CN214199278U - Air source heat pump unit with fluorine pump defrosting function - Google Patents
Air source heat pump unit with fluorine pump defrosting function Download PDFInfo
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- CN214199278U CN214199278U CN202022746607.8U CN202022746607U CN214199278U CN 214199278 U CN214199278 U CN 214199278U CN 202022746607 U CN202022746607 U CN 202022746607U CN 214199278 U CN214199278 U CN 214199278U
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Abstract
The utility model provides an air source heat pump unit with a fluorine pump defrosting function, which comprises a water heat exchanger and a first pipeline, wherein the water heat exchanger is sequentially connected with a liquid pipe two-way valve, a fluorine pump, a liquid storage device, an air heat exchanger and an air pipe two-way valve through the first pipeline; the output end of the water heat exchanger and the first pipeline between the liquid pipe two-way valves are connected with one end of a second pipeline, the other end of the second pipeline is connected between the fluorine pump and the liquid storage device, the expansion valve is connected on the second pipeline in series, the input end of the water heat exchanger and the first pipeline between the air pipe two-way valves are connected with one end of a third pipeline, the other end of the third pipeline is connected between the air pipe two-way valves and the air heat exchanger, and the compressor is connected on the third pipeline in series. The utility model discloses a take air source heat pump unit of fluorine pump defrosting function and defrosting method thereof, the surface temperature of fluorine pump defrosting wind heat exchanger is far less than the reverse circulation scheme of tradition, and the heat loss is showing and is reducing, and fluorine pump consumption is far less than the compressor moreover, and the defrosting energy consumption is little, improves comprehensive operating efficiency.
Description
Technical Field
The utility model relates to a refrigeration heat pump technical field especially relates to a take air source heat pump set of fluorine pump defrosting function.
Background
The air source heat pump cold and hot water unit needs defrosting when heating in winter, and the prior art adopts a reverse cycle defrosting method, namely, the reverse cycle defrosting method is switched to a refrigeration mode, heat is absorbed from a water system, the heat is transferred to an air heat exchanger by a compressor, so that the surface temperature of the air heat exchanger is raised, and frost is melted and removed. The defrosting method is simple and feasible, has high defrosting speed and guaranteed effect, but has the following problems:
1) the air heat exchanger heats the air to a higher temperature which can reach more than 50 ℃, and because the air temperature is low in winter, a large amount of heat is dissipated into the air, and the lower the air temperature is, the greater the heat dissipation loss is. In addition, because the phenomenon of frost-free and wrong defrosting exists in a large quantity, the heat loss caused by reverse circulation defrosting is larger.
2) During defrosting, valves are switched, fluid is reversed, and the pressure and temperature of the system are changed violently, so that impact is caused on all parts of the system. And the normal oil return of the press is not facilitated, and the whole service life of the unit is shortened. Additional noise is also generated, exacerbating the noise problem of the air source heat pump.
3) The air source heat pump cold and hot water unit can refrigerate and heat, but at present, a large number of single heating requirements exist, such as heat pump water heaters, the requirement that a centralized coal-fired boiler is transformed into an air source heat pump, and the like. In these scenes, refrigeration is not needed, and originally, switching parts such as a four-way valve and the like can be omitted, so that the system and the control are simplified. But these mechanisms must be maintained due to the reverse cycle defrost method. In fact, the four-way valve is used as a vulnerable part, so that the operation reliability is reduced, and the system operation energy efficiency is also reduced.
SUMMERY OF THE UTILITY MODEL
The utility model aims to overcome the not enough of existence among the prior art, provide a take air source heat pump set of fluorine pump defrosting function, reduce the heat loss, the defrosting energy consumption is little, improves comprehensive operating efficiency. The utility model adopts the technical proposal that:
the air source heat pump unit with the fluorine pump defrosting function is characterized by comprising a water heat exchanger and a first pipeline, wherein the water heat exchanger is sequentially connected with a liquid pipe two-way valve, a fluorine pump, a liquid storage device, an air heat exchanger and an air pipe two-way valve through the first pipeline; the output end of the water heat exchanger and the first pipeline between the liquid pipe two-way valves are connected with one end of a second pipeline, the other end of the second pipeline is connected between the fluorine pump and the liquid storage device, an expansion valve is connected on the second pipeline in series, the input end of the water heat exchanger and the first pipeline between the gas pipe two-way valves are connected with one end of a third pipeline, the other end of the third pipeline is connected between the gas pipe two-way valves and the air heat exchanger, and a compressor is connected on the third pipeline in series.
