CN102679494A - Control method of low temperature refrigeration of rooftop air conditioning unit - Google Patents
Control method of low temperature refrigeration of rooftop air conditioning unit Download PDFInfo
- Publication number
- CN102679494A CN102679494A CN2012101344657A CN201210134465A CN102679494A CN 102679494 A CN102679494 A CN 102679494A CN 2012101344657 A CN2012101344657 A CN 2012101344657A CN 201210134465 A CN201210134465 A CN 201210134465A CN 102679494 A CN102679494 A CN 102679494A
- Authority
- CN
- China
- Prior art keywords
- value
- mechanical pressure
- pressure switches
- blower fan
- unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Abstract
The invention discloses a control method of low temperature refrigeration of a rooftop air conditioning unit. The method includes the steps that a first mechanical pressure switch with an off value P1 and an on value P2 is additionally arranged on an exhaust pipe; a second mechanical pressure switch with an off value P3 and an on value P4 is additionally arranged on an air returning pipe; the unit performs refrigeration operation, and two fans operate simultaneously when a exhaust pressure value is larger than or equal to P2; when the exhaust pressure value is equal to or smaller than P1, the first mechanical pressure switch is off, and a first fan stops the service; when an air returning pressure value is equal to or smaller than P3, the second mechanical pressure switch is off, and an indoor fan stops the service; when the air returning pressure value is equal to or larger than P4, the second mechanical pressure switch is on, an alternating current contactor of a second fan pulls in, and the second fan operates alone. According to the control method of the low temperature refrigeration of the rooftop air conditioning unit, refrigerants which are not evaporated completely can be prevented from entering and damaging a compressor during the low temperature refrigeration operation.
Description
Technical field:
The present invention relates to field of air conditioning, is a kind of three-phase blower fan roof Top Air-conditioning Unit cryogenic refrigeration control method specifically.
Background technology:
The prior roofs air-conditioning is because the refrigerating capacity that the field of employment requires is bigger; General indoor and outdoor blower motor all adopts three phase electric machine to drive blower fan, and it basic composition is compressor, condenser, outdoor twin shaft flow fan, throttling arrangement, evaporimeter and indoor centrifugal blower and forms.During refrigerating operaton, the air-conditioning unit is according to refrigeration principle, through compressor work with heat from indoor transfer to outdoor.When the roof air-conditioning unit kind of refrigeration cycle of prior art was normally moved, outdoor twin shaft flow fan, indoor centrifugal blower, compressor be normally operation all.
At present in actual use for the roof air-conditioning, generally be when outdoor temperature is high, require air-conditioning to carry out refrigerating operaton, when outdoor temperature is low, require heating operation.But some special place is low even when being lower than 0 ° when outdoor temperature, still requires the air-conditioning unit to carry out refrigerating operaton.Such as big places of special heat dissipation capacity such as machine room, forges, it promptly requires indoor and outdoor separately, requires indoor environment temperature to remain on about 18～30 ° again; Because in the time of indoor machine or equipment operation; Constantly dispelling the heat in the capital, causes indoor temperature constantly to raise, thereby influence the service life of machine or influence work efficiency of workers; This just requires the air conditioner group under the low situation of environment temperature, also need carry out refrigerating operaton.And the roof air-conditioning of prior art is under low temperature environment, low owing to environment temperature during the air-conditioning unit operation; The high-temperature gas pressure that causes compressor to be discharged is on the low side, pass through throttling again after, the pressure of cold-producing medium is lower; The evaporating pressure evaporating temperature that causes on the low side is far below 0 ° after often getting into evaporimeter, and when evaporating temperature is lower than 0 °, will make the condensate on the evaporimeter, slowly becomes frost; Thereby reduce room air and pass through evaporimeter; Cause cold-producing medium fully heat exchange flash to gas fully, band liquid gets into compressor, makes compressor carry out hydraulic pressure and contracts and cause the too fast damage of compressor the most at last.
