KR100667230B1 - Energy recovery ventilation with defrost damper and method for controlling the same - Google Patents

Abstract

A heat recovery apparatus with a defrost damper and a method of controlling the same are provided to perform a defrosting process of removing frost generated due to freezing of condensate. A heat recovery apparatus with a defrost damper includes a first temperature sensor(300), a second temperature sensor(310), a controller, and a defrost bypass damper(241). The first temperature sensor detects a temperature of the outdoor air sucked through a suction port. The second temperature sensor detects a temperature of the outdoor air heat exchanged in the heat exchange part. The controller outputs a control signal for defrosting the heat exchange part according to a temperature difference detected from the first and second temperature sensors. The defrost bypass damper introduces the indoor air sucked into the exhaust duct into the suction duct according to the defrosting operation control signal output from the controller.

Description

Waste recovery and defrost control method with defrost damper {Energy recovery ventilation with defrost damper and Method for controlling the same}

1 is a cross-sectional view showing the configuration of a general waste heat recovery ventilator.

Figure 2 is a cross-sectional view showing a schematic configuration of the waste heat recovery ventilator having a defrost damper according to the present invention.

3 is a block diagram showing the configuration of a waste heat recovery ventilator having a defrost damper of FIG.

4 is an exemplary view showing a defrost process of the waste heat recovery ventilator having a defrost damper of FIG.

5 is a flow chart showing a defrost process of the waste heat recovery ventilator having a defrost damper according to the present invention.

(Explanation of symbols for the main parts of the drawing)

100: cases 110a, 110b: exhaust duct

111: exhaust inlet 112: exhaust port

120a, 120b: Air supply duct 121: Air supply port

122: air supply outlet 130: heat exchange unit

200: air supply fan 210: exhaust fan

221: air supply damper 231: exhaust port damper

241: defrost bypass damper 300: first temperature sensor

310: second temperature sensor 400: control unit

The present invention relates to a waste heat recovery ventilator having a defrost damper, and more particularly, the air volume and heat exchange efficiency of the waste heat recovery ventilator are reduced due to frost generated in the heat exchange part of the waste heat recovery ventilator when the outside air drops below zero. The present invention relates to a waste heat recovery ventilator having a defrost damper and a defrost control method.

In general, the air in an enclosed space increases the content of carbon dioxide and various harmful substances with time by the breathing of the living being, which interferes with the breathing of the living.

Therefore, if many people stay in a confined space such as an office or a vehicle, the indoor polluted air should be replaced with fresh air from time to time.

At this time, a commonly used ventilation device. Most conventional ventilation apparatuses employ a method of forcibly discharging only indoor air to the outside using a single blower.

However, when forcibly discharging only the indoor air by using one blower, the indoor air is discharged to the outside without filtration and the outdoor air is introduced without heat exchange through a door or window gap, thereby heating and cooling the room. The cost of cooling was unnecessarily high.

In addition, the sudden cold air and heat flows from the outside to the inside of the indoor air due to the rapid temperature change, people in the room feels uncomfortable, especially when the indoor air outside the window or door frame closed only to the outside The inflow of fresh air is blocked and oxygen deficiency can occur, as well as the humidity control of the indoor air is not made at all, although there is a problem that does not maintain a comfortable indoor environment despite the ventilation device is provided.

In order to solve this conventional problem, a waste heat recovery ventilator has been proposed in which outdoor air is first heat-exchanged with indoor air discharged to the outside and then supplied to indoors.

1, the waste heat recovery ventilator is provided with an air supply duct 10 into which the outdoor air flows into the inside of the box-shaped duct 1, and intersects with the air supply duct at a predetermined position. The exhaust duct 20 is guided to the outdoor is provided.

A heat exchanger 30 is provided to exchange heat between the outdoor air that is supplied at the point where the air supply duct 10 and the exhaust duct 20 intersect and the indoor air that is exhausted.

At this time, the air supply duct 10 and the exhaust duct 20 are not interfered with each other by the partition wall 3 partitioning the inside of the duct 1 up and down.

An air supply suction opening 11 is formed at one end of the air supply duct 10 and an air supply outlet 13 is formed at the other end of the air supply duct 10. An exhaust suction opening 21 is formed and at the other end, an exhaust discharge opening 23 communicating with the outdoors is formed.

An air supply fan 15 for forcibly sucking outdoor air is provided at the air supply inlet 11 of the air supply duct 10, and an air exhaust fan for forcibly discharging indoor air at the exhaust outlet 23 side of the exhaust duct 20. 25 is provided.

