DIY fan coil: fan coil for installation and repair

Installation features

Taking into account the complexity of fan coil-chiller systems, its installation and adjustment should be carried out by highly professional specialists. Only they will be able to perform high-quality installation of fan coil units by making competent:

• installation of the unit in the place where its work will be as efficient as possible;
• assembly of piping units by installing the necessary taps, valves, temperature and pressure control devices;
• laying and thermal insulation of pipes;
• installation of a condensate drainage system;
• work on connecting devices to the mains;
• pressure testing of the system and checking its tightness;
• media (water) feed.

They will also make all the necessary calculations before starting work, taking into account what functional load this or that fan coil will perform, as well as the features of each room in the structure.

Thus, you were able to make sure not only that the fan coil-chiller systems are very effective, economical and reliable, but also that they require complex installation and commissioning operations. And this requires the involvement of employees of organizations specializing in the creation of such turnkey systems.

Principle of operation

A chiller, which is an air conditioner, heats or cools the coolant entering it. It can be water or other non-freezing liquid. Then, with the help of pumps, the liquid is pumped into the system and is transferred through pipes to the fan coil units.

This device receives air from the room, which is mixed with the help of a fan with the air inside the unit, already heated or cooled.

After this operation, the air mixture is released into the external environment. This is how the premises are air-conditioned using a chiller-fan coil unit.

Unit diagram

The chiller heat exchanger is connected to the pump and storage tank. The expansion tank is also displayed on the pump. Through the pipeline, through a system of control valves, the coolant is supplied to the fan coil units.

High-quality ventilation in a private house with your own hands diagram, instructions and recommendations. Read about the benefits and dangers of humidifiers in private homes.

Read how to install an air conditioner with your own hands at https://klimatlab.com/ventilyaciya/kondicionirovanie/ustanovka-kondicionera-svoimi-rukami.html

Design features

The main feature of the system is that a chiller-fan coil project is developed individually for each building. For example, the design of one building does not allow the chiller to be placed anywhere other than on the roof. And the other is built in such a way that the main device of the system can only be located in the attic.

In addition, the development takes into account the requirements for the microclimate created in the premises, their purpose, the infrastructure around the building.

The chiller, its type and modification, is selected in accordance with the specified requirements, the number of fan coil units is also determined, how the system will be used, the intensity of its operation, what its mode will be, whether the air will be cooled or, conversely, heated, or both , and the other together.

How do these devices work?

Principle of operation

The air drawn by the fan through the fan coil heat exchanger is heated or cooled, depending on which operating mode is selected. In this case, the air flow is created not from the air mass that is present in the room, but from fresh air supplied from a special machine - a chiller, which is the central unit when creating an air conditioning system or heating all rooms in a building using fan coils. The air enters the chiller from the air supply unit, which produces air intake from the street.

What is the advantage of such a centralized air conditioning system?

Renovation work

Fan coil units must be repaired by qualified specialists.

Recovery measures are carried out in case of serious equipment breakdowns.

Compressor does not work

Actions depending on the breakdown:

1. Switch defective: find cause or replace.
2. Fuse blown: replace.
3. Refrigerant leaks: locate the leak, seal and top up.
4. There is a lot of fluid in the system: measure the pressure and remove the excess.
5. Gas appears in the fan coil unit: release and restart the system.
6. Air inlet obstructions: inspect fan for dirt.
7. The compressor is overheating. If there are problems with the bearings, it must be replaced. Other reasons: frequent activation, insufficient lubricant.
8. Electrical problems - high or too low voltage: fix.

The device must be inspected by several specialists. Do-it-yourself fan coil maintenance can lead to complete failure of expensive equipment due to incompetent intervention in the repair process.

Incorrect installation and selection of the location of the chiller leads to frequent repairs and unnecessary maintenance costs.

The chiller is a unit weighing from 400 to 5000 kg, depending on the capacity, so the team is forced to carry out maintenance on site. The price in this case is much lower, because dismantling and transportation are more expensive than the repair itself.

Fan breakage

Repair technical work in case of fan breakdown:

• replacement;
• cleaning the impeller;
• centering, if the wings cling to adjacent parts;
• repair of the electrical component of the fan.

