JPS6219631A - Ventilator of heat exchange type - Google Patents

Abstract

PURPOSE:To thaw ice with little energy and maintain the ventilation function by stopping the fan for air exhaust and operating a damper that communicates the outdoor side supply air channel with the indoor side exhaust air channel and energizing a heating element provided in the outdoor side supply air channel. CONSTITUTION:Normally a damper 9 separates the outdoor side supply air channel 2A and the indoor side exhaust air channel 2B. The ventilator is operated in a low outdoor temperature (under -5 deg.). When ice is formed on the heat exchanger 3, the blower 7 for exhaust air is stopped by a control device 11, and a drive machine 10 is operated to communicate the outdoor side supply air channel 2A and indoor side exhaust air channel 2B, and at the same time a heating element 8 is energized. With this arrangement the indoor air is led into the outdoor side supply air channel 2A, and furthermore it is heated by the heating element 8, so that the ice formed on the exhaust air side channel of the heat exchanger 3 is thawed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a ventilation system that performs air supply and exhaust through a heat exchanger.

[Conventional technology]

Figures 7 to 10 are diagrams showing a conventional heat exchange type ventilation system similar to the one shown in, for example, Japanese Utility Model Publication No. 54-42125, in which Figure 7 is a longitudinal sectional view, and Figure 8 is a FIG. 9 is an enlarged perspective view of the end face of the exchanger, and FIG. 9 is a configuration diagram.

FIG. 10 is an explanatory diagram of freezing.

In the figure, (1) is the main body of the ventilation system, and (2) is the outer box of the main body (1).

(2a) is an outside air inlet provided on the side of the outer box (2).

(2b) is the same air outlet t (2C) is the indoor air suction port 9 (2d) is the same air outlet, (3) is the heat exchanger housed in the outer box (2), and is made of many corrugated plates. (3
a) and a large number of flat plates (3b) having moisture permeability and heat conductivity are alternately laminated, and the corrugated plates (3a) are formed into a prismatic shape by alternately interposing the corrugated plates (3a) with their waveform forming direction changed by 90 degrees. It is placed sideways in the center of the outer box (2) and the 45
It is installed at an angle. (4) is an air filter provided on the inflow side of the supply air of the heat exchanger (3), (5) is an air filter also provided on the inflow side of exhaust air, and (6)
) is the supply air blower installed on the outflow side of the supply air of the heat exchanger (3), (7) is the exhaust blower installed on the outflow side of the exhaust air. It is a flow.

A conventional heat exchange type ventilation system is constructed as described above, and outside air is sucked in through the suction port (2a) by the rotation of the air supply blower (6), as shown in the airflow figure, and passed through the air filter (4).
) and the heat exchanger (3), and is blown into the room from the outlet (2b). In addition, as shown by airflow B, the indoor air is sucked in from the suction port (2C) by the rotation of the exhaust blower (7), and is passed through the air filter (5) and heat exchanger (3).
and is blown out from the air outlet (2d). In this way, heat exchange takes place between the supply air and the exhaust air.

[Problem that the invention seeks to solve]

In the conventional heat exchange type ventilation device as described above, when this ventilation device is used in a cold region, the supply air flow is generally a low temperature air flow, and the exhaust flow B is a high temperature air flow. When the air supply temperature is low (-5℃ or less).

Exhaust flow B is a part (3A) near the inlet of the heat exchanger (3)
in.

Condensation, frost, or ice formation occurs due to the cooling caused by the supply air flow. Therefore, the heat exchanger (3) becomes clogged and the exhaust stream B no longer flows near it. As a result, two parts (3
Since there is no heat exchange in the vicinity of A), the area adjacent to it (6B) will be cooled the most due to the air flow, and ice will form. Therefore, if you manage to drive in this condition.

This time, a portion adjacent to portion (3B) begins to freeze, and finally the entire surface freezes, and exhaust air and heat exchange are no longer performed.

In order to prevent such icing and the resulting functional deterioration, if the heat exchanger (3) becomes icy, a temperature detector and timer are used to intermittently turn on the supply air blower (6).
) was stopped and only the exhaust blower (7) was operated for 5K to melt the ice that had formed.

However, in this case, the following problem occurs.

(7) If only exhaust operation is used, the balance of indoor air will be disrupted,
Because air is sucked in from somewhere else in the room, cold air intrudes. (a) Due to the above, the indoor pressure becomes negative, causing abnormalities in exhaust-type combustion appliances (pot-type kerosene stoves, gas furnaces, etc.) There is a risk of combustion.

(V) If the part (3A) in Figure 4 is clogged with ice, indoor air cannot pass through it, so no heat is applied and the ice does not melt sufficiently.

In addition, as another means, a heating element is provided on the low temperature air (outside air) side to preheat the low temperature air to a temperature (0° C. or lower) at which ice does not form on the heat exchanger (3). However, this requires a lot of energy. For example, indoor temperature 20'C, outside temperature -15'C, ventilation air volume 500
m'/hour, to raise the temperature of air at -15'C to 0°C, assuming the weight of the air is 1.2-/-, 15
X0.24X500X1.2: Z1BGKcal/hour of heat is required, and it takes about 2.5
KW 7 o'clock power is required. this is.