On the other hand, the heat exchanger 30 has a hexahedral shape in which the upper and lower edges are supported by the duct 1 and the left and right edges are supported by the partition wall 3, and a plurality of air supply passages 37 communicating with the air supply duct 10 therein. ) And a plurality of exhaust passages 39 adjacent to the air supply passage 37 and communicating with the exhaust duct 20.

Although not separately shown in the drawings, a heat exchange plate having excellent heat conduction efficiency is provided at the boundary between the air supply passage 37 and the exhaust passage 39.

At this time, the portion shown by the solid line is the air supply passage 37, and the portion shown by the dotted line is the exhaust passage 39. The operation of the waste heat recovery ventilator having such a configuration is as follows.

First, when indoor air is contaminated to some extent, power is supplied to the exhaust fan 25 so that indoor air flows into the exhaust duct 20 through the exhaust inlet 21, and then the exhaust passage 39 of the heat exchanger 30. ) Is discharged to the outside through the exhaust outlet (23).

At the same time, while supplying power to the air supply fan 15, fresh outdoor air flows into the air supply duct 10 through the air supply inlet 11, and then passes through the air supply passage 37 of the heat exchanger 30. 13) is introduced into the room.

At this time, the indoor air and the outdoor air passing through the heat exchanger 30 will exchange heat through the heat exchange plate. Specifically, the heat exchange occurring in the heat exchanger 30 includes sensible heat exchange between the supplied outdoor air and the exhausted indoor air, and high temperature air in the indoor or outdoor air is below the dew point temp. It is made of latent heat exchange by the condensate produced in the state of.

In the case of the heat exchange type ventilation device, the outdoor air supplied when the room is cooled or heated is primarily heat-exchanged with the indoor air and then introduced into the room, thereby preventing a rapid rise or fall of the room temperature.

However, in the conventional waste heat recovery ventilator, when the outdoor temperature drops to below zero (for example, -10 ° C. or lower) in winter, the heat discharge part in which the cold air is introduced while the air discharged from the room is exchanged with the cold air of the outdoor There is a problem in that frost (frost) caused by condensate occurs.

In addition, the frost generated in the heat exchange unit continuously grows to block the flow path flowing into the heat exchange unit, thereby reducing the ventilation amount and heat exchange efficiency of the heat exchange unit.

In order to solve the above problems, the present invention provides a waste heat recovery apparatus and a defrost control method capable of defrosting frost due to freezing of the condensate generated in the heat exchange part of the waste heat recovery ventilator during the heat exchange between sub-zero outdoor air and indoor air. The purpose is to provide it.

In order to achieve the above object, the present invention provides an air intake duct for sucking outdoor air through a supply air supply and an air duct for inhaling indoor air and exhausting it to the outside through an exhaust port. A waste heat recovery ventilator having a heat exchange unit for exchanging outdoor air with the indoor air, comprising: a first temperature sensor detecting a temperature of outdoor air sucked through the air supply; A second temperature sensor detecting a temperature of the outdoor air heat exchanged by the heat exchanger; A controller for outputting a defrosting operation control signal for defrosting the heat exchange part according to the temperature difference detected from the first and second temperature sensors; And a defrosting bypass damper for allowing the indoor air sucked into the exhaust duct to flow into the air supply duct according to the defrosting operation control signal output from the controller.

In addition, the waste heat recovery ventilator according to the invention is installed in the air supply air supply damper for controlling the suction of the outdoor air into the air supply duct; And an exhaust port damper installed at the exhaust port to control exhaust of the indoor air from the exhaust duct to the outside.

The air supply damper and the exhaust port damper may respectively block the air supply and exhaust ports when the defrost bypass damper is opened.

In addition, the present invention is a defrost control method of a waste heat recovery ventilator having a defrost bypass damper including a defrost bypass damper for introducing the indoor air sucked into the exhaust duct into the air supply duct, the drive of the waste heat recovery ventilator Detecting the temperature of the air sucked from the outside through the first temperature sensor while performing a normal operation, the control unit for controlling the temperature of the outdoor air heat exchanged in the heat exchange unit through the second temperature sensor; Calculating, by the controller, a temperature difference detected by the first and second temperature sensors and comparing the temperature difference with a set temperature range for defrosting operation determination; If the temperature difference calculated as a result of the comparison satisfies the set temperature range for determining the defrosting operation, the control unit terminates normal operation and performs defrosting operation so that indoor air sucked into the exhaust duct flows into the air supply duct; And determining, by the controller, whether the defrosting operation is terminated, maintaining the defrosting operation or performing a normal operation.

