comprises a heat exchanger 27, a fan motor 28, a thermal storage 29, a throttle valve K1, and a solenoid-controlled valve SV1 (all are installed indoors). The air conditioner/heater 2 is controlled by a central processing unit (CPU) 20 through associated components such as a directional-control valve 22, a defrost bypass valve SV-a, a plurality of sensors B1, C1, D1, and E1, and a control panel F1. With this system, it is possible to air condition, heat, or supply hot water to an enclosed space A1 (FIG. 2). CPU 20 may compare sensed values Tie, Tic, Toe, Toc, Ta, Tei, and Teh obtained from sensors B1, C1, D1 and E1 with default values Ties, Tics, Toes, Tocs, Tas, Teis, and Tehs. Accordingly, CPU 20 may control the on-off of compressor 21, the switch of directional-control valve 22 (i.e., switch between air conditioning and heating modes), the speed selections of fan motors 24 and 28, and the on-off of defrost bypass valve SV-a. Directional-control valve 22 may be switched to permit a specific coolant to flow through by the selection of air conditioning/heating mode (i.e., either in the case shown in FIG. 2 or FIG. 3). Sensors B1, C1, D1, and E1 are located on outdoor heat exchanger 23, indoor heat exchanger 27, enclosed space A1, and thermal storage 29 respectively for sensing temperatures in order to obtain sensed values Tie, Tic, Toe, Toc, Ta, Tei, and Teh which are further sent to CPU 20. Control panel F1 is operable to set indoor temperature Tas and other functionalities. Defrost bypass valve SV-a is controlled by CPU 20 in the defrost cycle. Throttle valve K1 is mounted on the line between thermal storage 29 and solenoid-controlled valve SV1. Throttle valve K1 is operable to regulate coolant flow into thermal storage 29 and indoor heat exchanger 28 in the air conditioning cycle. Sensor B1 can sense the coil temperature of outdoor heat exchanger 23 (i.e., sensed values Toe (evaporation temperature of heating cycle) and Toc (condensation temperature of air conditioning cycle)). Sensor C1 can sense the coil temperature of indoor heat exchanger 27 (i.e., sensed values Tie (evaporation temperature of air conditioning cycle) and Tic (condensation temperature of heating cycle)). Sensor D1 can sense the ambient temperature of enclosed space A1 (i.e., sensed value Ta). Sensor E1 can sense the temperature of thermal storage 29 (i.e., sensed values Tei (temperature of ice forming in air conditioning cycle) and Teh (temperature of thermal storage in heating cycle)). The corresponding relationship between sensed values Tie, Tic, Toe, Toc, Ta, Tei, and Teh and default values Ties, Tics, Toes, Tocs, Tas, Teis, and Tehs is as follows: (1) In air conditioning cycle: Ta is corresponding to Tas, Tie is corresponding to Ties, Toc is corresponding to Tocs, and Tei is corresponding to Teis. (2) In heating cycle: Ta is corresponding to Tas, Tic is corresponding to Tics, Toc is corresponding to Tocs, and Teh is corresponding to Tehs. A heat exchange pipe (not shown) containing a suitable amount of thermal storage medium is provided in thermal storage 29 and is in fluid communication with indoor heat exchanger 27 through a line. Thermal storage 29 is capable of storing ice in air conditioning cycle and accumulating heat in heating cycle respectively.
