What is a multi-split system: principle of operation + installation and connection rules

Types of air conditioners

There are various models of air conditioners on the market, differing in installation methods and available functions. According to the principle of operation, there are two types of devices:

• An inverter air conditioner inverts AC to DC, and then the system generates a current of the required frequency, increasing or decreasing the speed of the engine.
• The non-inverter type device controls the temperature by cycling the compressor on and off. This system is cheaper, but it is also more difficult to set up.

An example of a wall-mounted type are split systems and multi-systems.The noisy main part is attached to the outside of the building, while the inside remains indoors. She is responsible for the air supply and its cooling / heating before entering the room. It also has filters.

A multi-system differs from a split-system by the ability to connect several air conditioners to one outdoor unit at once.

Minus: in the event of a breakdown, all available devices will simultaneously fail.

Scope of application: offices, apartments.

The window air conditioner is installed in the window opening: one part is outside, the other is inside. Consumers like it due to its low price and ease of installation, but older models make a lot of noise. Modern devices are free from this problem.

Recommended for residential installations.

Floor type air conditioners are made in the form of a monoblock. It is easy to mount the device and move it between rooms. Suitable for home and garden.

The disadvantages are the high cost and loud noise during operation.

In industrial and office buildings, duct type air conditioners are often used. They are attached to the ceiling, channels depart from them, through which fresh and clean air will enter several rooms at once.

The cassette type differs from the channel type in increased power and the ability to serve more rooms.

The column conditioner is intended for trading floors, restaurants, warehouses. Due to the large dimensions, it is installed exclusively on the floor. It is convenient that it is not necessary to specially prepare the room for installation.

Multi-zone VRV and VRF systems are used in large enterprises where precise temperature control is required. Appearance fades into the background, the main thing is the usefulness of the device.

The tool needed to install a split system

For work you will need:

• Electric perforator with several types of chisel. It is useful for drilling the main wall;
• If the walls in the apartment or house are concrete, then an armature detector will be needed so that when drilling the wall, it does not get into the armature;
• Pipe cutter for sawing pipes for refrigerant. Other improvised means for cutting will not work, since metal chips can get into the gap, which can have a detrimental effect on the operation of the air conditioner;
• Special set for expanding pipes. Only its use can guarantee perfect sealing;
• Reamer. Used to clean the ends of the pipe;
• Using a manual bicycle pump, the degree of tightness is checked;
• Vacuum pump. It will be needed before vacuuming the split system. It ideally removes moisture from the system, which can adversely affect the operation of the compressor;
• pressure gauge;
• Tester and phase indicator.

It is better to purchase a copper pipe with a margin so as not to waste extra time on additional trips to the store. The end of the tube must be rolled by the manufacturer, the tube must be perfectly flat.

About multi split systems

Multi system air conditioners are of the following types:

• fixed;
• Typesetting.

A fixed variant means that it is already staffed. Typically, stores sell sets of one outdoor unit and three indoor units.
The outdoor part has a limited number of ports for connecting the line from the indoor unit. Each model differs in its performance and characteristics.The outdoor unit, which is mounted outside the premises, is equipped with one or more compressors at the same time.

The type-setting type, unlike the previous version, can interact with a large number of indoor units. Some manufacturers allow you to connect up to 16 trunks at the same time.

Inverter multi split systems are another type of mechanism. The name means that the user can adjust the speed of the compressor, which saves several times the consumption.

Air conditioners also differ in the way they are placed, that is, there are the following types:

1. Floor-to-ceiling;
2. Wall mounted;
3. Mobile, etc.

Types of multi-split systems

Channel multi-split system, for example, is not mounted on the wall, as is usually the case, but directly into the air duct.

Varieties and equipment

Systems are conditionally divided into fixed and type-setting. The first is sold as a ready-made kit of 2-4 indoor units and one outdoor unit. The fixed system in the outer part has a certain number of inputs for communications and connection of internal components. The outdoor unit can be equipped with one or two superchargers, on which the performance of the system depends. Indoor equipment is always equipped with only one such device.

