All about the outdoor unit of the air conditioner. Air conditioner outdoor unit: size, installation, maintenance Schematic diagrams of the air conditioner

Air conditioning has become a habit household appliance. Of the variety of air cooling devices, the most popular are split systems consisting of two units-blocks, one of which is installed outside the room, and the other is inside. The indoor unit of the air conditioner is a complex device that takes warm air out of the room and sent back chilled.

Any air conditioner functions due to the properties of liquids to release thermal energy when liquid is released and absorb heat when it evaporates.

The indoor unit is always placed indoors (usually mounted on a wall or ceiling), and the outdoor unit is taken out of it. Both blocks are interconnected by electrical wiring and copper pipeline through which freon circulates continuously during operation.

Regardless of the design and dimensions, the indoor unit of a split system must have the following components in its design:

• Compressor. Responsible for the compression of the refrigerant and its circulation in a closed circuit.
• Evaporator (heat exchanger). Freon is converted from liquid to gas in this radiator.
• Fan. Forces the air flow going to the evaporator.
• thermostatic valve. Helps reduce refrigerant pressure before the evaporator. As a rule, it is a thin, spiral-curved copper tube.
• A set of filters. Detain dust and larger fractions of debris, inevitably contained in the room air.
• Air distribution system.
• Blinds responsible for the direction of air flow.
• Temperature sensors.
• LED indicators.
• Information table.

Indoor unit design

Note! Since the indoor unit of a split system is often located at an unattainable height, the device always includes a remote control.

Outdoor unit it is simpler, and instead of an evaporator, the device has a capacitor - a unit responsible for the phase transition of freon from a gaseous state to a liquid one.

Implementation of new technological solutions in household equipment often runs counter to practical expediency. Example climate technology most significant in this respect. Yes, in Lately the market is actively filled with which are intended for indoor use. The features of such systems include the complete exclusion of dirty installation operations, which attracts a considerable audience of consumers. But with all the ease of installation and further maintenance, such models are not able to approach the performance characteristics provided by the external air conditioner unit as part of a split system. Another thing is that the owners of outdoor installations have to deal with troublesome tasks, but of a different kind.

What is an outdoor unit?

The composition of the outdoor segment, which is part of the split system complex, includes a condenser, valve decoupling, pipes, filter driers and a fan. Depending on the modification and design, the internal "stuffing" may vary, but the traditional air conditioner kit with a remote unit has just such a set of elements. By the way, the most noticeable differences are observed in the so-called winter systems, which provide for the presence of special controllers for controlling the fan. Modern air conditioners also use multifunctional power switching relays. Such devices are designed for non-standard operation of the compressor in conditions of high or low temperatures. Unlike the internal segment, outdoor unit does not have electronic modules- his work is completely subordinated to the mechanical function.

Block sizes

The outdoor unit is available on the market in various configurations and shapes. And although manufacturers, in order to simplify segmentation, seek to unify model lines, the choice of sizes is still quite wide. If we talk about average parameters, then it has a width of 770 mm, a height of 450 mm and a thickness of 245 mm. At the same time, the radius of the fan varies on average from 200 to 250 mm. Of course, there are also aggregates, the sizes of which deviate from these indicators. So, in the Mitsubishi lineup, an almost square-shaped external air conditioning unit is presented, which has a width of 880 mm and a height of 840 mm. As for the parameters of the internal segment, they are not so impressive. Usually these are long narrow modules of medium size - 700 x 200 x 200 mm.

Choosing a place to install the unit

Usually, when choosing the optimal point for installing air conditioners outside, users are faced with the problems of combining ease of use and protection of the module. For example, the location of the block at height is the best option from the point of view of its safety, but in this case, access to the air conditioner for the purpose of maintenance becomes more difficult. A good solution would be to place the module on the wall near the window opening or loggia. At the same time, other nuances must be taken into account, including the absence of direct sunlight and permission for installation from neighbors, since a noisy unit can cause inconvenience to people living on the same level of the building.

In addition, it produces condensate, which will drip down in drops. Accordingly, you will have to negotiate with neighbors on the lower floors. In case of successful coordination of the installation site of the unit with other residents, you can proceed to direct installation operations. By the way, another condition for installing an outdoor unit is the possibility of laying communications in the wall.