Referring to FIGS. 4 and 5, there is shown a second preferred embodiment of air conditioner/[0031] heater 3 constructed in accordance with the invention. The air conditioner/heater 3 is activated to air condition/heat a plurality of rooms. That is, this is a one-to-many mode. Air conditioner/heater 3 comprises a compressor 31, a heat exchanger 33, a fan motor 34, a filter 35, and a plurality of coolant flow controllers 362 and 363 (all above components are installed outside enclosed spaces A2 and A3). Air conditioner/heater 3 further comprises a plurality of heat exchangers 372 and 373, a plurality of thermal storages 392 and 393, a plurality of fan motors 382 and 383, a plurality of throttle valves K2 and K3, a plurality of solenoid-controlled valves SV2 and SV3, and a plurality of defrost bypass valves SV-b and SV-C (all are installed in the enclosed spaces A2 and A3 respectively). Similar to the first embodiment, the air conditioner/heater 3 is controlled by a CPU 30 through associated components such as a directional-control valve 32, a plurality of sensors B2, C2, C3, D2, and D3, and a plurality of control panels F2 and F3. The differences between first and second embodiments are that the number of enclosed space is increased from one to more than one (e.g., A2, A3, . . . , An wherein A2 and A3 are shown). Coolant flow controller 362 and solenoid-controlled valve SV2 are located on the path of coolant flow of enclosed space A2. Coolant flow controller 363 and solenoid-controlled valve SV3 are located on the path of coolant flow of enclosed space A3. Solenoid-controlled valve SV2 and throttle valve K2 are located on the path of coolant flow of enclosed space A2. Solenoid-controlled valve SV3 and throttle valve K3 are located on the path of coolant flow of enclosed space A3. Controls M1 and M2 are controlled by CPU 30 for controlling the corresponding enclosed spaces A2 and A3 respectively, i.e., CPU 30 may control the activation of sensors C2, D2, C3, D3, E2, and E3, the on-off of solenoid-controlled valves SV2 and SV3, and the operations of fan motors 382 and 383. Compressor 31 and defrost bypass valves SV-b and SV-c are also controlled by CPU 30. Control panels F2 and F3 are operable to set indoor temperature Tas and other functionalities in enclosed spaces A2 and A3 respectively. Solenoid-controlled valves SV2 and SV3 are commanded to control the coolant flow into respective enclosed spaces A2 and A3. The relationship among enclosed spaces A2 and A3, controls M1 and M2, throttle valves K2 and K3, and solenoid-controlled valves SV2 and SV3 is as follows: Control M1, solenoid-controlled valve SV2, and throttle valve K2 are located in enclosed space A2; and control M2, solenoid-controlled valve SV3, and throttle valve K3 are located in enclosed space A3. Ambient temperatures of enclosed spaces A2 and A3 (i.e., sensed values) are Ta2 and Ta3 respectively. The sensed values thereof are Tas2 and Tas3 respectively. The coil temperatures in enclosed spaces A2 and A3 are Tie2 and Tie3 respectively in air conditioning cycle with a default value Ties. The coil temperatures in enclosed spaces A2 and A3 are Tic2 and Tic3 respectively in heating cycle with a default value Tics. The coil temperatures outside enclosed spaces A2 and A3 are Toe and Toc respectively with default values Toes and Tocs. The ice forming temperatures in enclosed spaces A2 and A3 in air conditioning cycle (i.e., sensed values) are Tei2 and Tei3 respectively with a default value Teis. The thermal storage temperatures in enclosed spaces A2 and A3 in heating cycle (i.e., sensed values) are Teh2 and Teh3 respectively with a default value Teih. The corresponding relationship between sensed values and default values of respective enclosed spaces is as follows:
A: Ta is corresponding to Tas, Tie is corresponding to Ties, Tic is corresponding to Tics, Tei is corresponding to Teis, and Teh is corresponding to Tehs; [0032]
A[0033] 2: Ta2 is corresponding to Tas2, Tie2 is corresponding to Ties, Tic2 is corresponding to Tics, Tei2 is corresponding to Teis, and Teh2 is corresponding to Tehs; and
A[0034] 3: Ta3 is corresponding to Tas3, Tie3 is corresponding to Ties, Tic3 is corresponding to Tics, Tei3 is corresponding to Teis, and Teh3 is corresponding to Tehs.
Referring to FIGS. 6 and 7, there is shown a third preferred embodiment of air conditioner/[0035] heater 4 constructed in accordance with the invention. The air conditioner/heater 4 is activated to air condition/heat a single room (i.e., one-to-one). Similar to above embodiments, air conditioner/heater 4 comprises a compressor 41, a heat exchanger 43, a fan motor 44, a filter 45, and a coolant flow controller 46 (all above components are installed outside an enclosed space A4). Air conditioner/heater 4 further comprises a heat exchanger 47, a fan motor 48, a thermal storage 49, a solenoid-controlled valve SV4, and a throttle valve K4 (all are installed indoors). Air conditioner/heater 4 is controlled by a CPU 40 through associated components such as a directional-control valve 42, a plurality of sensors B3, C4, D4, E4, and H1, and a control panel F4. The difference between this and above first and second embodiments is that a heat recovery unit 41 is provided between the outlet of compressor 41 and switch valve 42 for recovering heat from exhaust of the air conditioner/heater 4. The recovered heat may be employed to make hot water or other purposes. This can more effectively utilize energy for obtaining a higher thermal efficiency. As shown, above sensor H1 can sense the hot water temperature of heat recovery unit 411 (i.e., sensed values Tf).