The defrosting operation may further include: blocking an air supply damper that blocks outdoor air from entering the air supply duct; Blocking an exhaust damper that blocks indoor air from being exhausted from the exhaust duct; Opening a defrost bypass damper for introducing the indoor air sucked into the exhaust duct into the air supply duct; And an exhaust fan for allowing the indoor air to be exhausted from the exhaust duct to the outside, and an air supply fan for supplying outdoor air heat-exchanged from the air supply duct to the room.

The condition for determining whether the defrosting operation is terminated may include determining whether an opening time of the defrosting bypass damper exceeds a reference time for determining defrosting operation termination or whether the temperature difference between the first and second temperature sensors is the defrosting operation. It is characterized by judging according to at least one condition of whether or not to meet the set temperature range.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

Figure 2 is a cross-sectional view showing a schematic configuration of the waste heat recovery ventilator having a defrost damper according to the present invention, Figure 3 is a block diagram showing the configuration of the waste heat recovery ventilator having a defrost damper of Figure 2, Figure 4 2 is an exemplary view showing a defrost process of the waste heat recovery ventilator having a defrost damper of 2.

2 to 4, in the waste heat recovery ventilator, the exhaust ducts 110a and 110b and the air supply ducts 120a and 120b are partitioned in a rectangular case 100, and the exhaust heat ducts 110a and 110b are indoors. Exhaust port damper 231 for blocking air from being discharged to the outside, air supply damper 221 for blocking outdoor air from entering the air supply ducts 120a and 120b, and air supply ducts 120a and 120b. The first temperature sensor 300 and the second temperature sensor 310 for detecting the temperature of the outdoor air, and the defrost bypass damper for introducing the indoor air sucked into the exhaust duct 110b into the air supply duct 120a ( 241, and a control unit 400 for controlling the normal operation and the defrost operation of the waste heat recovery ventilator.

The exhaust ducts 110a and 110b include an exhaust inlet side exhaust duct 110a for sucking air from the room through the exhaust inlet 111 through the partition wall, and the indoor air sucked into the exhaust inlet side exhaust duct 110a. The exhaust port 112 is partitioned into an exhaust port side exhaust duct 110b for exhausting to the outside.

The air supply ducts 120a and 120b include an air supply side air supply duct 120a for sucking air from the outside through the air supply 112 through a partition wall, and the outdoor air sucked into the air supply side air supply duct 120a. It is divided into an air supply outlet side air supply duct 120b for supplying air to the room through the air supply outlet 122.

In addition, the indoor air and the outdoor are communicated from the exhaust inlet side exhaust duct 110a to the exhaust port side exhaust duct 110b and between the air supply side air supply duct 120a and the air supply outlet side air supply duct 120b. The heat exchanger 130 is installed to heat exchange the air.

In addition, the exhaust inlet side exhaust duct 110a and the air supply outlet side air supply duct 120b are partitioned through the first partition wall 101, and the exhaust inlet side exhaust duct 110a and the air supply side air supply duct 120a are The air inlet side air supply duct 120a and the exhaust port side exhaust duct 110b are partitioned through the second partition wall 102, and the air outlet side air exhaust duct 110b and the air supply outlet side are partitioned. The air supply duct 120b is partitioned by the fourth partition wall 104.

In addition, the exhaust port 112 is rotatably installed around the hinge shaft 230 and includes an exhaust port damper 231 that opens and closes the exhaust port 112 so that the air sucked in the room is not exhausted to the outdoors or exhausted to the outdoors. do.

In addition, the air supply 121 is rotatably installed around the hinge shaft 220 to supply air to the outside or to open or close the air supply 121 so that the air is not sucked from the air supply damper 221 It is provided.

In addition, the third partition 103 forms a through hole in the center so as to communicate between the exhaust port side exhaust duct 110b and the air supply side air supply duct 120a, and rotates about the hinge shaft 240. And a defrosting bypass damper 241 for opening and closing the exhaust port side exhaust duct 110b and the air supply side air supply duct 120a.

In addition, the air supply side air supply duct 120a is provided with a first temperature sensor 300 for detecting a temperature of the air sucked from the outside, and the air supply outlet air supply duct 120b is connected to the indoor air in the heat exchange unit 130. A second temperature sensor 310 is installed to detect the temperature of the heat exchanged outdoor air.

The controller 400 outputs a normal operation control signal for allowing the waste heat recovery ventilator to perform normal operation and a defrost operation control signal for performing defrost operation.