Modern systems with two compressors allow you to configure different modes of operation on the indoor units. Each device will work independently of the other. This possibility is inherent only in fixed types of systems.

Stacked multi-split systems can include up to 16 indoor units. The circuit splitter, to which the cooling liquid goes, allows you to connect them all to the outside of the structure.The outdoor section can have up to 3 blowers that work together. The operating conditions for this type of systems do not differ from fixed ones. You can either heat the air or cool it down.

Cool mode can be combined with dehumidification. They are similar, so it is safe for the system. It is noteworthy that you can install any number of indoor units, all restrictions are due to the power of the external section. The type of the interior is selected according to the parameters of each room individually.

The stacking system can consist of different types of external sections. Combinations are possible with any number and configurations. There are several types of internals.

1. Wall. Most home appliances look like this. The most common and most accessible type.
2. Floor and ceiling. Visually resemble batteries and can be installed both above and near the floor.
3. Simple ceiling. It looks like a kitchen hood.
4. Cassette. Are mounted during repair directly in a ceiling. The advantage is that air is supplied immediately in 2-4 directions.
5. Channel. Like the previous type, it is mounted during repairs. Air enters the room through the grate.
6. Columned. Allows you to regulate the microclimate in a large room.

Each set has control panels. One is configured as a master and is intended for system debugging and management. All others are assigned the status of "slave". The main controller allows you to set the mode for all indoor sections. The rest are designed to adjust the temperature on each air conditioner.

Usually, a fixed multi-split system is enough for an apartment. For a large private house choose suitable sets

It is worth noting that some types of blocks are installed at the stage of rough repair work, so it is important to think over this aspect in advance.

Installation Requirements

The outdoor unit is recommended to be installed on a blank wall without windows.

Installation of a multi-split system begins with choosing a place to install an outdoor unit. The length of the line through which freon will circulate separately to each internal hair dryer should not exceed the allowable values ​​indicated in the manufacturer's instructions. Otherwise, the efficiency of the climate system will not correspond to the declared one.

The compressor must not be installed in enclosed or semi-enclosed rooms, because it will often overheat and shut down due to lack of air to ventilate. This leads to premature wear of the equipment.

If the installers insist on the open installation of main pipes, explaining this as a convenience for subsequent repairs, ask them to install expensive high-quality pipes with a 30-year warranty period and install them into the wall. Pipes will fail faster if they are subjected to regular temperature changes.

A powerful multisplit is a noisy device. Mounting it on a wall with windows is not recommended.

You also need to consider:

• the arrangement of furniture in the room so that the flow of cold air is not directed at the sleeping person, and the noise level;
• dripping condensate should not fall on passers-by, the tube goes down so that there is no stagnation of water;
• the system must be connected to a separate shield and have its own wiring;
• there should be no thermal contact between the cold and warm zone;
• the external module must be mounted below the internal ones so that there is no electricity overrun.

Location of MSS

The outer part of the MSS is located outside the refrigerated space. To be more precise, it is hung on the facade of buildings, installed on the roof, it can also be placed on a balcony (loggia), in corridors of general importance, and so on. The inner and outer parts of the MSS are interconnected by pipes with freon and a drainage line. In addition, they are connected by an electrical wire.

The external part includes compressor, fan, condenser, etc. Inverter multi-split systems often include electronic components, and the installed compressor allows you to reduce the noise in the room during the operation of the air conditioner.

The MCC interior housing can be placed on the ceiling, installed on the floor, hung on the wall of a room, or embedded in a false ceiling.

Installation of a multi-split system is best entrusted to professional people who have the skills to work with air conditioners of this type. You can install the system with your own hands, for this you need to study a lot of different literature, including the user manual that is included with the MCC, and purchase all the necessary tools.