Referring to FIGS. 8 and 9, there is shown a fourth preferred embodiment of air conditioner/[0036] heater 5 constructed in accordance with the invention. The air conditioner/heater 5 is activated to air condition/heat a plurality of rooms (i.e., one-to-many). Similar to third embodiment, air conditioner/heater 5 comprises a compressor 51, a heat recovery unit 511, a heat exchanger 53, a fan motor 54, a filter 55, a plurality of coolant flow controllers 561 and 562, and a plurality of defrost bypass valves SV-e and SV-f (all above components are installed outside enclosed spaces A5 and A6). Air conditioner/heater 5 further comprises a plurality of heat exchangers 571 and 572, a plurality of fan motors 581 and 582, a plurality of solenoid-controlled valves SV5 and SV6, and a plurality of throttle valves K5 and K6 (all are installed in the enclosed spaces A5 and A6 respectively). The air conditioner/heater 5 is controlled by a CPU 50 through associated components such as a directional-control valve 52, a switch valve 52, a plurality of controls M3 and M4, a plurality of sensors B4, C5, C6, D5, D6, E5, and E6, and a plurality of control panels F5 and F6. This can also more effectively utilize energy for obtaining a higher thermal efficiency. As shown, an additional sensor H2 can sense the hot water temperature of heat recovery unit 511 (i.e., sensed values Tf). The corresponding relationship between sensed values and default values of respective enclosed spaces is the same as the second embodiment. Thus, a detailed description thereof is omitted herein for the sake of brevity.
Referring to FIGS. [0037] 10 to 15 in conjunction with FIGS. 16 to 25, flow charts of the control processes of first to fourth embodiments of the invention will now be described in detail. In FIG. 10 sensed values Ta, Tie, Tic, Toe, Toc, Tei, Teh, and Tf obtained from sensors B1, B2, B3, C1, C2, C3, D1, D2, D3, E1, E2, E3, H1, and H2 are sent to CPU 20 (30, 40, or 50) for comparison with default values Tas, Tics, Toes, Tocs, Teis, Tehs, and Tfs. Then a determination is made whether it is in air conditioning or heating cycle. If air conditioner/heater is neither in air conditioning nor in heating cycle, process goes to a next step to determine whether Tf<Tfs. If the result is positive, the process is in a hot water making cycle and the process jumps to F (FIG. 15), otherwise stop the indoor fan motor 28, 382, 383, 48, 581, or 582 and process loops back to the beginning. If air conditioner/heater is in either air conditioning or heating cycle, the process goes to a next step for determining whether directional-control valve 22 (32, 42, or 52) has switched to air conditioning cycle. If yes, process goes to air conditioning cycle, otherwise process goes to heating cycle. Next, a determination is made whether process is one-to-one or one-to-many with respect to respective cycles (i.e., air conditioning cycle and heating cycle). Then process goes to A, B, C, or D corresponding to one of FIGS. 11 to 14 based on the result of above determination.
Following is a detailed description of hot water making operation of the invention (see FIG. 15). First, activate [0038] outdoor fan motor 24, 34, 44, or 54 and compressor 21, 31, 41, or 51 and close defrost bypass valve SV-a, SV-b, SV-c, SV-d, SV-e, or SV-f. If Toe>Toes, outdoor fan motor 24, 34, 44, or 54 operates in lowest speed; otherwise, if Toes−X<Toe<Toes, the rotating speed of outdoor fan motor 24, 34, 44, or 54 is inversely proportional to Toe; otherwise, if Toe<Toes−X, outdoor fan motor 24, 34, 44, or 54 operates in full speed; otherwise, the process loops back to the beginning of F. Then close defrost bypass valve SV-a, SV-b, SV-c, SV-d, SV-e, or SV-f. If Toe<Toes−X2, close defrost bypass valve SV-a, SV-b, SV-c, SV-d, SV-e, or SV-f for defrosting; otherwise continue to close defrost bypass valve SV-a, SV-b, SV-c, SV-d, SV-e, or SV-f. If Toe>Toes+X2, close defrost bypass valve SV-a, SV-b, SV-c, SV-d, SV-e, or SV-f for stopping the defrost cycle. If Tf>Tfs+X, outdoor fan motor 24, 34, 44, or 54 and compressor 21, 31, 41, or 51 stop. The process loops back to G (FIG. 10).