Installation of the external unit of the air conditioner

When installing air conditioners, special installation kits are used, which include pipes with flex, brackets with sets of fixing hardware, drainage communications, etc. The physical installation of the segment is carried out using load-bearing components that are embedded in the walls using anchor elements. At the same stage, brackets are used, the power potential of which is oriented to the mass of a particular module. Also, the installation of the external unit of the air conditioner provides for its communication connection with the internal segment. To do this, a hole of the required diameter is made in the wall, which will allow organizing, in addition to the main wiring, also a gasket vacuum pump and manometric manifold. At the final stage, a direct connection of communications between the two blocks is made.

Features of installing the indoor unit

When installing the evaporative, that is, the internal module of the air conditioning system, it is especially important to observe the correct position of the unit. Usually this unit is mounted directly under the ceiling surface with a slight indentation. Mechanical fixation is also carried out using suitable brackets. True, in this case, the mass of equipment is not so large, which simplifies the workflow. After marking, the master installs the anchor elements and, if necessary, fastens bearing profiles. Next, the indoor unit of the air conditioner is installed with strict observance of the horizontal position. Also, some models of such segments, according to the instructions, should have a slight slope towards the passage of drainage.

Maintenance and care

In normal operation, every six months, the air conditioner should be subjected to after-sales service. Most of the work is carried out with the external unit, which is most prone to contamination. Specialists usually check the condition of the filters, the refrigerant level, operating pressure module traces, etc. The most difficult operation is the replacement of the working fluid. The refrigerant is a chemically unsafe substance, so it is better to trust its refueling experienced craftsmen. But the care of the rest of the components is quite accessible to ordinary users. For example, the answer to the question of how to clean the external unit of an air conditioner is quite simple. First of all, it should be disassembled, after which, using a rag or a vacuum cleaner, rid the internal surfaces of the module of dust and dirt deposits. In the process of such care, external filters and heat exchangers are cleaned, which prolongs the life of the air conditioner.

Outdoor unit in multi-systems

The concept of technical implementation of a split system provides for the possibility of using several indoor modules in one complex, which are serviced by one outdoor unit. Unlike standard configurations, the external module of such a system has engineering differences. For integration into a multi-system, it is equipped with an additional thermostat, which allows you to more effectively control the settings of the fan and compressor. In turn, the indoor unit of the air conditioner acts as a source of information signals that determine the control of the outdoor module. That is, the user, using the remote control, accesses the panel of the indoor unit, and he, in turn, digital channel regulates the system of bypass communications on the freon line.

A question of price

In modern modifications, split-system air conditioners are not cheap, which is largely due to the complexity of the design. Even in the initial segment, the cost of an air conditioner with a remote unit is rarely less than 20 thousand rubles. Of course, you can find options for 15 thousand rubles. from little-known brands, but their quality is questionable by both specialists and users themselves, who often complain about problems.

Decent quality models are offered by Fujitsu, Daikin, Mitsubishi, etc. average cost air conditioner from the range of these companies varies in the range of 30-40 thousand rubles. At the same time, the most technologically advanced and productive kits can be estimated at 70-80 thousand rubles.

Conclusion

The use of air conditioners with a design that involves the installation of a remote unit causes many problems during installation and further maintenance. And this is without taking into account the difficulties in transporting equipment. These factors allow us to speak of such units as obsolete. Especially against the backdrop of the spread of mobile devices with a modest size. Nevertheless, the external unit of the air conditioner remains relevant in the market. This is explained by its high performance, functionality and safety during operation, since the main work units are located outside the living quarters. And if for domestic use you can find a low-power replacement for a split system in the form of a monoblock, then in the context of maintenance office space, public buildings and institutions multifunctional complexes are still unmatched.

Often, during repairs, many people think about installing a split system and plan the design of rooms to fit the size of the air conditioner. indoor unit this device it is necessary to place it in such a way that it is not only correctly located, but also looks most harmoniously in the intended interior.

The purchase and choice of the air conditioner itself is often planned closer to the end of the repair, and you need to supply the “power” now. So this article is written for such cases. In it, we will consider in detail what distances must be taken into account for subsequent installation, and identify the most universal sizes indoor units (wall-mounted household appliances).

First, we want to warn you right away that there are “non-standard” models of air conditioners that can have unique dimensions and characteristics. And therefore this article should not be taken as 100% universal.