Preferably, the air source heat pump unit with the fluorine pump defrosting function further comprises a four-way valve, wherein the first end and the second end of the four-way valve are connected with the two ends of the compressor; and the fourth end of the four-way valve is connected between the air pipe two-way valve and the input end of the water heat exchanger through a fifth pipeline.
A defrosting method of an air source heat pump unit with a fluorine pump defrosting function comprises the following steps:
1) when the heat pump unit is in a defrosting state, the CO is turned off2Compressor and air heat exchanger, holding t1Time;
2) opening an air pipe two-way valve and a liquid pipe two-way valve, opening an air heat exchanger, a water heat exchanger and a fluorine pump, closing an expansion valve, starting a fluorine pump defrosting mode, and starting to calculate defrosting duration;
3) when the defrosting time reaches t2Detecting the temperature T of the refrigerant at the inlet of the air heat exchanger1And outlet refrigerant temperature T2And water temperature T at inlet of water heat exchanger3And the outlet water temperature T4And when any one of the following conditions is reached, the defrosting is finished:
duration of defrosting>tm；
T2>Tsf；
T1-T2<Tdf；
T4-T3<Tdw；
Wherein, t1，t2，tm，Tsf，Tdf，TdwAll the parameters are system variable parameters and can be adjusted at will according to actual conditions.
4) And after defrosting is finished, closing the liquid pipe two-way valve, the gas pipe two-way valve and the fluorine pump.
A defrosting method of an air source heat pump unit with a fluorine pump defrosting function comprises the following steps:
1) in a heating state, the liquid pipe two-way valve, the gas pipe two-way valve and the fluorine pump are all closed, the compressor, the expansion valve and the air heat exchanger fan are opened, the four-way valve connects the exhaust port of the compressor with the water heat exchanger, and connects the air suction port of the compressor with the air heat exchanger; when the defrosting state is reached, the compressor is closed, the air heat exchanger is closed, and t is kept1Time;
2) opening an air pipe two-way valve and a liquid pipe two-way valve, opening an air heat exchanger, a water heat exchanger and a fluorine pump, closing an expansion valve, starting a fluorine pump defrosting mode, and starting to calculate defrosting duration;
3) when the defrosting time reaches t2Detecting the temperature T of the refrigerant at the inlet of the air heat exchanger1And outlet refrigerant temperature T2And water temperature T at inlet of water heat exchanger3And the outlet water temperature T4When the defrosting time is accumulated to tmIf any one of the following conditions is met, the step 4) is carried out, otherwise, the step 5) is carried out
T2>Tsf；
T1-T2<Tdf；
T4-T3<Tdw；
Wherein, t1，t2，tm，Tsf，Tdf，TdwAll the parameters are system variable parameters and can be adjusted at will according to actual conditions.
4) After defrosting is finished, the liquid pipe two-way valve, the gas pipe two-way valve and the fluorine pump are closed;
5) the fluorine pump is closed, and liquid pipe two-way valve and trachea two-way valve are closed, and the system switches to traditional reverse cycle defrosting mode, and the defrosting aperture is adjusted to the expansion valve, and the compressor is opened, and the cross valve switches to compressor gas vent and air heat exchanger and is connected, and the compressor induction port is connected with water heat exchanger to begin the timing, if when reaching following arbitrary condition, the defrosting finishes:
duration of defrosting>tm1；
T2>Tsf1；
Wherein, tm1，Tsf1All the parameters are system variable parameters and can be adjusted at will according to actual conditions.
The utility model has the advantages that:
(1) the utility model discloses a take air source heat pump set of fluorine pump defrosting function, the surface temperature of fluorine pump defrosting wind heat exchanger is far less than the contrary circulation scheme of tradition, and the heat loss is showing and is reducing, and fluorine pump consumption is far less than the compressor moreover, and the defrosting energy consumption is little, improves comprehensive operating efficiency.
(2) The utility model discloses a take air source heat pump set defrosting process of fluorine pump defrosting function does not have the high-low pressure and switches over, has eliminated the impact and the fluid switching-over of traditional defrosting mode, has effectively protected the operation safety of each part, and the life-span has reduced the defrosting noise.