Following is a detailed description of air conditioning operation of the invention wherein [0039] switch valve 22, 32, 42, or 52 has switched to air conditioning cycle.
One-to-one operation mode (see FIGS. 2, 6 and [0040] 11):
If ambient temperature of enclosed space A[0041] 1 (or A4) (i.e., sensed value Ta) is larger than Tas (i.e., Ta>Tas), indoor fan motor 28 or 48 starts to operate; otherwise the process jumps to last step in FIG. 11. If Ta>Tas+X, indoor fan motor 28 or 48 operates in full speed; otherwise, if Tas<Ta<Tas+X, the rotating speed of indoor fan motor 28 or 48 is proportional to Ta (as indicated by line L1-L2 in FIG. 16); otherwise, if Ta<Tas, the rotating speed of indoor fan motor 28 or 48 operates in lowest speed. Then the process determines whether Tei is less than or equal to Teis (i.e., Tei≦Teis). If yes, it means that there is enough ice in thermal storage 29 or 49 for air conditioning the enclosed space A1 or A4. Hence, solenoid-controlled valve SV2 or SV4 is turned on to cause the air conditioner/heater to enter into melting cycle, compressor 21 or 41 stops, outdoor heat exchanger 23 or 43 stops, and the process loops back to determine whether Tei is less than or equal to Teis (i.e., Tei≦Teis). The process determines whether Tei is larger than Teis (i.e., Tei>Teis). If not, the process goes back to determine whether Tel≦Teis. If yes, it means that there is not enough ice in thermal storage 29 or 49 for air conditioning the enclosed space A1 or A4. Hence, solenoid-controlled valve SV2 or SV4 is turned on to cause the air conditioner/heater to enter into air conditioning cycle, and outdoor fan motor 24 or 44 starts to operate (see FIGS. 22 to 25). If Toc>Tocs, outdoor fan motor 24 or 44 operates in full speed; otherwise, if Tocs−X<Toc<Tocs, the rotating speed of outdoor fan motor 24 or 44 is proportional to Toc (as indicated by line L3-L4 in FIG. 17); otherwise, if Toc<Tocs−X, outdoor fan motor 24 or 44 operates in lowest speed (or even stops); otherwise, the process goes back to determine whether Tel≦Teis. Compressor 21 starts to operate. If Tie<Ties−X (i.e., coil temperature of indoor heat exchanger is less than default offset Ties minus default offset X), solenoid-controlled valve SV2 or SV4 is closed (OFF) and the thermal storage 29 or 49 enters into ice forming cycle. If Ta<Tas−X and Tei<Teis−X (i.e., thermal storage 29 or 49 has finished the ice forming task), Tie<Ties−X, or Toc>Tocs+X, indoor fan motor 28 or 48 operates in lowest speed (or even stops), outdoor fan motor 24 or 44 stops, and compressor 21 or 41 stops (OFF).
One-to-many operation mode (see FIGS. 4, 8, and [0042] 12).