Air conditioners and split systems

Devices that create a microclimate have a common name - air conditioners. Let's talk about the difference between air conditioners and split systems. Air conditioners can be made as a single unit or divided into indoor or outdoor parts. In the first case, mobile or window air conditioners are usually used. The former can be moved indoors, but they have bulky pipes to move air.Window windows are installed in one block so that one side is located inside the room, and the other - from the outside. They occupy part of the window opening and create noise during operation.

Split systems are divided into two blocks (compressor-condenser and evaporator), interconnected by tubes and electrical wires. The noisiest part of the split system is located outside.
 

The use of such devices is fresh air and comfort.

There is also a difference in terms of design. Window and mobile units are bulkier, and split system interiors come in a variety of shapes and colors and can often be mounted on walls, floors, or ceilings without disturbing the design of the space. Another difference is the possibility of not only cooling, but also heating the air.

Split system is more difficult to install. However, it offers more features and is more economical than conventional air conditioners.

Split systems are often installed in hotel rooms, what it is and what it is for - let's try to understand this in more detail.
 

The essence of work and the principle of operation

The main purpose of a split system is to cool the air inside the room. The unit consists of two parts. One of them is installed outside the room, and the other - inside. To connect them with a narrow pipe, a hole is made in the thickness of the wall. The principle of operation of split systems is approximately the same as that of refrigerators.

The refrigerant circulating through the tube inside the system absorbs the heat of the air that is inside the room, moves the heat energy outside and returns it to the environment. The refrigeration circuit of an air conditioner consists of two main elements: a condenser and an evaporator.

The first of them is enclosed in the outdoor unit of the device, and the last one is in the unit that is installed in the room.

The main elements of a split system are a condenser, a compressor and an evaporator, between which a refrigerant circulates, moving heat energy from the room to the street

The refrigerant (usually freon) moves between devices in a closed loop. Inside the room, it heats up in the process of absorbing thermal energy and becomes a gas.

Thus, the air is cooled as it passes through the evaporator. To improve the movement of air flow throughout the space of the room, a fan is used.

The refrigerant then enters the condenser. Here it passes through a compressor and then cools down in contact with colder outdoor air. The refrigerant becomes liquid again.

The principle of operation of such a system corresponds to the operation of a conventional refrigerator; the ability of freon to evaporate at low temperatures is also used here.

Important Aspects

It is logical that for help in installing air conditioners, and even more so multi-split systems, you will have to seek help from specialists. Because of the ozone depleting refrigerant gas they use, as well as other air conditioners, they must be installed efficiently and effectively. The indoor units should be installed as close as possible to the ceiling in each room. Cool air is heavier than warm air, so for maximum cooling efficiency, you will need to set the louvre blade correctly. Exactly the same as for the highest quality heating.
In addition to all this, you must consider other features before proceeding with the installation or even the direct selection of a multi-split system.We will list some of the main aspects below.

Accommodation

When you install a split air conditioning system, you need to make sure that the wall you choose is strong enough to support it. If you choose a less secure wall in your office or home, you will find that once installed, the outdoor unit can simply collapse and leave the wall damaged. Not to mention the losses in case of damage to the air conditioner itself. The installer will need to initially check the chosen wall to see if it is strong enough to install the indoor unit. And as we noted earlier, it is best to place it almost under the ceiling.

There should be at least 15 centimeters of free space on three of the sides of the indoor unit. It will allow air to flow and circulate throughout the room properly. All of these are critical to the efficiency of an air conditioner. Be sure to consider all these aspects and make sure that everything is done incorrectly during installation.

Location

For adequate cooling and operation of the multi-split system in general, it is important that you shield the outdoor unit from direct sunlight or water. If you plan to place one of the indoor units outdoors, then it will not be superfluous to make sure that there are no obstacles in the way of the heat coming from the condenser

The outdoor unit must also be placed on a flat surface, otherwise it will vibrate excessively.This vibration can break many important components of the unit, and it also creates a lot of unwanted noise that will disturb you and your neighbors.