The prices for the repair of the fan are determined by the degree of breakdown and the need for transportation to the service.

Repair of cassette and channel fan coil units

Cassette fan coil units require periodic replacement of curtains and electric drives, adjusting the direction of the air flow. Contamination on the cassette is eliminated twice a year to ensure free passage of air to the heat exchanger.

It will be more expensive to repair a ducted fan coil unit, since the system is hidden behind a false ceiling. The work requires the dismantling of the ceiling structure to provide access to the units located in the room. The process takes longer and requires additional tools, as well as restoring the integrity of the ceiling after inspection or repair.

Varieties of fan coil units

Today, there are four main types of such equipment:

1. Cantilever frameless.
2. Console in the case.
3. Horizontal.
4. Fan coil unit cassette.

Depending on the installation, each type of this climatic equipment can be wall-mounted, floor-mounted, ceiling-mounted or built-in. Depending on the tasks, fan coil units can be equipped with two or four-pipe piping. When using two-pipe piping, the device can only work for cooling or heating the air in the room. The use of a four-pipe piping allows you to use both a cold and a hot circuit of the chiller, while operating the unit for both heating and cooling, making settings from the control panel. Due to the complexity in implementation, the cost of installing fan coil units with a four-pipe piping is significantly higher than with a two-pipe piping.

Fan coil units in air heating systems of private houses

Ecology of consumption. Manor: One of the most modern heating and air conditioning systems for private houses is the chiller-fan coil system. This system will allow you to create a favorable microclimate in your home, maintain fresh air, and preserve the health of the household.

One of the most modern heating and air conditioning systems for private houses is the chiller-fan coil system.This system will allow you to create a favorable microclimate in your home, maintain fresh air, and preserve the health of the household. This system especially stands out against the background of traditional split systems, therefore, we will talk about its features in this article. First, we will consider the structure of the system as a whole, then we will directly touch on the fan coil units.

The main purpose of the chiller-fan coil system is air conditioning. It consists of two main parts: a chiller and a fan coil unit. A chiller is a device that is directly responsible for heating or cooling, and a fan coil is essentially an air conditioner that serves to cool or heat the air in the room in which the fan coil itself is located.

Unlike a conventional air conditioner, refrigerant does not circulate through the fan coil unit, often water or non-freezing liquid circulates through it. As for the chiller, it can work, for example, on solid fuel or work on a heat pump system.

In addition to the main parts, the system contains: a hydronic module, automation, connecting elements, storage and expansion tanks, heat carrier and refrigerant. A hydronic module is, in fact, a pumping station, whose task is to ensure the movement of the coolant in the system. Automation provides control and regulation of the system during its operation.

Connecting elements are pipes that connect parts of the system, units, to each other. Ethylene glycol (for regions with cold or temperate climates) or water (for regions with hot climates) is used as a heat carrier. The refrigerant is gas, often freon.

Distinctive advantages of the chiller-fan coil system are in a number of its features.

Firstly, the system is very easy to maintain - filters can be easily removed, cleaned or changed.

Secondly, it is possible to install several fan coil units (in separate rooms), while the chiller operates one for the entire system, and the number of fan coil units is determined only by the chiller capacity.

Thirdly, the chiller is installed at once in one specific place, it does not require several places, that is, it does not eat up a lot of area.

Fourthly, well-organized thermal insulation of pipes will allow the transfer of the coolant over a long distance, that is, heated or air-conditioned rooms can be located far from the chiller.

During installation, ordinary pipes, standard shut-off valves, typical automation are used. The system is ecologically safe, if the solution of ethylene glycol in water and has some toxicity, then if it leaks, a person will instantly start coughing and leave the room - he will be safe. As for the refrigerant, it circulates only in the chiller, that is, in the unit in the attic or on the roof - outside the living quarters. Such a system allows you to combine both heating and supply and exhaust ventilation at a relatively low cost of installation.

The coolant entering the chiller is heated or cooled, just like in an air conditioner. Water or an antifreeze liquid serving as a heat carrier is supplied to the fan coil units by means of a pumping module, where the room air is mixed with the air of the unit, using a fan installed inside.

