FI92528B - Ventilation-heating unit - Google Patents

Abstract

The invention relates to a ventilation-heating unit 10, which comprises a heat storage accumulator or accumulators 7, to which heat energy is conducted from an external heat source 11. The unit 10 comprises a blower 3 for outside air, a blower 18 for outlet air and a blower 5 for inlet air, by means of which latter blower inlet air is blown via the unit's heating storage accumulators 7 by way of the inlet air connections 15. The unit 10 has been integrated to form a compact arrangement that contains the above-mentioned blowers 3, 5, 18 and the air ducts between them. The unit 10 contains a heat exchanger 2, which is arranged in the outlet air duct 16, via which exchanger heat energy is transmitted from the outlet air Ap of the unit to the inlet air Ain of the unit. The cold corner 2K of the said heat exchanger 2 is provided with a system for preventing icing, which comprises a duct 20, that is led from the flow duct 15b for heated air AL, by means of which duct 20 air that is heated up in the said unit 10 can be ducted to the cold corner 2K of the heat exchanger 2. <IMAGE>

Description

5,92528

Ventilation heating unit Ventilations-uppvärmningsenhet

The invention relates to a ventilation heating unit, in particular an apartment-specific unit for apartment buildings, comprising a heating coil or coils into which heat energy is conducted from an external heat source, the unit comprising an outdoor air fan, an exhaust air fan and a supply air fan. which ventilation-heating unit is integrated into a compact switchgear unit comprising the above-mentioned fans and the air ducts between them and which ventilation-heating unit comprises a heat exchanger arranged in the exhaust air duct, through which the thermal energy contained in the exhaust air of the unit is transferred to the unit supply air.

With regard to the state of the art closely related to the invention, reference is made to a ventilation heating system marketed by Fläkt Ab under the trademark "TERMOVENT", which comprises separate air heating units and a heat exchanger for heat recovery from the exhaust air, connected to each other by relatively long pipe connections. These long pipe runs cause, among other problems, difficulties in obtaining a satisfactory level of sound insulation for the system.

25. With regard to the state of the art related to the present invention, reference is also made to FI patent 86768 (applicant and inventor Esa Jaaksi).

One previously unresolved problem is the freezing of said heat exchanger in severe frosts in such ventilation heaters equipped with heat recovery (LTO), in particular with a cross-flow plate heat exchanger. The plate heat exchangers of the ventilation LTO device, which are already known, are already frozen at outdoor temperatures of -5 ° C ...- 10 ° C, depending on the exhaust air conditions and the air volume-35 flow ratio. Known defrosting and anti-freezing methods significantly reduce the temperature efficiency of the device, cause sudden changes in supply and exhaust air flows and require. often bypass and shut-off devices.

92528 2

It is a particular object of the invention to provide new solutions to the problems discussed above.

The general object of the present invention is to provide a ventilation-heating unit 5, in particular an apartment-specific unit in apartment buildings, by means of which fresh air can be supplied to the apartment without drafts, while providing heating as required. In addition, it is a general object of the invention to further develop the state of the art and to eliminate the drawbacks which appear therein.

10

In order to achieve the above and later objects, the invention is mainly characterized in that the cold corner of said heat exchanger is provided with an antifreeze system comprising a duct derived from a heated air flow duct, through which heated air can be supplied to the cold corner of the heat exchanger.

The freezing of the ventilation plate heat exchanger belonging to the unit according to the invention can be prevented without significantly degrading the temperature efficiency of the unit even at outdoor temperatures of -20 ° C to -30 ° C depending on the exhaust air conditions and the air volume flow ratio. The supply air flow can be controlled in a controlled manner and no complicated bypass and shut-off devices are required.

; In the following, the invention will be described in detail with reference to some application examples of the invention shown in the figures of the accompanying drawing, to the details of which the invention is in no way narrowly limited.

Figure 1 schematically shows a ventilation heating system of a block of flats composed of ventilation heating units according to the invention.