Summary of the invention:
The objective of the invention is to prior art not enoughly, provide a kind of cold-producing medium that does not evaporate fully that under low temperature environment, can effectively prevent during refrigerating operaton to get into compressor and damage the three-phase blower fan roof Top Air-conditioning Unit cryogenic refrigeration control method of compressor.
In order to solve the problems of the technologies described above, the technical solution that the present invention adopts is: the control method of a kind of roof air-conditioning unit (three-phase blower fan) cryogenic refrigeration, it comprises the steps:
(1) on the blast pipe of unit, increasing a cut off value is P
1, the connection value is P
2First mechanical pressure switches, terminals of said first mechanical pressure switches are connected on the L1 line, connect on the N line after an end of another terminals and the first blower fan A.C. contactor KM1 coil is connected;
(2) on the muffler of the evaporator outlet of unit, increasing a cut off value is P
3, the connection value is P
4Second mechanical pressure switches, terminals of said second mechanical pressure switches are connected on the L1 line, connect on the N line after an end of another terminals and the second blower fan A.C. contactor KM2 coil is connected;
(3) unit carries out refrigerating operaton, and mechanical pressure switches is monitored the pressure on the blast pipe in real time, when exhaust pressure value more than or equal to P
2The time, two blower fans (first blower fan, second blower fan) move simultaneously; When exhaust pressure value is equal to or less than P
1The time, said first mechanical pressure switches is broken off, and the first blower fan A.C. contactor breaks off, first blower fan is out of service; When the back pressure value is equal to or less than P
3The time, said second mechanical pressure switches is broken off, and the second blower fan A.C. contactor breaks off then that outdoor fan shuts down; When the back pressure value is equal to or greater than P
4The time, said second mechanical pressure switches is closed, the second blower fan A.C. contactor adhesive, the second blower fan isolated operation.
Adopt above method, roof Top Air-conditioning Unit cryogenic refrigeration control method of the present invention compared with prior art has following remarkable advantage and beneficial effect:
When the air-conditioning unit carries out cold operation, when exhaust pressure value is equal to or less than P
1The time, said first mechanical pressure switches is broken off, and the first blower fan A.C. contactor breaks off, first blower fan is out of service, with the heat exchange of minimizing with outdoor air, thus the operating pressure of raising unit, and then improve evaporating pressure; When environment temperature further reduces, when the back pressure value is equal to or less than P
3The time, said second mechanical pressure switches is broken off, and the second blower fan A.C. contactor breaks off then that outdoor fan shuts down, thereby stops the heat exchange of outdoor air; When outdoor fan shut down, the back pressure value was equal to or greater than P
4The time, said second mechanical pressure switches is closed, and the second blower fan A.C. contactor is inhaled and the second blower fan isolated operation, and unit works on; When the environment temperature rising, the atmospheric pressure value is more than or equal to P
2The time; Said first mechanical pressure switches is closed; Two blower fans move simultaneously; Unit recovers normal operation: the present invention controls the start and stop of blower fan through the force value of unit; The evaporating pressure of control air-conditioning unit contracts, causes the most at last the phenomenon of the too fast damage of compressor to occur thereby avoid causing carrying out in the cold-producing medium band liquid entering compressor under the situation such as cold-producing medium evaporates not exclusively, evaporimeter frosting hydraulic pressure because of evaporating pressure is low excessively in evaporimeter, has improved the cryogenic refrigeration operation conditions of air-conditioning unit.
And method of the present invention is easy easily, and is safe and reliable, need not change the controller of unit, only needs to increase by two mechanical pressure switches and gets final product.
