An air-source heat pump defrosting water discharge system

Abstract

This utility model provides an air-source heat pump defrosting water drainage system, which includes a water collection tray installed at the bottom of the evaporator; an electric heater installed at the bottom of the water collection tray; a drain nozzle installed on the lower side of the water collection tray; the drain nozzle being connected to a drain pipe; an electric heating tape installed inside the drain pipe; and an insulation pipe wrapped around the outside of the drain pipe. The electric heater is fixed to the bottom of the water collection tray by fixing clips. The electric heater is a resistance type electric heater, and its heating area is in close contact with the bottom of the water collection tray. This utility model features energy-saving and consumption-reducing operation, and a stable and reliable system.

Description

Technical Field

[0001] This utility model specifically relates to an air source heat pump defrosting water discharge system, which falls under the field of heating, ventilation and air conditioning technology. Background Technology

[0002] During winter operation, frost forms on the evaporator of an air source heat pump. During defrosting, the solid frost undergoes a phase change, turning into liquid water that flows from the evaporator surface into the water collection pan. From there, it is drained through the drain hole and discharged to the outside of the unit via a drainage pipe. However, in practical operation, especially in extremely cold climates where temperatures can reach -10°C or even -20°C, the defrosting water often freezes into ice blocks during drainage, affecting the unit's normal heating operation. During the drainage process, ice gradually forms from the drainage pipe → water tap in the water collection pan → water collection pan → bottom of the evaporator, causing ice to form before the defrosting water has completely drained. This results in partial or complete ice blockage of the drainage channels, creating a vicious cycle that hinders the unit's normal operation in extremely cold climates and necessitates frequent manual de-icing. Another situation is that, to keep the water inlet channels clear, some units have electric heating tape installed in the water inlet pan and drainage pipes. In winter heating environments below 5°C, the electric heating tape is powered on 24 hours a day, working whether draining or not, resulting in unnecessary energy waste (defrosting + draining time is generally about 5 minutes, and it is in normal heating state 90% of the time), which is not economical. The traditional practice is to wrap the electric heating tape inside the water inlet pan (which has the defect of uneven heating), but not to wrap the electric heating tape on the drain pipe, resulting in high energy consumption and problems such as ice blockage and poor drainage. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide an air source heat pump defrosting water discharge system that is energy-saving, reduces consumption, and has stable and reliable operation.

[0004] To achieve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: An air-source heat pump defrosting water discharge system includes a water collection tray disposed at the bottom of the evaporator; An electric heater is installed at the bottom of the water collection tray; A drain nozzle is provided on the lower side of the water collection tray; The drain nozzle is connected to the drainage pipe; The drainage tube is equipped with an electric heating tape inside, and the drainage tube is wrapped with an insulation tube on the outside.

[0005] Furthermore, the electric heater is fixed to the bottom of the water collection tray by a fixing clip. The electric heater is a resistance electric heater, and its heating area is in close contact with the bottom of the water collection tray.

[0006] Furthermore, an insulation board is installed below the electric heater, which covers the bottom of the electric heater and the water collection tray to form insulation.

[0007] Furthermore, a temperature control switch is installed inside the water collection tray, and the temperature control switch is connected to the electric heater.

[0008] Furthermore, the temperature control switch is connected to a time delay relay A, which is connected to the heat pump host and receives the defrosting electrical signal from the heat pump host.

[0009] Furthermore, the time-delay relay A is connected to the electric heating tape.

[0010] The beneficial effects of adopting the above technical solution are as follows: During the heating process of air source heat pumps in cold winter climates, defrosting and drainage time accounts for about 10% of the total heating operation time. For the vast majority of this time, the evaporator of the air source heat pump is on the verge of frosting. This invention installs an electric heater at the bottom of the water collection pan and an electric heating tape inside the drainage pipe. This reduces unnecessary heat loss. The on / off operation time of the electric heater and heating tape is controlled by the main unit's defrosting signal and an added delay time, ensuring that heating is maintained only for 5-10 minutes during the defrosting process to keep the drainage channel clear. This precise heating ensures smooth and unobstructed defrost water drainage, eliminating the need for continuous heating. For the vast majority of non-defrosting and drainage time, the electric heater and heating tape do not need to operate. This low-energy, precise heating maintains unobstructed drainage, resulting in greater energy savings. The operation of the electric heater in the water collection pan is controlled by a temperature probe, further saving unnecessary defrosting energy while meeting drainage and antifreeze requirements.