(3) For a single-heat type air source heat pump cold and hot water unit, a four-way valve can be omitted according to actual conditions, the structure is simplified, and the operation reliability and the operation efficiency are improved.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention.
Fig. 1 is a schematic view of embodiment 1 of the present invention.
Fig. 2 is a schematic view of embodiment 2 of the present invention.
FIG. 3 is a schematic diagram of temperature measurement point distribution during defrost mode.
The numbering in the figures is as follows: 1-a compressor; 2-a water heat exchanger; 3-an expansion valve; 4-wind heat exchanger; 5-liquid pipe two-way valve; 6-gas pipe two-way valve; 7-a fluorine pump; 8-a reservoir; a 9-four-way valve; 10-a first conduit; 11-a second conduit; 12-a third conduit; 13-a fourth conduit; 14-fifth pipeline.
Detailed Description
The present invention will be further described with reference to the following specific embodiments.
Example 1
As shown in fig. 1 and fig. 2, the air source heat pump unit with a fluorine pump defrosting function is provided in this embodiment, including a water heat exchanger 2 and a first pipeline 10, where the water heat exchanger 2 is sequentially connected to a liquid pipe two-way valve 5, a fluorine pump 7, a liquid reservoir 8, an air heat exchanger 4 and a gas pipe two-way valve 6 through the first pipeline 10; the output of water heat exchanger 2 with connect second pipeline 11 one end on the first pipeline between liquid pipe two-way valve 5, the second pipeline 11 other end is connected between fluorine pump 7 and reservoir 8, it has expansion valve 3 to establish ties on the second pipeline 11, the input of water heat exchanger 2 with connect third pipeline 12 one end on the first pipeline between trachea two-way valve 6, the third pipeline 12 other end is connected between trachea two-way valve 6 and air heat exchanger 4, it has compressor 1 to establish ties on third pipeline 12.
As shown in fig. 1 and 3, this embodiment is a single heating unit without cooling function, such as a heat pump water heater, and a boiler replaces a heat pump heating unit, and the unit has two operation modes: a heat pump heating mode and a fluorine pump defrost mode. In the heat pump heating mode, the fluorine pump, the liquid pipe two-way valve and the air pipe two-way valve are all closed, at the moment, the compressor, the water heat exchanger, the expansion valve, the liquid storage device and the air heat exchanger form a heat pump cycle, the water heat exchanger serves as a condenser, is connected with the tail end demand side and supplies circulating hot water for the condenser, the air heat exchanger serves as an evaporator, and along with the fact that the air heat exchanger is frosted and intensified, when defrosting is needed, the unit is switched to the fluorine pump defrosting mode. At this time, the compressor is turned off, the fan of the wind heat exchanger is turned off and maintained for a certain time, the pressure and temperature inside the unit are gradually balanced, and then, the fluorine pump, the liquid pipe two-way valve and the gas pipe two-way valve are opened, the air heat exchanger and the water heat exchanger are directly communicated through the fluorine pump to form a fluorine pump system, because the water channel of the water heat exchanger keeps circulation, the hot water heats and evaporates the refrigerant in the water heat exchanger, and enters the air heat exchanger through the air pipe two-way valve, the surface temperature of the air heat exchanger is low (not higher than 0 ℃) due to frosting, therefore, the refrigerant vapor is condensed into liquid through the air heat exchanger, is kept in the liquid storage device and is circularly sent to the water heat exchanger through the fluorine pump, the fluorine pump drives the refrigerant to circulate, the heat in the hot water is transferred to the surface of the air heat exchanger, the temperature of a frost layer is gradually increased and melted, and when the frost is melted completely, the unit switches the heating mode of the regenerative pump.
The specific defrosting method is as follows:
a defrosting method of an air source heat pump unit with a fluorine pump defrosting function comprises the following steps:
1) in the heating state, the liquid pipe two-way valve 5, the gas pipe two-way valve 6 and the fluorine pump 7 are all closed, the compressor 1, the expansion valve 3 and the air heat exchanger 4 are opened, and when the heat pump unit reaches the defrosting state, the CO is closed2 Compressor 1 and wind heat exchanger 4, holding t1Time;
2) opening an air pipe two-way valve 6 and a liquid pipe two-way valve 5, opening an air heat exchanger 4, a water heat exchanger 2 and a fluorine pump 7, closing an expansion valve 3, starting a fluorine pump defrosting mode, and starting to calculate defrosting duration;
3) when the defrosting time reaches t2Detecting the temperature T of the refrigerant at the inlet of the air heat exchanger 41And outlet refrigerant temperature T2And the water temperature T at the inlet of the water heat exchanger 23And the outlet water temperature T4And when any one of the following conditions is reached, the defrosting is finished:
duration of defrosting>tm；
T2>Tsf；
T1-T2<Tdf；
T4-T3<Tdw；
Wherein, t1，t2，tm，Tsf，Tdf，TdwAll the parameters are system variable parameters and can be adjusted at will according to actual conditions.