When the temperature exchange efficiency of this device is set to 70%, the amount of heat exchanged with the air heated to 0° C. is 2.016 Kcal, which is a larger value than 7 o'clock, and the energy saving efficiency becomes worse.

In this way, a lot of energy is required to prevent the heat exchanger (3) from being degraded or damaged due to freezing. Also,
The heat exchanger (
When melting the ice mentioned in 3), it is difficult to completely melt it, and the room becomes negative pressure during defrosting operation, which may cause cold air to enter and abnormal heating of indoor heating equipment. There is a problem with this.

This invention was made in order to solve the above problems. Even under low temperature conditions where the heat exchanger freezes, the heat exchanger can melt the ice with a small amount of energy and do not reduce the ventilation function. The purpose is to provide a type of ventilation device.

Another object of the present invention is to provide a heat exchange type ventilation device that can automatically perform an accurate defrosting operation in addition to the above object.

[Means for solving problems]

The heat exchange type ventilation device according to the present invention stops the exhaust blower, operates the damper that communicates the outdoor air supply air passage with the indoor air exhaust air passage, and operates the heater provided in the outdoor air supply air passage. It is designed to be energized.

Further, a heat exchange type ventilation device according to another invention of the present invention includes:
In the above, a temperature detector is provided to detect the outside air temperature, and when this detects a predetermined low temperature, the exhaust blower is stopped, the damper is activated, and the heater is energized at regular intervals. It is.

[Effect]

In this invention, exhaust is stopped by stopping the exhaust blower, indoor air is introduced into the supply air path by operating the damper, and is heated by the heating element and supplied to the heat exchanger.

Further, in another invention of the present invention, when the heat exchanger is in a freezing condition, the heating element is energized at regular intervals,
And this is done automatically.

〔Example〕

Figures 1 to 4 are diagrams showing one embodiment of the present invention.
The figure is a configuration diagram, Figure 2 is an operation explanatory diagram, and Figures 3 and 4 are characteristic curve diagrams.
2d) I +31. (3A)t (3B)? +
61. +71. A and B are similar to the conventional device described above.

In the figure, (c) is the outdoor air supply air path formed between the intake port (2a) and the inflow side of the heat exchanger (3), and (2B) is the connection between the intake port (2C) and the heat exchanger (3). (8) is the heating element provided in the outdoor air supply air passage (2A), (9) is the outdoor air supply air passage (2A) and the indoor exhaust air passage formed between the inflow side of the The drive machine al installed on the partition wall between the air passages (2B)
αυ is a damper that connects the air passages (2A) and (2B) and closes the suction port (2a) when rotated by the air supply and exhaust blower (61, +71. This is a control device (consisting of 3 inches, etc.) that controls the drive machine α0.

In the heat exchange type ventilation system configured as described above, the damper (9) normally isolates the outdoor air supply air path (2A) and the indoor air exhaust air path (2B) as shown in Figure 1. Therefore, the air supply and exhaust operation is the same as that of the conventional device.

Next, when the heat exchanger (3) is operated at a low outside temperature (-5"C or less) and ice forms on the heat exchanger (3), the control device +
1 to stop the exhaust blower (7) and operate the drive unit 01 to open the outdoor air supply air path (2A) as shown in FIG.
) and the indoor exhaust air passage (2B).

The heating element (8) is energized. Now the outdoor air supply air path (
Indoor air is introduced into 2A) and further heated by the heating element (8), so that air is generated in the exhaust side flow path of the heat exchanger (3).
Any ice that has formed will be melted.

FIG. 3 shows that in the apparatus of the above embodiment, the outside air temperature is -15
A curve (13) showing the relationship between the indoor temperature and the time until the onset of freezing in the case of ℃, and a curve I showing the relationship between the time until the air volume decreases by 30% are shown. The relationship between the time required to completely melt the ice and the temperature of the air supplied to the air supply side of the heat exchanger (3) is shown.

As is clear from Figures 3 and 4, the indoor temperature does not have a large effect on the onset of freezing or the time it takes for the wind to drop by 3C%, but it is used to melt the ice in the heat exchanger 13). There is a large difference in melting time between cases. Therefore, if the temperature of the air supplied to the heat exchanger (3) is raised to 20° C. or higher using the heating element (8), ice can be melted in a short time.

- As an example, considering a device with a room temperature of 10°C, a processing air volume of 500 m'/hour, and a heat exchange efficiency of TO%, the 2ML volume is 30
Assuming that thawing operation is started from a % drop.

It takes about 12 minutes to thaw, and during this time the exhaust fan (7) is stopped and circulation operation is started, making ventilation impossible.

When a 2KW heating element (9) is installed and energized, the room air at 10°C is heated to 22°C and the heat exchanger (3) is heated.
), it can be thawed in less than 4 minutes. In this case, if the power is turned on for 4 minutes once every hour and 30 minutes, the power consumption will be 9 KW/hour, making it possible to operate with much less power than the conventional preheating type. .