(A) In any enclosed space An (where n is [0043] 2, 3, . . . , or n), if ambient temperature (i.e., sensed value Ta) is larger than Tas (i.e., Ta>Tas), indoor fan motor 382, 383, 581, or 582 starts to operate; otherwise the process jumps to last step in FIG. 12. If Ta>Tas+X, indoor fan motor 382, 383, 581, or 582 operates in full speed; otherwise, if Tas<Ta<Tas+X, the rotating speed of indoor fan motor 382, 383, 581, or 582 is proportional to Ta (as indicated by line L1-L2 in FIG. 16); otherwise, if Ta<Tas, the rotating speed of indoor fan motor 382, 383, 581, or 582 operates in lowest speed. Then the process determines whether Tei is less than or equal to Teis (i.e., Tei≦Teis). If yes, it means that there is enough ice in thermal storage 29 or 49 for air conditioning the enclosed space A2 or A3. Hence, solenoid-controlled valve SV2, SV3, SV5, or SV6 is turned on to cause the air conditioner/heater to enter into melting cycle, compressor 31 or 51 stops, outdoor fan motor 34 or 54 stops, and the process loops back to determine whether Tei is less than or equal to Teis (i.e., Tei<Teis). The process determines whether Tei is larger than Teis (i.e., Tei>Teis). If not, the process goes back to determine whether Tel≦Teis. If yes, outdoor fan motor 34 or 54 starts to operate and solenoid-controlled valve SV2, SV3, SV5, or SV6 is turned on. If Toc>Tocs when outdoor fan motor 34 operates, outdoor fan motor 34 and 54 operate in full speed; otherwise, if Tocs−X<Toc<Tocs, the rotating speed of outdoor fan motor 34 is proportional to Toc (as indicated by line L3-L4 in FIG. 17); otherwise, if Toc<Tocs−X, outdoor fan motor 34 and 54 operate in lowest speed (or even stop); otherwise, the process goes back to determine whether Tel≦Teis. If one of indoor fan motors 382, 383, 581, and 582 operates and outdoor fan motors 34 and 54 operate, compressor 31 and 51 begin to operate. If Tie<Ties−X, solenoid-controlled valves SV2, SV3, SV5, and DV6 are closed and thermal storages 392, 393, 591, and 592 enter into ice forming cycle; otherwise, the process goes back to determine whether Tel≦Teis. If Ta<Tas−X and Tei<Teis−X (i.e., thermal storages 392, 393, 591, and 592 have finished the ice forming task) or Tie≦Ties−X, solenoid-controlled valves SV2, SV3, SV5, and SV6 are closed; otherwise, the process loops back to determine whether Tei is less than or equal to Teis (i.e., Tei≦Teis). If Toc>Tocs+X or all solenoid-controlled valves SV2, SV3, SV5, and SV6 are closed, outdoor fan motor 34 and 54 stop and compressors 31 and 51 stop (OFF).
Following is a detailed description of heating operation of the invention wherein [0044] switch valve 22, 32, 42, or 52 has switched to heating cycle.
One-to-one operation mode (see FIGS. 3, 7 and [0045] 13):
If ambient temperature of enclosed space A[0046] 1 or A4 (i.e., sensed value Ta) is smaller than Tas (i.e., Ta<Tas), the coil temperature of indoor heat exchanger (used as evaporator) 27 or 47 (i.e., sensed value Tic) is smaller than the subtraction of default offset X from default value Tics (i.e., Tic<Tics−X), and the coil temperature of outdoor heat exchanger (used as condenser) 23 or 43 (i.e., sensed value Toc) is larger than the sum of default value Toes and a first default offset X (i.e., Toe>Toes+X1), in case (a) indoor fan motor 28 or 48 starts to operate. If Tic<Tics−X, indoor fan motor 28 or 48 operates in lowest speed (or even stops). If Tics−X<Tic<Tics, the rotating speed of indoor fan motor 28 or 48 is proportional to Tic (as represented by line L5-L6 in FIG. 18). If Tic>Tics, indoor fan motor 28 or 48 operates in full speed; and in case (b) outdoor fan motor 24 or 44 starts to operate. If Toe>Toes, outdoor fan motor 24 or 44 operates in lowest speed. If Toes−X<Toe<Toes, the rotating speed of outdoor fan motor 24 or 44 is inversely proportional to Toe (as represented by line L7-L8 in FIG. 19). If Toe<Toes−X, outdoor fan motor 24 operates in full speed. Then compressor 21 or 41 begins to operate as fan motors 24, 44, 28, and 48 operate (FIGS. 20 to 25), while solenoid-controlled valves SV1 and SV4 are closed (ON) and defrost bypass valves SV-a and SV-d are off. If Toe<Toes−X2 (where X2 is a second default offset), defrost bypass valves SV-a and SV-d are turned on (ON) to enter into defrost cycle (as represented by dashed line X2-X2 in FIG. 25). If Tic>Tics, solenoid-controlled valves SV1 and SV4 are turned on (ON). If Tic<Tics−X, solenoid-controlled valves SV1 and SV4 are turned off (OFF). If Toe>Toes+X2, defrost bypass valves SV-a and SV-d are off. If Ta>Tas+X, Tic>Tics+X, or Toe<Toes−X1, indoor fan motor 28 and 48 operate in lowest speed (or even stop), outdoor fan motors 24 and 44 stop, and compressors 21 and 41 stop (OFF).