Correct inclination

Indoor units of multi-split air conditioning systems should also be installed at a slight slope. Proper slope will allow an unrestricted flow of condensed water to run down the downpipe. Although you may deviate a little from the correct trajectory, this is one of the most important aspects for ensuring the full and efficient operation of the air conditioner.

Price

Costs are another item to keep in mind. Initially, the purchase and installation of a multi-split system can be expensive, especially if there are a large number of rooms. At the same time, the service itself is much cheaper, which is generally nice. However, do not forget that in the future you may need to add new blocks to the system, and this is an additional cost. The same can be said about electricity bills. True, if this is some kind of hotel business or enterprise, then bills are the last thing that will worry you.

Guarantee

One of the last aspects when installing a split system is the warranty. After all, as we have already found out, if the external unit fails, then the entire system will not be able to function.

No matter whose fault this happens, you must be sure that you are provided with the maximum guarantee, both from the seller and from the installers. Otherwise, this will result in yet another unforeseen cost, which can be safely attributed to the previous paragraph.

How to connect the air conditioner to the mains

There are two common ways to connect an air conditioner to mains power:

• through a socket for single-phase household appliances;
• from a separate line mainly for industrial devices.

with socket

Powering a split system using a plug and socket is the simplest way that does not require preparatory electrical work. This option is chosen for air conditioners built into the window, low power systems up to 4 kW, as well as for temporary use. It must be remembered that the outlet for household air conditioning must be strictly individual.

The connection can only be made if there is experience in electrical work with household appliances. The algorithm of actions will be as follows:

• prepare materials and tools;
• study the diagrams in the instructions;
• lay and connect interconnect cables (this was described above);
• install an outlet.

Before a test run of a split system, you need to check the circuit for correct connection.

The socket must be with copper wires and connected to the shield in accordance with all electrical safety rules.

Direct network connection

A separate power line is best suited for a powerful split system. In this case, you need to make sure that it is possible to connect additional equipment to the electrical panel (necessarily grounded). The option of direct connection to the network does not load the working lines of the network: the power is supplied directly to the indoor unit of the air conditioner.

The cable is laid along the prepared strobe in the wall or in a box along the wall surface. To the shield, the cable is pulled through the machine with the calculated power, which will be discussed in detail in the next subsection.The cross section of the wire will depend on the power of the device and the distance of its location from the shield.

The connection instruction otherwise repeats the first method. This method allows you to install the air conditioner anywhere in the house.

Split system - what is it

Air conditioning systems are divided into two main categories: directly air conditioners and split systems. The difference between them is quite simple: in the first, all the units are located in one building. In the second, the compressor, fan and evaporator are located in one unit, which is called external, because it is installed outside. And the hair dryer, which supplies air to the premises, and, accordingly, the second evaporator through which the refrigerant passes, are located in a separate unit. It is installed indoors, which is why it is called internal.

Between themselves, the blocks are connected by tubes through which the refrigerant passes, and by wires connecting control unit in the indoor unit and other equipment in the external. It is this block division that is called a system. And the word split or from English "split" means to separate. Therefore, when they talk about split air conditioning systems, they understand two blocks separated by a wall.

Principle of operation

The principle of operation of a split system is based on the property of some liquids to release heat when they begin to condense from a vapor to a liquid state, and absorb it if everything happens the other way around. Therefore, first of all, it is necessary to deal with the configuration of the equipment itself, that is, to determine which devices and units are part of the split system, and what each of them is intended for.

It must be understood that the movement of the refrigerant will be carried out through the supply and exhaust channels connecting the two units to each other. In this case, evaporation will occur in one block, and condensation will occur in the other. Do not forget that all processes are under the vigilant control of the control unit, which contains the functions of controlling the fan, compressors and hair dryer.

Device

As already mentioned, all the main units are located in the external unit:

• a fan with which the condenser is blown in the outdoor unit;
• a compressor that compresses freon so that it moves through the system;
• the evaporator (it is also a condenser in the form of a radiator), evaporation occurs inside it, that is, the transition of freon from a liquid state to a vapor state;
• thermostatic expansion valve (TRV), which reduces the pressure of the refrigerant before it must go to the indoor unit.