Air conditioner size. Split indoor unit

Most often living rooms have a small area (up to 25 sq. m.) Air conditioners up to 2.7 kW are suitable for such premises (do not confuse with power consumption) - they are usually called "sevens" or "nines". As a rule, "sevens" and "nines" (of the same model) have the same dimensions, as well as the same diameter of the tubes. Therefore, further we will take into account the same dimensions and characteristics of the considered standard sizes.

Overall dimensions of the indoor unit, which we are primarily interested in

• block length. The most standard length of indoor units is 700-800 mm. Slightly less common up to 900 mm. By personal experience it is best to take into account average length 770 mm.
• block height. Most often, these dimensions lie in the range of 250-290 mm. For planning, we will take into account 270 mm.

We are not very interested in depth (170-240 mm). Thus, we have identified the average size of the internal block 770 x 270 mm.

Distances from walls and ceiling

1. Air conditioners "on / off". The cable is brought out in such a way that it is subsequently located under the indoor unit ( to the left by 300 mm. and lower by 100 mm. from the center of the block).
2. Most

MEL group of companies - wholesale supplier of air conditioning systemsMitsubishiHeavyIndustries.

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Before considering such a seemingly simple topic as the maximum length of air conditioner pipelines (open the manufacturer's catalog and see what the maximum length is), I want to ask one question: what is an ENGINEER in our specialty? The one that looks into the directory and gives out what is written there? But this can be done by an ordinary manager, knowledge of hydraulics and thermodynamics is not necessary for this. Probably, an engineer is a specialist who sees a little deeper than the numbers in the catalog. A specialist who can explain where these numbers come from.

I remember there was a dispute with a respected person who, in defense of the catalogs, said the following phrase: “If I have instructions on how to build a BLUE house, then I cannot build a RED house using it, because this would be a violation of the instructions ... "

So here is an ENGINEER, this is probably a person who can build a "house" of any color: understanding what a foundation is, bearing walls, floors and roofing of the building. It does not matter what color the house will have.

Split air conditioning systems have one important characteristic - maximum distance from outdoor unit to indoor unit. Moreover, on real objects, this parameter often becomes decisive when choosing an air conditioner. The greater the cooling capacity of the air conditioner, the great length air conditioning routes are allowed by the manufacturer (table 1 on the example of Mitsubishi Heavy Industries).

Table 1.

For models of 2 kW of cold, the maximum length of the route for the air conditioner is, as a rule, 15 meters, and for semi-industrial models of 7 kW and above - up to 50 meters. For some models, the length of the pipelines can reach 100 meters.

But one thing is often forgotten important detail– the performance of the air conditioner in the catalogs is indicated with a standard length of pipelines of 7.5 meters, and with a maximum length, the performance of the air conditioner will be less. How much less - look at these tables:

Table 2.

Equivalent length - the length of a straight pipeline, the pressure loss in which is the same as the real one (with local resistances).

In principle, the power loss is not large - for the 50th model with a length of 30 meters (equivalent length), the losses during cold operation are only 3.4% of the power. On the other hand, for the 140th model, the losses for 50 meters of length are already 17%.

Now we need to turn our attention to theory.

On fig. 1 shows a classic freon cycle in an air conditioner circuit. And please note that this is a cycle for ANY systems based on R410A freon, the cycle does not depend on the performance of the air conditioner or brand. Let's start from point D, with the parameters at which (temperature 75C, pressure 27.2 bar) freon enters the condenser of the outdoor unit. Freon in this moment- this is a superheated gas, which first cools to the saturation temperature (about 45 ° C), then begins to condense and at point A, completely passes from gas to liquid. Then the liquid is supercooled to point A' (temperature 40C). It is considered that optimal value hypothermia 5C. After the heat exchanger of the outdoor unit, the refrigerant enters the throttling device (TRV or capillary) and its parameters change to point B (temperature 5C, pressure 9.3 bar). Moreover, it is important that after throttling, it is precisely the mixture of liquid and gas that enters the liquid pipeline. The greater the amount of freon subcooling in the condenser, the greater the proportion of liquid freon enters the indoor unit, the higher the efficiency of the air conditioner.

B-C - the process of freon boiling in the indoor unit with a constant temperature of about 5C, C-C '- freon overheating up to + 10C.