[0011] This invention solves the economic and technical problems of existing air source heat pumps, which require the installation of heating cables in the defrost water collection pan and drainage pipe during winter, resulting in the need to keep them powered on 24 hours a day, leading to energy consumption issues, as well as the unreliability, inaccuracy, and inefficiency of defrost water drainage technology. This invention achieves reliable defrost water drainage while ensuring precise heating and low energy consumption, demonstrating significant economic and technical advantages.

[0012] The electric heating cable of this invention is installed inside the drainage pipe; the electric heater is installed at the bottom of the water collection pan for heating. The water collection pan is heated evenly, which can maintain the defrost water drainage channel from freezing and keep the channel unobstructed. It has higher reliability and less heat dissipation to the outside. It overcomes the problems of high energy consumption and poor drainage caused by winding the electric heating cable inside the water collection pan and not winding the electric heating cable around the drainage pipe.

[0013] The present invention features an electric heater installed at the bottom of the water collection tray and insulated to keep the defrost water collection tray heated and insulated. The heating response time is short and the energy consumption of electric heating is minimal. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the cross-sectional structure of the present invention along the AA direction; Figure 3 This is a bottom view of the water collection tray of this utility model. Figure 4 This is a flowchart illustrating the defrosting and heating process of the present invention. Figure 5 This is a circuit diagram of the control circuit of this utility model; Among them, 1. Evaporator, 2. Water collection tray, 201 Electric heater, 202 Insulation board, 203 Temperature control switch, 204 Drain nozzle, 205 Fixing clip, 3. Drainage pipe, 301 Electric heating tape, 302 Insulation pipe. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings.

[0016] As attached Figure 1-5 As shown, this embodiment provides an air source heat pump defrost water discharge system, which includes a water collection tray 2 installed at the bottom of the evaporator 1; an electric heater 201 is installed at the bottom of the water collection tray 2; there are multiple electric heaters 201, and the electric heaters 201 are fixed to the bottom of the water collection tray 2 by fixing clips 205. The electric heaters 201 are resistance electric heaters, and their heating areas are in close contact with the bottom of the water collection tray 2. A resistance electric heater (in the form of a rod or patch, etc.) is installed at the bottom of the water collection tray 2 of the evaporator, and the heating area is in close contact with the bottom of the water collection tray 2, so that the heating area of ​​the electric heater 2 can conduct heat to the water collection tray instantly and evenly. The water collection tray 2 is in a state much higher than 10°C during the time when the electric heater 2 is powered on. Even in an ultra-low temperature environment of -30°C, the defrost water can be guaranteed not to freeze during the flow of defrost water in the water collection tray.

[0017] A drain nozzle 204 is provided on the lower side of the water collection tray 2; the drain nozzle 204 is connected to the drainage pipe 3; an electric heating tape 301 is provided inside the drainage pipe 3, and an insulation pipe 302 is wrapped around the outside of the drainage pipe 3. A self-regulating electric heating tape is provided from the drain nozzle 204 of the water collection tray 2 and inside the drainage pipe 3 to maintain the temperature inside the flow channel and the environment above 5°C. The electric heating tape is kept energized during the defrosting process of the main unit (and is also controlled by a time delay relay).

[0018] An insulation board 202 is installed below the electric heater 201. The insulation board 202 covers the bottom of the electric heater 201 and the water collection tray 2 to form insulation, ensuring that the heat is locked in as much as possible, so that the heat of the electric heater 201 is not wasted.