Also, during thawing operation, stop the exhaust blower (7).

At the same time as switching the damper (9) and energizing the heating element (8).

By reducing the amount of air in the supply air flow path using an air volume adjustment device (not shown), the thawing time will be shortened and the ventilation stop time can be shortened if the capacity of the heating element (8) is the same as the conventional device. becomes. The amount of air blown at this time may be controlled by changing the capacity of the blower motor or by changing the area of the air duct.

Although the damper (9) is rotated by a driving machine (1G), it can also be rotated by two manual drives.

FIGS. 5 and 6 are configuration diagrams showing other embodiments of the present invention.

Figure 5 shows a temperature detector α2 installed at the outside air intake port (2a) to detect the temperature (preset) at which the heat exchanger (3) freezes.
is provided, and when this outputs an output, the control device aυ is operated and the above-mentioned defrosting operation is performed intermittently at predetermined time intervals. This prevents performance deterioration due to freezing and allows operation without impairing the ventilation effect, even under low-temperature conditions.

In FIG. 6, a temperature sensor a2 is provided in the outdoor air supply air path (2A) to detect the indoor temperature when the defrosting operation is started.

When the indoor temperature is sufficiently high (for example, 20° C. or higher) to allow defrosting in a short time, the heating element (8) is not energized. Due to this.

When the indoor temperature is high, power is saved, resulting in further energy savings.

In each of the above embodiments, the heat exchanger (3) was described as using a cross-flow heat exchanger, but it is equally applicable to a 9-turn type, counter-flow type, etc.

Furthermore, although the embodiments have mainly been described for residential use (indoor high temperature, outdoor low temperature), the present invention can also be applied to devices used in low temperature locations such as freezers.

〔Effect of the invention〕

As explained above, in this invention, the exhaust blower is stopped, the damper allows communication between the outdoor air supply air passage and the indoor exhaust air air passage, and the heater provided in the outdoor air supply air passage is energized. So.

Even under low-temperature conditions where the heat exchanger may freeze.

It has the effect of melting ice with less energy and preventing deterioration of ventilation function.

Further, in another aspect of the present invention, the outside air temperature is detected by a temperature detector, and when it detects a predetermined low temperature, the exhaust blower is stopped, the damper is activated, and the heating element is energized at regular intervals. Moreover, since this is done automatically, the power consumption by the heating element or the capacity of the heating element can be reduced.

[Brief explanation of drawings]

Figures 1 to 4 are diagrams showing an embodiment of the heat exchanger wedge type ventilation device according to the present invention, in which Figure 1 is a configuration diagram, Figure 2 is an explanatory diagram of the operation of Figure 1, and Figure 3 is icing characteristics. 4 is a melting characteristic curve diagram, FIGS. 5 and 6 are block diagrams showing other embodiments of the present invention, and FIGS. 7 to 10 are diagrams showing conventional heat conversion type ventilation equipment. in. FIG. 7 is a longitudinal sectional view, FIG. 8 is an enlarged perspective view of the end face of the heat exchanger shown in FIG. 7, FIG. 9 is a configuration diagram, and FIG. 10 is an explanatory diagram of ice formation. In the figure, (mu) is the outdoor air supply air path t (2B) is the indoor exhaust air path, (3) is the heat exchanger, (6) is the air supply blower,
(7) is the exhaust blower, (8) is the heater, (9) is the damper, αυ is the control device, α2 is the temperature detector, and the two people are the supply air flow.
B is the exhaust flow. Note that the same reference numerals in Figure 9 indicate the same or equivalent parts.

Claims (2)

[Claims] (1) A heat exchanger that mutually exchanges heat between two air streams, an air supply blower that supplies outside air sucked into the outdoor air supply duct into the room via the heat exchanger, and an indoor exhaust air duct. an exhaust blower that exhausts the indoor air sucked in to the outdoors via the heat exchanger; a damper that normally closes the outdoor air supply air passage and the indoor exhaust air passage; and connects both air passages when necessary; and the room A heat exchange type ventilation device comprising a heating element provided in an outer air supply air path, and a control device that stops the exhaust blower and energizes the heating element. (2) A heat exchanger that mutually exchanges heat between two air streams, an air supply blower that supplies outside air sucked into the outdoor air supply duct into the room via the heat exchanger, and an indoor exhaust air duct. An exhaust blower that exhausts the indoor air sucked in to the outdoors through the heat exchanger, which always closes the outdoor supply air passage and the indoor exhaust air passage, and communicates the two air passages when an operation command is given. a damper, a heating element provided in the outdoor air supply air path, a temperature detector that detects the temperature of the outside air and operates when it detects a predetermined low temperature, and when this temperature detector operates, stops the exhaust blower. A heat exchange type ventilation device comprising a control device that gives the above-mentioned operation command to the damper and energizes the above-mentioned heating element at regular intervals.