As improvement, the force value of said first mechanical pressure switches is P
1And P
2Be 0.9MPa～1.4MPa, and P
1＜P
2The force value of said second mechanical pressure switches is P
3And P
4Be 0.15MPa～0.4Mpa, and P
3＜P
4Prove through repetition test, can not be with the liquid operation by reasonable assurance unit when being in this pressure limit;
As further improvement, the cut off value P of said first mechanical pressure switches
1Be 1.0MPa, closing value P
2Be 1.3MPa; The cut off value P of said second mechanical pressure switches
3Be 0.25MPa, closing value P
4Be 0.4MPa, prove, can guarantee well when being in this pressure limit that unit is not with liquid operation through repetition test;
As further improving again; Unit or multi-compressor unit for double compressor system; Increase said first, second mechanical pressure switches (promptly all increasing mechanical pressure switches) in the same position of the other system of unit and also be cascaded the mechanical pressure switches line of said same position, control as long as there is a system mechanics pressure switch to move all to blower fan start and stop in the same position of the system of single compressor.
As improvement, for heat pump air conditioner unit with heat-production functions, cross valve commutation signal line be connected on the L1 line and the first blower fan A.C. contactor KM1 after said first mechanical pressure switches is parallelly connected; Said second mechanical pressure switches is placed on evaporator outlet to the muffler of cross valve import, when unit carries out heating operation, cross valve get electric after, KM1 need not detect the state of said first mechanical pressure switches with direct adhesive; During heating operation; Owing to commutate, evaporator outlet is a high-pressure side to cross valve import (evaporimeter of refrigerating operaton), and said second mechanical pressure switches is in closed position; Therefore when carrying out heating operation; Two outdoor fans all move (front discuss be the single cooler group, here for the unit of band heat pump functional, when carrying out heating operation; Air-conditioning will equally with common unit move, and that is to say has increased mechanical pressure switches the unit of cryogenic refrigeration function is arranged, do not influence normal heating operation).
Description of drawings:
Fig. 1 is the system schematic of patent roof Top Air-conditioning Unit cryogenic refrigeration control method of the present invention.
Fig. 2 is the electrical wiring sketch map of the control blower fan start and stop of patent roof Top Air-conditioning Unit cryogenic refrigeration control method of the present invention.
As shown in Figure 1: 1, compressor, 2, blast pipe, 3, first mechanical pressure switches; 4, four-way change-over valve, 5, outdoor heat exchanger, 6 outdoor aerofoil fans; 7, throttling arrangement, 8 indoor centrifugal blowers, 9, indoor heat exchanger; 10, second mechanical pressure switches, 11, muffler, 12, gas-liquid separator; 13, the first blower fans, 14. second blower fans, 15. low tension switches, 16. high-voltage switch gears.
The specific embodiment:
Below in conjunction with accompanying drawing and specific embodiment, patent of invention roof Top Air-conditioning Unit cryogenic refrigeration control method is explained further details, but the present invention is not limited only to following specific embodiment: shown in accompanying drawing 1; The air conditioner group system sketch map of roof Top Air-conditioning Unit cryogenic refrigeration control method of the present invention, wherein compressor 1, blast pipe 2; Four-way change-over valve 4, outdoor heat exchanger 5, outdoor aerofoil fan 6; Throttling arrangement 7, indoor centrifugal blower 8, indoor heat exchanger 9; Muffler 11, gas-liquid separator 12; , first blower fan, 13, the second blower fans 14, low tension switch 15, high-voltage switch gear 16 is formed the conventional roof of industry air-conditioning unit, is not described in detail in this; With above-mentioned accompanying drawing 1 said machine set system figure is example, and the control method that the present invention adopts is following: (concrete electrical wiring sketch map is seen Fig. 2)
(1) on the blast pipe 2 of unit, increasing a cut off value is P
1, the connection value is P
2First mechanical pressure switches 3, P
1, P
2Numerical value can be 0.9MPa～1.4MPa, this embodiment P
1Be 1.0MPa, P
2Be 1.3MPa; Terminals of said first mechanical pressure switches are connected on the L1 line, connect on the N line after another terminals and the series connection of the first blower fan A.C. contactor KM1 coil; And, with after said first mechanical pressure switches 3 is parallelly connected, be connected on cross valve commutation signal line on the N line with the first blower fan A.C. contactor KM1 again for source pump;