In the indoor unit of the split system there is an evaporator, where the freon turns back into liquid, and a hair dryer, which blows the evaporator. Today, many manufacturers provide indoor filter unit fine purification, which purifies the air of dust, tobacco smoke, some varieties of bacteria and viruses. It can include three different filter elements: electrostatically charged filter, carbon fiber and disinfectant. That is the order in which they are installed. This filtration system ensures that there will always be clean air in the room, because the installed filters can pass particles no larger than 0.001 microns through themselves.

It must be understood that the air conditioning system itself is a scheme for the serial connection of some units into a single circuit.That is, the entire network is assembled into a kind of refrigeration circuit. It includes four main devices: compressor, expansion valve, condenser and evaporator indoor unit.

The system works like this:

1. The refrigerant gas moves from the evaporator to the compressor. Its pressure is 3-5 atm., temperature is within 10-20C. Here, freon is compressed to 20-25 atm., which means that its temperature immediately rises to + 90C.
2. In this state, it enters the condenser, which is blown by a fan. And since the temperature outside is always lower than the temperature of the refrigerant, the latter begins to turn into a liquid, that is, condense with the release of heat. The temperature drops to + 10-20C, and the pressure remains the same.
3. Now it is necessary to lower the pressure to 3-5 atm., for which the expansion valve is used. Here, not only the pressure drops, but the temperature drops again, and part of the freon evaporates.
4. After that, the refrigerant with a reduced temperature and pressure passes into the evaporator in the indoor unit, which is blown by a hair dryer. And the process is repeated.

Air conditioner operation

All components of the unit are connected to each other by copper pipes and thus form a refrigeration circuit. Freon circulates inside it with a small amount of compression oil.

The air conditioner device allows you to perform the following process:

1. A refrigerant enters the compressor from the radiator at a low pressure of 2-4 atmospheres and a temperature of about +15 degrees.
2. When working, the compressor compresses freon to 16 - 22 points, in connection with this it heats up to +75 - 85 degrees and enters the condenser.
3. The evaporator is cooled by an air stream that has a temperature lower than that of freon, as a result of which the refrigerant cools down and is converted from a gas to a watery state.
4. From the condenser, freon enters the thermostatic valve (in household appliances it looks like a spiral tube).
5. When passing through the capillaries, the gas pressure drops to 3-5 atmospheres, and it cools down, while part of it evaporates.
6. After the expansion valve, liquid freon enters the radiator, blown by air flow. In it, the refrigerant is completely converted into a gas, takes away heat, and therefore the temperature in the room decreases.

Then freon with low pressure moves to the compressor, and all the work of the compressor, and hence the domestic air conditioner, is repeated again.

Operation of the air conditioner in the cold

What is a multisplit system?

Multisplit air conditioner differs from the standard version due to its features. If you recall, the usual version consists of two blocks, but the considered version has one external block, to which several internal elements can be connected at once.

multi split systems

This principle is implemented in cases where, for some technical reason, the installation of a conventional air conditioner is not possible. The advantage of this approach is that you do not need to pick the walls in each room and spend money on buying another external element. The indoor unit does not lose functionality at all.

If we talk about the cost, one interesting fact should be noted. Of course, the presence of only one external unit immediately reduces costs, but it is precisely in it that the main cost lies, because expensive automation is introduced into it to service several elements.

Advantages and disadvantages

A multi-split system is more complex than a conventional air conditioner. In the latter, one outer block is mapped to one inner block. And in a multi-split, the outer section implies the use of a large number of internal ones.

The main advantages of such systems.

1. You can install blocks in different rooms. It is possible to choose the appropriate section for a particular room and not overpay for the standard one.
2. In each room you can set up an individual microclimate. For example, you can raise the temperature in the bedroom, and lower it in the kitchen.
3. Multi-split works quietly. The sound comes only from the outdoor unit, which can be moved away from the windows of the living quarters. It should be noted that in simple air conditioners, the installation of blocks is always linear, which means that it will not work to reduce the noise level.