Figure 2 shows an internal and external connection diagram of a ventilation-heating unit according to the invention.

35 li 92528 3

Figure 3 shows a vertical cross-section of an integrated ventilation heating unit according to the invention.

Figure 1 schematically shows a ventilation-heating system of an apartment building composed of ventilation units 5 (hereinafter unit) according to the invention. The layers K and K2 are different in each apartment has its own unit 10 to which the outdoor air introduced into apartment- specifically in the direction of the arrow Ain, generally relatively short inlet tube unit 10 through 22K tuloilmayhteeseen 22a (Figure 3). The exhaust air is taken out through the exhaust air connections 16, preferably the cooker hood, and led through the apartment-specific duct 16K to the exhaust air connection 16a of the unit 10. Exhaust air is removed from each unit 10 through the channel 24 in the direction of the arrow Aout exhaust air duct 24 through which is connected to the conduit 16e. Recirculated air is taken into unit 10 via 21a in the direction of arrows AK 15 from one or more points in the apartment. Figure 1 further shows zone heating devices 25 connected to the co-operation via the units 10, such as floor heating devices and air exchange devices in the basements K0, comprising an exhaust air connection 26a, an exhaust air duct 26 and a top extractor 27.

20

The ventilation-heating unit 10 according to the invention is integrated in one compact housing (Fig. 3) with vertical walls 10a, a bottom wall 10b and a top wall 10c and a bottom and cover wall, the latter being openable for maintenance. Connected to the upper wall 10c of the unit 10 are connections 15c, 16a, 16e, 21a and 22a of the air ducts entering the unit 10. The height of the unit 10 is denoted by H, the width by L and the depth by S. Said dimensions are typically selected from the ranges: H-1000-1400 mm, L-900-1000 mm and S-300-500 mm.

30 of Figures 1-3 in accordance with the unit 10 provides the outdoor air in the direction of the arrow Ain through the outdoor air filter 1, which supply air is transferred via conduit 22a ristivirtalevylämmönsiirtimelle 2. The heat exchanger 2 to the supply air is recovered from the exhaust air Aout its contained heat energy. Heat exchanger 2, the output side of the channel portion 22b tuloilmavir-35 Ai goes purity as shown in Figure 3 uikoilmapuhaltimen three suction side of the channel portion 22c and further to the pressure downstream of the fan 3 92 528 4 • the increase in the discharge duct part 22d, which is connected to the suction side of the supply air fan 5 to the channel portion 21e.

The recirculating air flow AK is taken to the unit 10 via an inlet connection 21a, from where it passes through a duct 21 delimited by the vertical wall 10a of the housing of the unit 10 to its part 21b. 21 portion of the channel 21c of the circulation air flow moves on to the unit 10 of the housing bottom wall 10b above the chicken vaosan 21c via the inlet air filter 4 through the intermediate wall lOd opening 21d through the supply air fan 5 of the suction channel portion 21e, which must also be 10 outside the inlet air flow Ai. After the pressure increase of the supply air fan 5, the air flow Aink passes through the duct part 15a through the supply air filter 6 to the supply air heating coils 7, where it heats up. The heated supply air flow A1 passes to the duct section 15b and from there through the outlet air sources 15c of the unit 10 to the supply air devices 15, from which heated fresh air is blown into different rooms 15 in the direction of the arrows AL. The supply air fan 5 is used to set the amount of heated supply air A1 required for heating, which is selected according to the size of the apartment and the heating need.

According to Figure 2, a heat source 11, 20, e.g. district heating, is connected to the heating coils 7. As is known per se, the heat transfer system between the heating coils 7 and the heat source 11 comprises a piping 23, a circulating water pump 19 and a heating circulating water differential pressure regulator 19a. In addition, control devices 8 for the supply air heating coils 7 are connected to the piping 23, which receive their control pulses, e.g. from a temperature sensor 8a in the mass of the exhaust air devices 16a.