(2) on the muffler 11 of the evaporator outlet of unit, increasing a cut off value is P
3, the connection value is P
4Second mechanical pressure switches 10, P
3, P
4Numerical value can be 0.15MPa～0.4MPa, this embodiment P
3Be 0.25MPa, P
4Be 0.4MPa; Terminals of said second mechanical pressure switches are connected on the L1 line, are connected on the N line after the coil series connection of the A.C. contactor KM2 of another terminals and second blower fan 14;
When (3) the air-conditioning unit carries out refrigerating operaton; When outdoor temperature is low when being equal to or less than 1.0MPa than exhaust pressure value; Said first mechanical pressure switches 3 is broken off, and the A.C. contactor of first blower fan breaks off, first blower fan 13 is out of service, and unit carries out single fan operation; When environment temperature further reduces, when the back pressure value was equal to or less than 0.25MPa, said second mechanical pressure switches 10 was broken off, and second blower fan, 14 A.C. contactors break off, and the unit outdoor fan all shuts down; After outdoor fan shuts down, when the back pressure value is equal to or greater than 0.4MPa, said second mechanical pressure switches, 10 closures, the 14 A.C. contactor adhesives of second blower fan, unit recovers isolated operation; When environment temperature raises; The atmospheric pressure value is during more than or equal to 1.3MPa; Said mechanical pressure switches 3 closures; Two blower fans move simultaneously, and unit recovers normal operation: the present invention controls the start and stop of blower fan, the evaporating pressure of control air-conditioning unit through the force value of unit; Contract, cause the most at last the phenomenon of the too fast damage of compressor to occur thereby avoid causing carrying out hydraulic pressure in the cold-producing medium band liquid entering compressor under the situation such as cold-producing medium evaporation in evaporation is incomplete, evaporimeter frosting, improved the cryogenic refrigeration operation conditions of air-conditioning unit because of evaporating pressure is low excessively.
The present invention is on the basis of conventional air-conditioning; Only need to increase the low cost of two mechanical pressure switches; Need not develop again controller; Through control rational range of pressure values can make the air-conditioning unit can be under low temperature environment safety carry out refrigerating operaton, method is very easy, with low cost.
Claims (5)
1. roof Top Air-conditioning Unit cryogenic refrigeration control method, it is characterized in that: it comprises the steps:
(1) going up cut off value of increase at the blast pipe (2) of unit is P
1, the connection value is P
2First mechanical pressure switches (3), terminals of said first mechanical pressure switches (3) are connected on the L1 line, connect on the N line after an end of another terminals and first blower fan (13) A.C. contactor KM1 coil is connected;
(2) go up at the muffler (11) of the evaporator outlet of unit that to increase a cut off value be P
3, the connection value is P
4Second mechanical pressure switches (10), terminals of said second mechanical pressure switches (10) are connected on the L1 line, connect on the N line after an end of another terminals and second blower fan (14) A.C. contactor KM2 coil is connected;
(3) unit carries out refrigerating operaton, and mechanical pressure switches is monitored the pressure on the blast pipe in real time, and when exhaust pressure value during more than or equal to P2, two blower fans move simultaneously; When exhaust pressure value is equal to or less than P
1The time, said first mechanical pressure switches (3) is broken off, and first blower fan (13) A.C. contactor breaks off, first blower fan (13) is out of service; When the back pressure value is equal to or less than P
3The time, said second mechanical pressure switches (10) is broken off, and second blower fan (14) A.C. contactor breaks off then that outdoor fan shuts down; When the back pressure value is equal to or greater than P
4The time, said second mechanical pressure switches (10) closure, second blower fan (14) A.C. contactor adhesive, the second blower fan isolated operation.
2. roof Top Air-conditioning Unit cryogenic refrigeration control method according to claim 1 is characterized in that: the cut off value P of said first mechanical pressure switches (3)
1, connection value P
2Be 0.9MPa～1.4MPa, and P
1＜P
2The cut off value P of said second mechanical pressure switches (10)
3, connection value P
4Be 0.15MPa～0.4Mpa, and P
3＜P
4
3. roof Top Air-conditioning Unit cryogenic refrigeration control method according to claim 2 is characterized in that: the cut off value P of said first mechanical pressure switches (3)
1Be 1.0MPa, closing value P
2Be 1.3MPa, the cut off value P of said second mechanical pressure switches (10)
3Be 0.25MPa, closing value P
4Be 0.4Mpa.