C ' - L - the process of freon suction into the compressor and pressure loss at the same time. A similar process is D' - M.

L - M - the process of compressing gaseous freon in a compressor with an increase in pressure and temperature.

Rice. 1. Freon cycle refrigeration machine on the I-lgP diagram

Freon R410A parameters at the key points of the refrigeration cycle

The pressure loss in the system depends on the freon velocity V and the hydraulic characteristics of the network:

Liquid pipeline - 0.3-1.2 m / s

Gas pipeline - 6-12 m/s

What will happen to the air conditioner with an increase in the hydraulic characteristics of the network (due to an increased length or a large number of local resistance)? Increased pressure losses in the gas pipeline will lead to a pressure drop at the compressor inlet. The compressor will capture refrigerant of lower pressure and therefore lower density. The refrigerant consumption will drop. At the outlet, the compressor will produce less pressure and the condensing temperature will drop. A lower condensing temperature will result in a lower evaporation temperature and freezing gas pipeline.

If increased pressure losses occur in the liquid pipeline, then the process is even more interesting: Since we found out that freon is in a saturated state in the liquid pipeline, or rather, even a mixture of liquid and gas bubbles, then any pressure loss will lead to a slight boiling of the refrigerant and an increase in the share of gas. An increase in the share of gas will lead to sharp increase the volume of the gas-vapor mixture and an increase in the speed of movement through the liquid pipeline. The increased speed of movement will again cause increased pressure losses and the process will be "avalanche". Here is a conditional graph of specific pressure losses depending on the speed of freon in the pipeline:

Rice. 2. Freon pressure loss along the length of pipelines.

It can also be viewed as a graph of pressure loss along the length. If, for example, the pressure loss with a pipeline length of 15 meters is 400 Pa, then if the pipeline length is doubled to 30 meters, the losses increase not twice to 800 Pa, but 7 times to 2800 Pa. Therefore, a simple increase in the length of pipelines by a factor of two relative to its standard lengths fatal for the air conditioner.

How to increase the length of the traces more than the standard allowable values?

To do this, two problems need to be solved:

Problem 1 - the problem of increased pressure losses along the length in pipelines.

As we found out, increased pressure losses lead to a sharp decrease in the cold power of the air conditioner, a decrease in freon consumption and overheating of the compressor. Which in turn will lead to jamming or burning of the motor windings. To prevent this from happening, we must reduce the specific pressure loss by reducing the speed of movement in pipelines. Those. simply increase the diameters of the pipelines. Reducing the speed of freon by half reduces the pressure loss by 4 times (formula 1) and, accordingly, by the same amount allows you to increase the length of the pipelines.

To test this on real equipment, let's look again at Table 2: cold power losses for the 71st and 140th models at a length of 50 meters.

71st model correction factor 0.94. Losses 6%

140th model correction factor 0.829. Losses 17.1%

This means that the pressure loss decreased 17.1/6=2.85 times

The 140th model is exactly twice as powerful as the 71st, and the pipelines there are the same (3/8 and 5/8). Therefore, the speed of freon movement is exactly two times less. The pressure loss, which is quadratic with speed, should be around 36%. In fact, less, because the reference point is not from 0 meters, but from 7.5 meters.

That is, when the freon speed is halved, the pressure loss also decreases at least twice (in practice, more than twice).

Now let's look again at table 1:

The 6.35mm liquid line diameter works on both the 2.0kW system and the 7.1kW system. On the 7 kW model, the length of the pipes can reach 30 meters, which means that there are no critical pressure losses with such a length. The available pressure of the compressor, as we have already found out, does not depend on the power of the air conditioner. Therefore, the same liquid pipelines for models from 2 to 7 kW are explained by the absence of pipes of a smaller diameter. For models from 2 to 5 kW, the liquid pipeline is taken “with a margin”.

But the diameter of the gas pipeline is chosen closer to real values, so its cross section varies from 9.52 mm to 15.88 mm.

Given all of the above, we can make the following table:

Table 3. Magnification allowable length pipelines when changing their diameter.

Power loss at the specified maximum length will be from 10% to 15%. As shown in Table 2, MHI power losses are allowed up to 20%.

Problem 2 - oil return to the compressor.