The cold corner 2K of the cross-flow plate heat exchanger 2 of the unit 10 is exposed to freezing during frost. Cold supply air Ain condenses and freezes the exhaust air water to this corner 2K, where the water freezes because the exhaust air flow Aout is not sufficient to keep the temperature of that corner 2K above zero. In order to eliminate the above-mentioned drawback, an air bypass duct 20 is connected to the heating air duct 15b after the heating coils 7, which is connected by a connection 20a to the duct part 15b and via the control and closing device 20b to the cold corner 2K of the heat exchanger 2.

According to Fig. 2, the control-closing device 20b of the bypass duct 20 is controlled by a temperature sensor 20c arranged in connection with the supply air flow Ain.

li 92528 5 In the event of a risk of freezing, a warm bypass air flow Ac is directed to the cold corner 2K, which ensures that the heat exchanger 2 remains completely unfrozen even in the harshest frosts. Freezing of the heat exchanger 2 can be prevented by a rather small amount of air flow Ac, which does not significantly impair the temperature efficiency of the unit 10, does not cause sudden changes in the supply and exhaust air flows and does not require complex bypass and shut-off damper equipment.

According to Fig. 2, the operation of the unit 10 is controlled by common control and drive devices 13 of the exhaust 18 and outdoor 10 fans, which are controlled by a temperature sensor 13a located in the exhaust air duct part 16c. The supply air fan 5 is controlled by a control and drive device 14.

In the following, the claims are set out, within the scope of the inventive idea defined by them, the various details of the invention may vary and differ from those set forth above by way of example only.

Claims (5)

92528 6 A ventilation-heating unit (10), in particular an apartment-specific unit for apartment buildings, comprising a heating radiator 5 or radiators (7) to which thermal energy is conducted from an external heat source (11), each unit (10) comprising an outdoor air fan (3), an exhaust air fan (18) and a supply air fan (5), the latter of which blows supply air through the heating coils (7) of the unit via supply air connections (15), the ventilation heating unit (10) being integrated with the above-mentioned fans (3,5,18), and a ventilation unit (10) comprising air ducts therebetween, each ventilation heating unit (10) comprising a heat exchanger (2) arranged in the exhaust air duct (16), through which the thermal energy contained therein is transferred from the exhaust air (AP) of the unit to the supply air 15 (Ain); that the cold corner (2K) of said heat exchanger (2) is provided with its anti-freeze system a system comprising a duct (20) derived from the heated air (AL) flow duct (15b), by means of which heated air can be led in said unit (10) to a cold corner (2K) of the heat exchanger (2). 20 A unit according to claim 1, characterized in that said antifreeze system comprises a bypass duct (20) derived from the overpressure flow duct (15b) of the heated supply air (A1). Unit according to claim 2, characterized in that the flow (Ac) of said bypass duct (20) is controlled by means of a control and / or damper device (20b, 20c), which device (20b, 20c) preferably receives its control pulse from a temperature sensor ( 20c). 30 Unit according to any one of claims 1 to 3, characterized in that said heat exchanger is a cross-flow plate heat exchanger (2). A unit according to any one of claims 1 to 4, in the upper part of which, in the vicinity of its second vertical wall (10a), the part (16b) of the exhaust air duct II :: 92528 7 and the recirculating air duct part (21b) and the recirculating air duct part (21c) above the unit ) having a recirculating air filter (4) and having, in connection with the second vertical wall (10a) of the unit (10), from below, the outlet end of the recirculating air duct (21c), a tu-5 air blower (5), a supply air heating coil or coils (7), tu -loilmakanavan pressure side portion (15b), and a heated air supply (AL), a conduit or conduits (15c), characterized in that adjacent to said heating head, ester or reservoirs (7) is a heat exchanger (2) and above Extract air (16a) and a spigot ( 22a) and below the heat exchanger 10 (2) there is an exhaust air fan (18). 92528 8