4) And after defrosting is finished, the liquid pipe two-way valve 5, the gas pipe two-way valve 6 and the fluorine pump 7 are closed.
Example 2
As shown in fig. 2 and fig. 3, the air source heat pump unit with a fluorine pump defrosting function in this embodiment includes a water heat exchanger 2 and a first pipeline 10, where the water heat exchanger 2 is sequentially connected to a liquid pipe two-way valve 5, a fluorine pump 7, a liquid reservoir 8, an air heat exchanger 4, and a gas pipe two-way valve 6 through the first pipeline 10; the output of water heat exchanger 2 with connect second pipeline 11 one end on the first pipeline between liquid pipe two-way valve 5, the second pipeline 11 other end is connected between fluorine pump 7 and reservoir 8, it has expansion valve 3 to establish ties on the second pipeline 11, the input of water heat exchanger 2 with connect third pipeline 12 one end on the first pipeline between trachea two-way valve 6, the third pipeline 12 other end is connected between trachea two-way valve 6 and air heat exchanger 4, it has compressor 1 to establish ties on third pipeline 12.
The compressor also comprises a four-way valve 9, wherein the first end and the second end of the four-way valve 9 are connected with the two ends of the compressor 1; the third end of the four-way valve 9 is connected between the air pipe two-way valve 6 and the air heat exchanger 4 through a fourth pipeline 13, and the fourth end of the four-way valve 9 is connected between the air pipe two-way valve 6 and the input end of the water heat exchanger 2 through a fifth pipeline 14.
As shown in fig. 2 and 3, this embodiment has more four-way valves than in example 2, and therefore the unit includes a heat pump cooling mode, a heat pump heating mode, a reverse cycle defrosting mode, and a fluorine pump defrosting mode.
Wherein, under the three modes of heat pump refrigeration, heat pump heating and reverse cycle defrosting, the fluorine pump, the liquid pipe two-way valve and the air pipe two-way valve are all kept closed, and the operation of the fluorine pump, the liquid pipe two-way valve and the air pipe two-way valve is the same as that of a conventional air source heat pump.
In the fluorine pump defrosting mode, the compressor is closed, the fan is closed, the liquid pipe two-way valve and the air pipe two-way valve are opened, and at the moment, the air heat exchanger and the water heat exchanger are directly communicated through the fluorine pump and form the circulation of the fluorine pump. The defrosting principle is the same as that of the embodiment 1, and the unit adopts a defrosting method of 'fluorine pump defrosting is prior', and the process is as follows:
a defrosting method of an air source heat pump unit with a fluorine pump defrosting function comprises the following steps:
1) in a heating state, the liquid pipe two-way valve 5, the gas pipe two-way valve 6 and the fluorine pump 7 are all closed, the compressor 1, the expansion valve 3 and the air heat exchanger 4 are started, the four-way valve 9 connects an exhaust port of the compressor 1 with the water heat exchanger 2, and connects an air suction port of the compressor 1 with the air heat exchanger 4; when the defrosting state is reached, the compressor 1 is closed, the air heat exchanger 4 is closed, and t is kept1Time;
2) opening an air pipe two-way valve 6 and a liquid pipe two-way valve 5, opening an air heat exchanger 4, a water heat exchanger 2 and a fluorine pump 7, closing an expansion valve 3, starting a fluorine pump defrosting mode, and starting to calculate defrosting duration;
3) when the defrosting time reaches t2Detecting the temperature T of the refrigerant at the inlet of the air heat exchanger 41And outlet refrigerant temperature T2And the water temperature T at the inlet of the water heat exchanger 23And the outlet water temperature T4When the defrosting time is accumulated to tmIf any one of the following conditions is met, the step 4) is carried out, otherwise, the step 5) is carried out
T2>Tsf；
T1-T2<Tdf；
T4-T3<Tdw；
Wherein, t1，t2，tm，Tsf，Tdf，TdwAll the parameters are system variable parameters and can be adjusted at will according to actual conditions.