A heated or cooled coolant gives or takes away heat from the air in the room, so the correct microclimate is achieved. This is the principle of operation of chiller-fan coil systems, which perfectly show themselves as air heating systems for private houses.

The heat exchanger of the chiller itself is connected to the pump and the storage tank (accumulator), then an expansion tank is installed, and then the coolant is fed through the pipes to the fan coil units, while the control valves installed in the pipeline adjust the system to the correct mode.

For a particular house, the project of the system is developed by specialists individually, and if somewhere the chiller can be installed only on the roof, otherwise the attic is best suited for placing the chiller. When designing, take into account all the features of the premises, the backyard infrastructure and the requirements of households for the microclimate.The chiller type is selected individually, as well as the number of fan coil units, depending on the load intensity and on the individual customer's requirements for the peculiarities of the system operating modes.

The devices included in the system can work together or separately, again depending on the type of system. Chillers are reversible, steam compressor or absorption chillers. The reversible chiller is capable of both heating and cooling. The steam compressor will remove heat from the coolant circulating inside the unit into a special chamber.

And the absorption can, by changing the state of aggregation of the liquid, take away heat from it, or vice versa - heat it; the absorbent transfers heat to the consumer. Cooling can be air or water, and the cooling circuit is remote. Directly fan coils are cassette or duct, wall, floor or ceiling.

When choosing a system, it is important to evaluate the following parameters: chiller capacity, fan coil capacity, pumping station capacity, pipeline length, pipe insulation. So the chiller-fan coil system can be designed for any building, not only for a private house, but also, for example, for a supermarket or hotel. published

P.S. And remember, just by changing your consumption - together we are changing the world! © econet

Classification

You will be able to determine for yourself which devices are most suitable for you for installation, knowing their parameters and performance characteristics.

Currently, you can choose from four different fan coil designs:

1. Console type.
2. Console type in the case.
3. Cassette type.
4. Horizontal type.

All these types of heat exchangers can be installed in a room in a variety of ways:

• hang on the wall;
• to be installed simply on the floor of the room;
• be built into the ventilation system of the building;
• installed in suspended ceiling structures.

The main characteristics of a fan coil unit that affect the choice of a particular device are:

• cold air performance;
• overall air capacity.

Connecting a cassette fan coil unit

In addition, heat exchanger systems using water as a carrier can be:

1. Two-pipe. This strapping scheme is the simplest and most common. It only allows you to cool the air in the room. Therefore, the cost of such a device will be low. In winter, two-pipe fan coil units can be switched to heating mode, but for this the pipes must be disconnected from the chiller and connected to the central heating system. This function is performed by a special manually adjustable valve.
2. Four-pipe. This system includes two heat exchangers, one of which is connected to the chiller, and the other to the hot medium system (central heating system). This strapping scheme is more complex. Therefore, the price of such a fan coil will be higher. This system allows you to either cool the air in the room or heat it without making complex switching of pipes, but only by selecting the required mode on the control panel of the device. Such fan coil units are best installed in the area of ​​windows, since this will compensate for heat loss through the glass.

Main advantages of the system

The duct fan coil unit has a lot of advantages, among them it is possible to highlight the provision of full cooling or heating of the room within five minutes after starting the system. This possibility is guaranteed by the method of simultaneous installation of a fan coil unit and a chiller. Among other things, the system allows you to create a comfortable microclimate in the rooms where the fan coil unit is installed. The owners of an apartment, house or building will be able to save energy.

Additional features include the ability to connect a different number of fan coil units to the chiller. But the step of the route from the chiller to the most distant fan coil unit cannot be more than six hundred meters. A duct-type fan coil unit allows you to save money that is required to create pipe routes when choosing water as a carrier.

Chillers and fan coil units for central air conditioning systems

A chiller-fan coil unit is a type of air conditioning device, a distinctive feature of which is the circulation between blocks of water (ethylene glycol / propylene glycol) as a refrigerant.

Chiller is a refrigeration machine that lowers the temperature of the liquid inside the coolant. Installed on the roof, attic space, technical room. When installing the machine on a roof, you must drain the water from the system before the onset of the cold season.