[0019] A temperature control switch 203 is installed inside the water collection tray 2. The temperature control switch 203 is connected to the electric heater 201 and a time delay relay A. The time delay relay A is connected to the heat pump main unit and receives the defrost electrical signal from the heat pump main unit. The time delay relay A is also connected to the electric heating tape 301. When the air source heat pump starts the defrost program, it will send an electrical signal to the four-way valve, switching from heating mode to cooling mode. When the unit sends the electrical signal, it simultaneously starts the electric heater and the electric heating tape and extends the time by 3-5 minutes, which can be adjusted according to the actual situation to ensure that the defrost water is drained in time, while preventing the electric heater and electric heating tape from being energized for a long time, thus avoiding unnecessary power waste.

[0020] Wiring and Precision Energy-Saving Control Logic Description The heat pump four-way valve control wire B outputs a power signal, which connects to a time-delay relay A. Relay A outputs two power supplies: one to the electric heater 201, which is continuously powered by the temperature control switch 203 for a set power-on time; the other to the electric heating tape 301. The temperature control switch 203 controls the on / off logic of the electric heater 201: when the surface temperature of the water collection tray 2 reaches a set value (adjustable, e.g., 20℃), the power is cut off; when it falls below the set temperature (e.g., 20℃), the power is turned on. The electric heating tape 301 inside the drainage pipe 3 is always powered on, automatically adjusting the current and power through the self-limiting temperature mechanism of the heating tape. After the time-delay power-on time, both the electric heater and the electric heating tape are de-energized, awaiting the signal from the main unit's defrosting function for the next cycle, and this cycle repeats.

[0021] Since air source heat pumps operate in normal heating mode 90% of the time, defrosting time accounts for approximately 10% of their total operating time. This invention activates the electric heating and electric heating tape during the defrosting period (delayed by a time-delay relay for 3-5 minutes). The main unit sends an electrical signal to the time-delay relay during defrosting, which outputs two channels: one channel connects to the electric heater via a temperature control switch; the other channel connects to the electric heating tape and delays the heating time, maintaining the defrost water channel at a temperature above the non-freezing level to ensure the defrost water channel does not freeze and drains smoothly.

[0022] To further enhance energy efficiency, a temperature control switch 203 is installed on the water collection tray 2. When the temperature of the water collection tray 203 reaches the set temperature, the electric heater 201 is briefly de-energized. The self-regulating heating cable automatically adjusts its current and power to maintain the drainage pipe 3 at a constant, non-icing temperature, ensuring that defrosting water discharge does not cause ice blockage.

[0023] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An air-source heat pump defrosting water discharge system, characterized in that, It includes a water collection tray (2) located at the bottom of the evaporator (1); An electric heater (201) is installed at the bottom of the water collection tray (2); A drain nozzle (204) is provided on the lower side of the water collection tray (2). The drain nozzle (204) is connected to the drain pipe (3); The drainage tube (3) is equipped with an electric heating tape (301) inside, and the drainage tube (3) is wrapped with an insulation tube (302) outside.

2. The air-source heat pump defrosting water discharge system according to claim 1, characterized in that, The electric heater (201) is fixed to the bottom of the water collection tray (2) by a fixing clip (205). The electric heater (201) is a resistance electric heater, and its heating area is in close contact with the bottom of the water collection tray (2).

3. The air-source heat pump defrosting water discharge system according to claim 1, characterized in that, An insulation board (202) is provided below the electric heater (201), and the insulation board (202) covers the bottom of the electric heater (201) and the water collection tray (2) to form insulation.

4. The air-source heat pump defrosting water discharge system according to claim 1, characterized in that, The water collection tray (2) is equipped with a temperature control switch (203), which is connected to the electric heater (201).

5. The air-source heat pump defrosting water discharge system according to claim 4, characterized in that, The temperature control switch (203) is connected to the time delay relay A, which is connected to the heat pump host and receives the defrosting electrical signal from the heat pump host.

6. The air-source heat pump defrosting water discharge system according to claim 5, characterized in that, The time delay relay A is connected to the electric heating tape (301).

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