That is, when the waste heat recovery ventilator performs normal operation, the control unit 400 controls the air supply fan 200 for sucking outdoor air, the exhaust fan 210 for sucking indoor air, and the air supply damper. 221 and the exhaust port damper 231 maintain an open state, and the defrost bypass damper 241 outputs a control signal to maintain the closed state.

In addition, when the waste heat recovery ventilator performs the defrosting operation, the control unit 400 operates the air supply fan 200 for sucking the outdoor air and the control signal for stopping the exhaust fan 210 for sucking the indoor air. The mechanism damper 221 and the exhaust port damper 231 maintain the closed state, and the defrost bypass damper 241 outputs a control signal to maintain the open state.

In addition, the controller 400 controls the temperature difference detected by the first and second temperature sensors 300 and 310, that is, the temperature of the outdoor air detected by the first temperature sensor 300 and the second temperature sensor 310. The detected heat exchanger 130 calculates a temperature difference between the outdoor air heat exchanged with the indoor air and determines whether the calculated temperature difference falls within a set range for determining the defrosting operation, and outputs a control signal for defrosting operation or normal operation. Outputs a dedicated control signal.

The setting range for determining the defrosting operation is, for example, the outdoor air temperature detected by the first temperature sensor 300 is -10 ° C, and the outdoor air temperature detected by the second temperature sensor 310 is 10 ° C. In the following case, the controller 400 outputs a control signal for defrosting operation.

This is caused by frost (frost) in the air supply inlet 131 of the heat exchanger 130 due to the temperature difference between the outdoor air and the indoor air during the heat exchange of the cold air in the heat exchanger 130 with the indoor hot air. As a result, the heat exchange efficiency of the heat exchanger 130 is reduced, and the temperature detected by the second temperature sensor 310 is also low.

Next, the defrost control method of the waste heat recovery ventilator having a defrost damper according to the present invention will be described with reference to FIGS.

The control unit 400 opens the air supply fan 200 for sucking the outdoor air, the control signal for operating the exhaust fan 210 for sucking the indoor air, the air supply damper 221, and the exhaust port damper 231 are opened. Maintaining the state, the defrost bypass damper 241 outputs a control signal to maintain the closed state to perform the normal operation (S100) while the temperature of the air sucked from the outside through the first temperature sensor 300 The temperature of the outdoor air heat exchanged by the heat exchanger 130 through the second temperature sensor 310 is detected (S110).

The controller 400 calculates a difference between the temperature values of the second temperature sensor 310 from the temperature values of the first temperature sensor 300 detected in step S110, and the calculated temperature difference is a set temperature range for defrosting operation determination. It is determined whether or not to meet (S120).

If the calculated temperature difference does not satisfy the defrost operation determination set temperature range in step S120, the controller 400 outputs a normal operation control signal to allow the waste heat recovery ventilator to operate normally (S170).

When the calculated temperature difference in step S120 satisfies the set temperature range for determining the defrosting operation, the control unit 400 ends normal operation of the waste heat recovery ventilator, and the indoor air sucked into the exhaust side exhaust duct 110b. The defrosting operation is performed to flow into the air supply duct 120a.

That is, the control unit 400 is configured to exhaust the outdoor air from the air supply damper 221 and the air outlet side exhaust duct 110b to block the outdoor air from entering the air supply side air supply duct 120a for the defrosting operation. The control signal for blocking the exhaust port damper 231 for blocking the output is output to the air supply damper 221 and the exhaust port damper 231, respectively (S130).

After performing the step S130, the control unit 400 opens a control signal for opening the defrost bypass damper 241 so that the indoor air sucked into the exhaust side exhaust duct 110b flows into the air supply side air supply duct 120a. Output (S140).

After performing step S140, the controller 400 outputs a control signal to the air supply fan 200 and the exhaust fan 210 to allow the air supply fan 200 to operate and to stop the driving of the exhaust fan 210. (S150).

When the defrosting operation of the waste heat recovery ventilator is performed through steps S130 to S150, the control unit 400 ends the defrosting operation for determining whether frost formed in the air supply inlet 131 of the heat exchange unit 130 has been removed. It is determined whether or not (S160).

The condition for determining the end of the defrosting operation in step S160 is that the controller 400 supplies the temperature of the air supply side air supply duct 120a and the air supply outlet side air supply duct from the first and second temperature sensors 300 and 310, respectively. Detects the temperature of 120b, determines whether the detected difference in temperature satisfies the set temperature range for the defrosting operation determination, and ends the defrosting operation when the temperature difference is not included in the set temperature range for the defrosting operation determination. The defrost operation end control signal is outputted.