By increasing the diameter of the gas pipeline, we reduce the speed of the refrigerant, which means that the effect of oil separation and stagnation in pipelines and “oil traps” may occur. To prevent this from happening, some MHI outdoor units have special devices - oil separators.

Rice. 3. Scheme freon circuit outdoor units FDC200 (250)VS

Table 5. Power loss of outdoor units 200 and 250 index at different diameters gas pipeline.

But most outdoors do not have oil separators. On the other hand, the problem of oil separation was more typical for R22 freon. Firstly, because the viscosity of mineral oil used with R22 freon is greater than polyester oil for R410A freon. Secondly, the density of R410A is higher, the available pressure is higher, so the pipeline diameters are 1-2 sizes smaller.

In any case, an increase in the diameter of gas pipelines is allowed IN HORIZONTAL AREAS. Those. on the vertical sections pipeline, it is necessary to use a standard (catalog) diameter, and on horizontal ones, you can switch to a diameter of a larger section.

Example:

In a residential complex in the city of Perm, on each floor of the building are allocated special rooms for outdoor units of air conditioners. But the length of the pipelines that arises in this case reaches 40 meters. The maximum length of the route of a household split system of any manufacturer is a maximum of 25 meters. However, if the diameter of the gas pipeline is increased to 1/2, the length of the air conditioner pipeline can reach 40 meters. Household model SRK35ZJ-S installed. The area near the outdoor unit is performed as standard (1/4, 3/8), then a transition is made approximately at a distance of 1 meter gas pipe to the diameter of ½ on the solder, and then near the indoor unit, the reverse transition to 3/8. Liquid pipe unchanged.

More than 10 air conditioners have already been installed according to this scheme. The first one was over 2 years ago. All air conditioners are working fine.

Conclusions.

1. Increase maximum length routes of air conditioners are possible with an increase in the diameter of pipelines. Recommendations for the Mitsubishi Heavy Industries brand are shown in Table 3.
2. An increase in the diameter of the gas pipeline is possible only in horizontal sections.

At the same time, it is necessary to carry out additional charging of refrigerant for an increased length of the liquid pipeline according to table 4.

During the operation of a household split system, you can feel bad smell rot along with air currents from the device. It indicates the need for preventive cleaning of the unit. In addition to repulsive amber, clogging of nodes can cause rapid wear of the power unit, increased power consumption and the occurrence of allergic reactions in humans.

This procedure can be entrusted to an employee service center. But if you have been using a split system for a long time, you can handle the work yourself, saving money. It is only necessary to familiarize yourself with the procedure for disassembly and preventive cleaning.

Indoor unit dimensions

Before installing the indoor unit of the air conditioner, you should take an interest in its dimensions. This is especially important when renovating modern technologies quite often provide for the installation of suspended ceiling systems, which can affect the height of the ceiling, as well as the parameters of the described device.

On sale you can find non-standard models that have unique sizes. The length of the block usually varies from 700 to 800 mm. Products up to 900 mm are somewhat less common. Experts recommend taking into account an average length of 770 mm.

As for the height, it is usually equal to 250-290 mm. The average value is 270 mm. Depth is not of great interest to consumers, but it reaches 240 mm. The minimum value is equivalent to 170 mm. From this we can conclude that the average dimensions of the indoor unit of the air conditioner are 770 x 270 mm.

Knowing these parameters allows you to determine at what distance from the ceiling and walls to hang equipment. There are a lot of controversies on this issue. In some instructions, the minimum distance is 50 mm, while in others it goes up to 300 mm. The optimal value is equal to a figure from 60 to 150 mm.

Specialists usually install air conditioning with a distance of 100 mm. Before installing the indoor unit of the air conditioner, it is important to consider whether there will be curtains in the room. The step between them and the split system is usually 150 mm. You can increase this value up to 250 mm. The average distance from the block to the wall is 400 mm.

Classification of indoor units

In order to carry out disassembly, it is necessary to determine the type of indoor unit of the air conditioner, which can be represented:

• wall split system;
• channel air conditioner;
• cassette device.

The most common are wall models, which are more affordable and are sometimes also called household. Their installation can be carried out in a room for any purpose, and the power within 7 kW allows you to cool up to 70 m 2 of area. Such blocks are usually installed in the upper part of the wall, not far from the window, since the design provides for the presence of an outdoor unit, and the nodes must be interconnected.