4. roof Top Air-conditioning Unit cryogenic refrigeration control method according to claim 1; It is characterized in that: for the unit and the multi-compressor unit of double compressor system; All increase mechanical pressure switches in the same position of the system of single compressor; And be cascaded the mechanical pressure switches line of said same position, as long as have a system mechanics pressure switch action all to blower fan start and stop control.
5. roof Top Air-conditioning Unit cryogenic refrigeration control method according to claim 1; It is characterized in that: for the heat pump air conditioner unit that heat-production functions is arranged, cross valve commutation signal line be connected on L1 line and first blower fan (13) the A.C. contactor KM1 after said first mechanical pressure switches (3) is parallelly connected; Said second mechanical pressure switches (10) is placed on evaporator outlet to the muffler (11) of cross valve import.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210134465.7A CN102679494B (en) | 2012-05-03 | 2012-05-03 | Control method of low temperature refrigeration of rooftop air conditioning unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210134465.7A CN102679494B (en) | 2012-05-03 | 2012-05-03 | Control method of low temperature refrigeration of rooftop air conditioning unit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102679494A true CN102679494A (en) | 2012-09-19 |
| CN102679494B CN102679494B (en) | 2014-04-02 |
Family
ID=46811802
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210134465.7A Active CN102679494B (en) | 2012-05-03 | 2012-05-03 | Control method of low temperature refrigeration of rooftop air conditioning unit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102679494B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103398444A (en) * | 2013-07-01 | 2013-11-20 | Tcl空调器(中山)有限公司 | Air conditioner low-temperature refrigeration method and device |
| CN104833056A (en) * | 2015-05-11 | 2015-08-12 | 广东美的暖通设备有限公司 | Control method and control system for outdoor fans of air conditioner |
| CN109595850A (en) * | 2019-01-08 | 2019-04-09 | 广东美的暖通设备有限公司 | Control method and air-conditioning system |
| CN111520895A (en) * | 2020-04-29 | 2020-08-11 | 珠海格力电器股份有限公司 | Control method of condensing fan and refrigerating unit |
| CN113028574A (en) * | 2021-04-20 | 2021-06-25 | 宁波奥克斯电气股份有限公司 | Control method and control device for improving reliability of air conditioner and air conditioner |
| CN113098067A (en) * | 2021-05-08 | 2021-07-09 | 国网上海市电力公司 | Roof fan device and intelligent power generation and temperature and humidity control system thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101650064A (en) * | 2008-08-14 | 2010-02-17 | 海尔集团公司 | Low-temperature refrigeration air conditioner and wind speed control method thereof |
| CN101788214A (en) * | 2009-12-18 | 2010-07-28 | 艾默生网络能源有限公司 | Air conditioning condenser |
| CN102121741A (en) * | 2011-03-14 | 2011-07-13 | 广东美的电器股份有限公司 | Multi-connection air conditioning unit and control method thereof during small-load refrigeration running |
-
2012
- 2012-05-03 CN CN201210134465.7A patent/CN102679494B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101650064A (en) * | 2008-08-14 | 2010-02-17 | 海尔集团公司 | Low-temperature refrigeration air conditioner and wind speed control method thereof |
| CN101788214A (en) * | 2009-12-18 | 2010-07-28 | 艾默生网络能源有限公司 | Air conditioning condenser |
| CN102121741A (en) * | 2011-03-14 | 2011-07-13 | 广东美的电器股份有限公司 | Multi-connection air conditioning unit and control method thereof during small-load refrigeration running |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103398444A (en) * | 2013-07-01 | 2013-11-20 | Tcl空调器(中山)有限公司 | Air conditioner low-temperature refrigeration method and device |