One-to-many operation mode (see FIGS. 5, 9, and [0047] 14):
In any enclosed space An (where n is [0048] 2, 3, . . . , or n), if ambient temperature (i.e., sensed value Ta) is smaller than Tas (i.e., Ta<Tas), the corresponding indoor coil temperature (sensed value Tic) is smaller than the subtraction of default offset X from default value Tics (i.e., Tic<Tics−X), and Toe>Toes+X1, in case (a) indoor fan motor 382, 383, 581, or 582 corresponding to enclosed space A2 (or A3) starts to operate. If Tic<Tics−X, indoor fan motor 382, 383, 581, or 582 operates in lowest speed (or even stops). If Tics−X<Tic<Tics, the rotating speed of indoor fan motor 382, 383, 581, or 582 is proportional to Tic (as represented by line L5-L6 in FIG. 18). If Tic>Tics, indoor fan motor 382, 383, 581, or 582 operates in full speed; and in case (b) outdoor fan motor 34 or 54 starts to operate. If Toe>Toes, outdoor fan motor 34 or 54 operates in lowest speed. If Toes−X<Toe<Toes, the rotating speed of outdoor fan motor 34 or 54 is inversely proportional to Toe (as represented by line L7-L8 in FIG. 19). If Toe<Toes−X, outdoor fan motor 34 or 54 operates in full speed. Compressors 31 and 51 begin to operate as one of indoor fan motors 382, 383, 581, and 582 operates and outdoor fan motors 34 and 54 operate (FIGS. 20 to 25), while defrost bypass valves SV2, SV3, SV 5, and SV6 are turned on (ON) and defrost bypass valves SV-b, SV-c, SV-e, and SV-f are off. If Toe<Toes X2, defrost bypass valve SV-b is turned on (ON) to enter into defrost cycle (as represented by dashed line X2-X2 in FIG. 25). If Tic>Tics, the corresponding solenoid-controlled valve SV2, SV3, SV5, or SV 6 is turned on. If Tic<Tics−X, the corresponding solenoid-controlled valve SV2, SV3, SV5, and SV 6 is turned off. If Toe>Toes+X2, defrost bypass valve SV-b is turned off. If Ta>Tas+X or Tic>Tics+X, the corresponding solenoid-controlled valve SV2, SV3, SV5, or SV6 is turned off. If Toe<Toes−X1, or all solenoid-controlled valves SV2, SV3, SV5, and SV6 are turned off, outdoor fan motors 34 and 54 and compressors 31 and 51 stop (OFF).
In brief, the air conditioner/heater of the invention can accumulate heat for future off-peak use. Further, the air conditioner/heater can automatically operate in one of air conditioning, heating, and hot water supplying modes by coil temperatures of indoor and outdoor heat exchangers. With this automatic switching of operation mode, the operation of the air conditioner/heater is maintained at an optimum, resulting in an increase of operational efficiency as well as energy saving. [0049]
While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims. [0050]

Claims

What is claimed is:

1. A process for controlling an air conditioner/heater by thermal storage, said process comprising the steps of:

1) sending ambient temperature of at least one enclosed space sensed by a plurality of sensors to a central processing unit (CPU) for comparison with a predetermined value;

2) switching to operate in one of air conditioning, heating, and hot water supplying modes; and

3) if switching to said air conditioning mode and said temperature of said thermal storage is less than or equal to said predetermined value, a compressor is turned off, an outdoor fan motor is turned off, and a solenoid-controlled valve is turned on to cause said process to enter into a melting cycle.

2. The process of claim 1, wherein in said step 3) if switching to said air conditioning mode and said temperature of said thermal storage is less than said predetermined value minus a first predetermined offset, said solenoid-controlled valve is turned off to cause said process to enter into a ice forming cycle.

3. The process of claim 1, wherein if coil temperature of an outdoor heat exchanger is less than said predetermined value minus a second predetermined offset, a defrost bypass valve is turned on to cause said process to enter into a defrost cycle.