4) After defrosting is finished, the liquid pipe two-way valve 5, the gas pipe two-way valve 6 and the fluorine pump 7 are closed;
5) the fluorine pump is closed, and liquid pipe two-way valve 5 and gas pipe two-way valve 6 are closed, and the system switches to traditional reverse cycle defrosting mode, and expansion valve 3 adjusts to the defrosting aperture, and compressor 1 opens, and cross valve 9 switches to compressor 1 gas vent and wind heat exchanger 4 and connects, and compressor 1 induction port and water heat exchanger 2 are connected to begin the timing, if when reaching following arbitrary condition, the defrosting finishes:
duration of defrosting>tm1；
T2>Tsf1；
Wherein, tm1，Tsf1All the parameters are system variable parameters and can be adjusted at will according to actual conditions.
Compared with the embodiment 1, the embodiment 2 has the disadvantages that the unit needs to be provided with a four-way valve, the system and the control are slightly complex, the functions are more various, and the reverse cycle defrosting mode is provided and is not limited by the environment and the water temperature. The unit adopts the principle of 'fluorine pump defrosting is prior', namely a fluorine pump defrosting mode is preferentially adopted to reduce defrosting energy consumption, if the fluorine pump mode is used for defrosting completely, the reverse cycle defrosting mode is not operated, and if the defrosting capacity of the fluorine pump is insufficient or the defrosting speed is too low due to factors such as low hot water temperature or low air temperature and the like, and the normal operation of the system is influenced, the reverse cycle defrosting mode is operated to ensure quick and thorough defrosting.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the scope of the claims of the present invention.
Claims (2)
1. The air source heat pump unit with the fluorine pump defrosting function is characterized by comprising a water heat exchanger (2) and a first pipeline (10), wherein the water heat exchanger (2) is sequentially connected with a liquid pipe two-way valve (5), a fluorine pump (7), a liquid storage device (8), an air heat exchanger (4) and an air pipe two-way valve (6) through the first pipeline (10); the output of water heat exchanger (2) with connect second pipeline (11) one end on the first pipeline between liquid pipe two-way valve (5), second pipeline (11) other end is connected between fluorine pump (7) and reservoir (8), it has expansion valve (3) to establish ties on second pipeline (11), the input of water heat exchanger (2) with connect third pipeline (12) one end on the first pipeline between trachea two-way valve (6), third pipeline (12) other end is connected between trachea two-way valve (6) and air heat exchanger (4), it has compressor (1) to establish ties on third pipeline (12).
2. The air source heat pump unit with the fluorine pump defrosting function according to claim 1, further comprising a four-way valve (9), wherein the first end and the second end of the four-way valve (9) are connected with two ends of the compressor (1); and a third end of the four-way valve (9) is connected between the air pipe two-way valve (6) and the air heat exchanger (4) through a fourth pipeline (13), and a fourth end of the four-way valve (9) is connected between the air pipe two-way valve (6) and the input end of the water heat exchanger (2) through a fifth pipeline (14).
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| CN202022746607.8U CN214199278U (en) | 2020-11-24 | 2020-11-24 | Air source heat pump unit with fluorine pump defrosting function |
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| CN202022746607.8U CN214199278U (en) | 2020-11-24 | 2020-11-24 | Air source heat pump unit with fluorine pump defrosting function |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112460848A (en) * | 2020-11-24 | 2021-03-09 | 无锡同方人工环境有限公司 | Air source heat pump unit with heat pipe defrosting function and defrosting method thereof |
| CN112460847A (en) * | 2020-11-24 | 2021-03-09 | 无锡同方人工环境有限公司 | Air source heat pump unit with fluorine pump defrosting function and defrosting method thereof |
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2020
- 2020-11-24 CN CN202022746607.8U patent/CN214199278U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112460848A (en) * | 2020-11-24 | 2021-03-09 | 无锡同方人工环境有限公司 | Air source heat pump unit with heat pipe defrosting function and defrosting method thereof |
| CN112460847A (en) * | 2020-11-24 | 2021-03-09 | 无锡同方人工环境有限公司 | Air source heat pump unit with fluorine pump defrosting function and defrosting method thereof |
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