Fan coil is an internal unit of the device equipped with a fan (fan), a heat exchanger (coil). Outwardly, it is very similar to a split-system block.

The equipment can operate in three modes: cooling, heating, cooling-heating (4-pipe piping).

Indoor unit modifications:

• wall
• cassette
• duct
• floor and ceiling.

Let's briefly present the installation diagrams.

Stages of installation work

Installation of the chiller-fan coil system is carried out in the following sequence:

1. The chiller is installed in a technical room or on the roof.
2. The installation site is determined according to the plan. The indoor unit case is fixed to the wall, ceiling or ventilation.
3. The units are connected to air ducts. For duct models, valves are installed that regulate the supply of fresh air.
4. The piping units are assembled near the fan coil units, sensors and taps are installed.
5. Pipes are laid and thermal insulation is done.
6. The drainage is discharged into the sewerage system.
7. The system is connected to the mains.
8. First start-up and tightness test - pressure test.
9. Filling pipes with coolant and final testing of the facility.
10. Drawing up an act of completed work.

Dismantling is carried out in the following sequence:

• overlapping nodes near fan coil units;
• disconnection from the water supply system;
• overlapping drainage;
• disconnection from the network.

If you plan to replace fan coil units, the pipe diameters of the old and new systems are taken into account.

Types of installation of fan coil units

The basic diagram of a fan coil unit provides:

• the presence of a pipeline that transports hot or cold water, depending on the tasks in a certain period of time - winter, summer;
• the presence of a chiller that prepares the required water temperature and creates a flow of fresh air taken from the street;
• internal devices (fan coils) through which the room temperature is controlled.

Internal climatic devices:

• Cassette. Installed behind false ceilings. Suitable for large areas in shopping centers, industrial premises.
• Duct. Found in ventilation shafts.
• Wall mounted. A good choice for small spaces - apartments, offices.
• Floor and ceiling. Suitable for placement under ceilings or near walls.

Installation of chillers and fan coil units of various types has its own characteristics, as well as advantages and disadvantages:

• The duct is capable of performing three functions (cooling, heating, ventilation), but it requires accurate calculations of the consumed air volume, expert advice in terms of installing a water heating system for the winter period.
• Installation of cassette-type fan coil units saves space, air conditioning large rooms, but requires space under the ceiling, which is allocated for the installation of the unit.
• Installation of floor-standing fan coil units makes it possible to quietly cool rooms of complex design, without affecting human health, but requires more power and space on the floor or under the ceiling.
• Connecting a wall-mounted fan coil is the least economical way, but easier.

Systems are two-pipe and four-pipe. The price of a four-pipe wiring is higher, since it simultaneously performs both heating and cooling. The two-pipe system is cheaper, but for the heating function it will be necessary to divert the pipes from the refrigeration unit and connect to the boiler during the heating season.

Duct fan coils are mounted using the hidden connection method. The section in the ceiling must be movable to access the device.

Cassette, floor and wall units are mounted in an open way. Open type devices are easier to operate and maintain.

Fan coil housing installation

There is only one possible installation method for each fan coil model:

• Units for floor mounting (console) are installed on special racks. The enclosure is fixed to the wall with flat head screws.
• Wall-mounted vertical installation involves drilling technical holes according to the template supplied with the equipment. Dowels are inserted into the holes, then the screws on which the fan coil is hung.
• For ceiling mounting, the unit is almost always installed behind a false ceiling. In order for the decorative panel to protrude flush with the suspended structure, the enclosure is attached to the ceiling slab by means of anchor bolts and mounting rods or similar bolts and brackets.

Stages of installation work

Fan coil installation works can be roughly divided into several stages:

1. The correct choice of installation site.
2. Fastening the device to the enclosing structures.
3. Creation of a strapping node.
4. Laying of a pipeline for supply and discharge of working fluids.
5. Installation and connection of the drainage system.
6. Connection of power supply and control system.
7. Checking the tightness of the system.
8. Setting up work.

Despite the difference in design, the installation work of fan coil units is almost the same.