| CN103398444B (en) * | 2013-07-01 | 2016-12-28 | Tcl空调器(中山)有限公司 | Air conditioner low-temperature refrigeration method and device |
| CN104833056A (en) * | 2015-05-11 | 2015-08-12 | 广东美的暖通设备有限公司 | Control method and control system for outdoor fans of air conditioner |
| CN104833056B (en) * | 2015-05-11 | 2017-10-31 | 广东美的暖通设备有限公司 | Control method and control system for the outdoor fan of air conditioner |
| CN109595850A (en) * | 2019-01-08 | 2019-04-09 | 广东美的暖通设备有限公司 | Control method and air-conditioning system |
| CN111520895A (en) * | 2020-04-29 | 2020-08-11 | 珠海格力电器股份有限公司 | Control method of condensing fan and refrigerating unit |
| CN111520895B (en) * | 2020-04-29 | 2021-04-06 | 珠海格力电器股份有限公司 | Control method of condensing fan and refrigerating unit |
| CN113028574A (en) * | 2021-04-20 | 2021-06-25 | 宁波奥克斯电气股份有限公司 | Control method and control device for improving reliability of air conditioner and air conditioner |
| CN113098067A (en) * | 2021-05-08 | 2021-07-09 | 国网上海市电力公司 | Roof fan device and intelligent power generation and temperature and humidity control system thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102679494B (en) | 2014-04-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102121741B (en) | Multi-connection air conditioning unit and control method thereof during small-load refrigeration running | |
| CN102679494B (en) | Control method of low temperature refrigeration of rooftop air conditioning unit | |
| CN103216908B (en) | Control method for outdoor fan in refrigeration of variable frequency multi-split air-conditioning unit | |
| CN202101340U (en) | Heat pump screw-type compression multi-connection central air conditioner device | |
| EP3929500B1 (en) | Air conditioner control method and device, and air conditioner | |
| CN1862130A (en) | Controlling method of safety stop of air conditioner | |
| CN203501354U (en) | Multi-connected air-conditioning system | |
| CN203131983U (en) | Refrigerating system | |
| CN105627615A (en) | Air conditioner system and control method thereof | |
| CN101008535A (en) | Low-temperature heating bypass system of air source heat pump | |
| WO2015122171A1 (en) | Air conditioning device | |
| CN104879940A (en) | Air-conditioner system and control method thereof | |
| CN204806610U (en) | Exhaust temperature controlling means and air conditioning system | |
| KR20180019042A (en) | Heat pump Refrigeration system | |
| CN111442552A (en) | Cascade type refrigerant circulating system, air conditioning equipment and control method of cascade type refrigerant circulating system | |
| CN103600748A (en) | Air-conditioning unit | |
| CN201779921U (en) | Multifunctional switch system of air conditioner and heat pump water heater | |
| CN202420014U (en) | Refrigerating system and refrigerator with same | |
| CN1532482A (en) | Defrosting method for heat pump type air conditioner | |
| CN204665731U (en) | Air-conditioning system | |
| CN101666535B (en) | Low-temperature refrigeration control device of single-phase motor in air conditioning unit | |
| CN203454295U (en) | Air conditioning system | |
| CN203731735U (en) | Screw-type air-cooled heat pump air conditioning unit | |
| CN107178932A (en) | A kind of overlength distance conveys the high energy efficiency VRF Air Conditioning System of refrigerant | |
| CN201852341U (en) | Refrigerating machine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C56 | Change in the name or address of the patentee | ||
| CP01 | Change in the name or title of a patent holder |
Address after: 315191 Zhejiang city of Ningbo province Jiangshan town Yinzhou District Mingguang Road No. 1166 Patentee after: NINGBO AUX ELECTRIC CO., LTD. Address before: 315191 Zhejiang city of Ningbo province Jiangshan town Yinzhou District Mingguang Road No. 1166 Patentee before: Ningbo AUX Electric Co., Ltd. |