The multi-split system also has disadvantages.

1. The inner blocks will not work if the outer one breaks.
2. You can set different temperatures in different rooms. However, the heating or cooling mode is set on the outdoor unit and cannot be changed.
3. For installation of the system, you need to invite experienced craftsmen with the appropriate tools. You cannot install the system yourself.
4. The cost is much higher than conventional air conditioners.

Varieties of air conditioning units

The arrangement of indoor and outdoor modules of all "splits" is the same, with the exception of some small things. The units are divided into types according to the method of placing the indoor unit:

1. The most common are wall-mounted. From the name it is clear that the module is hung on the wall inside the room.
2. Channel (unframed) models are built into the rectangular air ducts of the air conditioning system of a private house.
3. The cassette blocks are fixed to the ceiling, the cooled air is supplied in 4 directions from top to bottom. The body of the unit is hidden behind a false / stretch ceiling, the bottom panel remains visible.
4. The column-type module is placed on the floor in a convenient place. The name comes from the shape of the unit - a narrow high body resembles a column (shown above in the photo).
5. Flattened ceiling blocks are mounted to the ceiling. Do not need additional cladding with suspended ceilings.
6. Floor versions are fixed to the wall at a height of 10...30 cm from the floor according to the manufacturer's instructions.

Special mention deserves multi-split systems, consisting of one outdoor powerful unit and 2-4 indoor ones. Such ACS is capable of maintaining different temperatures in several rooms and is used in exceptional situations when it is impossible to place 2-3 separate modules on the facade of a building.

• higher price of equipment with the same installation cost;
• an external multiblock does not allow simultaneous cooling and heating of two adjacent rooms; operation is allowed only in one mode;
• the outdoor unit differs in size and decent weight;
• the cost of service increases due to the increased volume of freon and the complex arrangement of the unit, which can contain 2-3 compressors.

In large shopping centers and industrial buildings, industrial split systems are used - central and rooftop roof-top air conditioners. In them, the blocks are also separated - inside the premises there are fan coil units, supply units, outside - modules for cleaning, heating and cooling (chillers).

Review of the best brands

Modern manufacturers offer a wide range of multi-split systems.When choosing, you should give preference to well-known companies that are included in the rating of well-established among consumers.

Toshiba. The Japanese company has been manufacturing home appliances for over 120 years. The release of air conditioning systems is one of the main profiles. The first split system came out of the Toshiba factory. Devices of the middle price segment have a nice design and many additional options. Most users note the reliability of the systems.

Separately, it is worth highlighting such companies as Dantex, Shivaki, Hyundai, Pioneer. Economy representatives. Production is located in China, manufacturing involves the use of quality materials and advanced technologies. The range of these companies is not inferior to more expensive counterparts.

Affinity with heat pumps

The device of the inverter split system and the air heat pump (HP) is identical. Both units use the principle of a refrigeration machine, take the heat from the outside air and heat the inside. Differences in design - in order to increase efficiency, the area of ​​​​the external heat exchanger-evaporator HP is significantly increased, so the unit is often placed on the ground, as shown in the photo below.

Geothermal pumps that extract heat from the ground are also structurally close to split systems. The difference is in the method of taking and transferring heat to an external evaporator - here, instead of outside air, a non-freezing coolant is used, flowing through loops of underground circuits. The main operating cycle is identical - brine or antifreeze evaporates freon in the heat exchanger, which gives off heat to air or a water heating system.

Conclusions and useful video on the topic

What is a multi-split. Block layout. Features of installation work.

Installation of the system in 2 stages - before repair and after it.

If there is no possibility or desire to install two separate air conditioners, it makes sense to choose a split system for two rooms. Important parameters when choosing are power, temperature range, length of freon pipelines, height differences between blocks.

Share with readers your experience of choosing and using a split system for two rooms. Please leave comments, ask questions on the topic of the article and participate in discussions - the feedback form is located below.