In addition, as another embodiment for determining the end of the defrosting operation, the control unit 400 is driven for a predetermined reference time (for example 30 minutes) from the start of the defrosting operation when the defrosting operation is started so that the defrosting operation time is the reference It is also possible to output a defrosting operation end control signal for terminating the defrosting operation when the time is exceeded.

If the defrosting operation is continued in the step S160, the control unit 400 outputs a defrosting operation control signal to repeat the step S150 from the step S130, and the control unit 400 when the defrosting operation is terminated in the step S160. ) Ends the output of the defrosting operation control signal and outputs the normal operation control signal.

That is, the air supply damper 221 which blocks the outdoor air from flowing into the air supply side air supply duct 120a for the defrosting operation, and the air outlet damper that blocks the indoor air from being exhausted from the air outlet side exhaust duct 110b to the outside. The control signal for opening 231 is output to the air supply damper 221 and the exhaust port damper 231, respectively, and the cutoff signal of the defrost bypass damper 241, the air supply fan 200 and the exhaust fan ( Each of the operation signals of 210 is output to allow the waste heat recovery ventilator to operate normally.

Therefore, it is possible to effectively remove the frost formed on the heat exchanger 130 due to the temperature difference between the outdoor air and the indoor air.

As described above, the present invention can prevent frost from occurring in the heat exchange part due to a temperature difference between outdoor air and indoor air during winter, and also can easily remove frost generated in the heat exchange part. have.

In addition, the present invention has the advantage that can be prevented due to the frost generated in the heat exchanger to reduce the air flow rate and the heat exchange efficiency.

Claims (6)

The air supply duct which sucks outdoor air through the air supply air and supplies the air to the room and the exhaust duct which sucks indoor air and exhausts the air to the outside through the exhaust port are partitioned by the partition wall so that the sucked outdoor air and the indoor air are heat exchanged. In the waste heat recovery ventilator provided with a heat exchanger, A first temperature sensor detecting a temperature of outdoor air sucked through the air supply; A second temperature sensor detecting a temperature of the outdoor air heat exchanged by the heat exchanger; A controller for outputting a defrosting operation control signal for defrosting the heat exchange part according to the temperature difference detected from the first and second temperature sensors; And And a defrost damper including a defrost bypass damper for allowing the indoor air sucked into the exhaust duct to flow into the air supply duct according to the defrosting operation control signal output from the controller. The air supply system of claim 1, further comprising: an air supply damper installed in the air supply port and controlling the outdoor air to be sucked into the air supply duct; And A waste heat recovery ventilator having a defrost damper, characterized in that it further comprises an exhaust port damper installed in the exhaust port to control the indoor air is exhausted from the exhaust duct to the outside. 3. The waste heat recovery ventilator using the defrost damper according to claim 2, wherein the air supply damper and the exhaust port damper block the air supply and exhaust ports respectively when the defrost bypass damper is opened. A defrost control method of a waste heat recovery ventilator having a defrost bypass damper including a defrost bypass damper for introducing indoor air sucked into the exhaust duct into an air supply duct. a) the control unit controlling the operation of the waste heat recovery ventilator detects the temperature of the air sucked from the outside through the first temperature sensor and performs the normal operation, Detecting a temperature; b) calculating, by the controller, a temperature difference detected by the first and second temperature sensors and comparing the temperature difference with a set temperature range for defrosting operation determination; c) When the temperature difference calculated as a result of the comparison of step b satisfies the set temperature range for determining the defrosting operation, the controller terminates the normal operation and performs the defrosting operation so that the indoor air sucked into the exhaust duct flows into the air supply duct. Doing; And d) defrosting control method of the waste heat recovery ventilator characterized in that the control unit determines whether the defrosting operation is terminated to maintain the defrosting operation or to perform a normal operation. The defrosting operation according to claim 4, wherein the defrosting operation of step c further comprises: blocking an air supply damper that blocks outdoor air from entering the air supply duct; Blocking an exhaust damper that blocks indoor air from being exhausted from the exhaust duct; Opening a defrost bypass damper for introducing the indoor air sucked into the exhaust duct into the air supply duct; And And an exhaust fan for allowing the indoor air to be exhausted from the exhaust duct to the outside, and a supply fan for supplying outdoor air heat-exchanged from the supply duct to the room. Defrost control method. 5. The method of claim 4, wherein the condition for determining whether the defrosting operation of step d is finished is whether the opening time of the defrosting bypass damper exceeds the reference time for determining the defrosting operation termination or the first and second temperature sensors. Defrost control method of the waste heat recovery ventilator characterized in that it is determined according to at least one of whether or not the temperature difference satisfies the set temperature range for determining the defrosting operation.

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