Wall-mounted air conditioners are not able to supply fresh air to the premises, as this requires a separate ventilation system. If you wondered how to disassemble the indoor unit of the air conditioner, you can read this information below. It is for such a device that the recommendations in the article are given.

Apart from domestic air conditioners, some manufacturers supply semi-industrial devices to the market, the power of which reaches 10 kW. Outwardly, they look like traditional split systems, but in terms of parameters they are semi-industrial equipment.

Ducted air conditioners are installed with suspended ceilings that hide them completely. The distribution of cooled air is provided by heat-insulated air ducts, which are located in the interceiling space. Such structures can cool several rooms at once. The power of the equipment reaches 25 kW, which makes it possible to provide cooling for a cottage or several rooms of an apartment. The main feature of channel systems is the possibility of supplying fresh air in the volume that is guaranteed by the functioning of full ventilation.

Cassette air conditioners require a false ceiling during installation. When compared to duct designs, cassettes distribute cooled air through lower part block. She closes decorative grille and usually has the following dimensions: 600 x 600 and 1200 x 600 mm.

Dismantling and cleaning the air conditioner

To clean the indoor unit of the air conditioner, it is necessary to disassemble it. For this, screwdrivers of various configurations and sizes are prepared. You should take care of the presence of a box for collecting fasteners. Requires electrical and functional diagram device. On some models, they are printed on inside top cover.

To clean the internal elements you will need:

• clean rag;
• detergent;
• a vacuum cleaner.

The first step is to de-energize the air conditioner. This is in accordance with electrical safety regulations. Remove the plug from the socket. The top cover of the block is removed. Bolts are unscrewed, which can be two or three. Usually they are closed with decorative caps. The top cover of the indoor unit is removed. If it is covered with a layer of mold and dirt, it should be washed in the bathroom with detergents and brushes.

When disassembling the indoor unit of the air conditioner, you will need to remove air filters. They are made of plastic and are designed for rough air purification. Sometimes they are fixed on the lid or inside the air conditioner. The filters are washed under an intense stream of water. A brush will help with this.

The airflow guides should also be removed. Blinds are removed from the grooves. To facilitate the process, you need to slightly bend them. These elements direct the flow of cold air into the room and also need enhanced flushing.

Removing the bottom cover

The next step is to remove the bottom cover. Will need to extract drainage tube and power wire. In the process of this, three latches should be pressed and the drain tray together with the outlet hose should be disconnected from the unit.

Removing terminal blocks

The indoor unit of the air conditioner has terminal blocks. They are disconnected during disassembly, and then the electronic control unit and transformer are removed. In order to remove the first one, it is necessary to press side mounts, and then pull the device towards you. Before this, the ground wires are unscrewed.

Removing the fan motor

The fan motor can now be removed. To do this, the bolts are unscrewed, which are strengthened to the chassis. The evaporator is raised and the engine is pulled out along with the rotary fan. The motor must be separated from the fan, but first you have to warm up the bolt head with a soldering iron. This will unlock the thermal lock on the motor pulley. Once the fan blades can be removed, they must be washed. Assembly is carried out in the reverse order.

Cleaning the outdoor unit

Outdoor and indoor units of air conditioners are equally in need of maintenance. The frequency for the first is twice a year, which is true even with intensive use. A vacuum cleaner is required for this, but the device must be powerful enough to extract dust from external filters and heat exchangers.

On your own or with the help of specialists

If the unit is located at an impressive height, then you can unscrew the protective grille and vacuum it, as well as wipe the insides from dust. Otherwise, you can seek help from professionals who will remove the air conditioner using climbing equipment or a tower. Cleaning yourself can be done using compact senders, but the air conditioning system will have to be de-energized and turned on only 30 minutes after the end of the service.

Finally

During the operation of the split system, dust settles on the fan impeller, where a “fur coat” of dirt is formed. This prevents the passage of air flow when blowing the evaporator. The latter freezes over, and the user does not receive normal cold and intense air flow.

Cleaning the fan of the indoor unit of the air conditioner is also required when you see black flakes flying out of the appliance. This suggests that the amount of dirt is so large that it does not hold onto the internal nodes. As a preventive measure, from time to time you can dismantle the fan and wash it. chemicals. But not all models make it easy to extract this part of the system.