It should be understood that the quality and durability of the entire system directly depends on the competent installation of fan coil units, therefore it is best to entrust the implementation of such work to professionals

When contacting a company for the installation and maintenance of such climatic equipment, you should pay attention to the experience of specialists and the availability of the necessary equipment in the company

Installation of electrical wiring diagram for fan coil units

Wiring diagram for wall fan coil unit
Before starting work, you need to familiarize yourself with the wiring diagram. Electrical equipment must be grounded.

Requirements for connecting fan coil units to the mains:

• use the cable according to the recommendations in the manual;
• organize a separate power supply with the required voltage;
• connect all wires directly to the shield, including grounding;
• the water circuit must be on the opposite side of the terminal box;
• the elements of the hydraulic circuit must not come into contact with the wires.

The unit starts up after an insulation test. The direction of rotation of the fan impeller, the operation of the drain pump, and, if available, an electric heater are checked separately.

The act is drawn up based on the test results. At the same time, an agreement is signed with the company for continuous service.

Fan coil connection in several stages

First step

- this is the installation of the fan coil itself in the place allocated in the project with its subsequent connection to the pipeline system supplying water (or any other coolant). Again, all the characteristics inherent in the project should be taken as a basis.

• It is impossible to change or change the diameters of the pipelines, the material from which the pipes should be made, which will definitely affect the flow rate of the coolant through the fan coil and, in the future, on the operability of the chiller itself.
• Do not allow the installation of valves, adapters or other elements of the hydraulic circuit that are not provided for by the project, as well as the installation of the same elements.
• It must be remembered that when the fan coil is in operation, condensate forms on its heat exchanger and this condensate must be discharged into the sewage system.
• To avoid stagnation of condensate in the drainage pipelines during its laying, it is imperative to maintain a slope of 1 degree throughout the drainage pipeline.
• Completely eliminate failures and the formation of stagnant zones.
• There are unpleasant odors in the sewage system and the ingress of these odors through the drainage pipeline into the fan coil unit, and then into the room, must also be excluded by providing a water seal or odor-locking device on the drainage pipeline.

Second phase.

Since ducted fan coil units are of different types of location, the most difficult thing at this stage is to connect the fan coil units to the air ducts.

• Not all ducted fan coil units can be connected to air ducts, so this stage is more for those who have such a connection. If the duct fan coil requires the connection of air ducts, then at this stage such a connection is made through which air flows to the fan coil itself, and through which the prepared air enters the room after the fan coil. In addition, it is necessary to pay attention to the air duct that provides the flow of fresh air, if such is included in the project.
• The material and cross-section of the air ducts are different and therefore these parameters of the air ducts should be observed in accordance with what is laid down in the project documentation.
• Attention should be paid to the length of the air ducts through which air must flow from the room and into the room. This length is directly related to the technical characteristics of the fan coil unit such as static head. Increasing the length of the duct can lead to a decrease in the air flow rate.

Stage Three

... The fan coil units are connected to the power supply network.

• Before connecting, it would be a good idea to take some time to check the voltage match of the fan coil unit and the network to which you want to connect. The machine through which a fan coil unit or several fan coil units should be connected should be slightly larger (by about 15-20%) in current strength (amperes) than all fan coil units connected to it. You can use the formula from the 6th class to calculate the current strength of the machine. P = U * I whence I = P / U. Where P is the electrical power of the connected fan coil units; U is the voltage in the network (usually 220 V); I is the current strength (amperes) to which the machine must correspond through which the connection is made.
• We must not forget that it is imperative to connect all three wires, especially the third - ground.

You should not trust this type of work to random people who are not certified to carry out such work, thereby remembering that "a miser pays twice."
Today, in homes, instead of air conditioning systems, they often resort to installing fan coil units - devices that cool and heat the air in the room. The heat exchanger can be installed in different rooms of the building and set an individual temperature mode for each of them.

Installation

Installation of chillers and fan coil units consists of several main stages:

1. First, the device is mounted indoors.
2. Then the strapping unit is assembled.
3. Installation of pipelines and thermal insulation to them is in progress.
4. Air ducts are laid and their sound insulation is organized.
5. A drainage system is being created.
6. The equipment is connected to the mains.
7. Check the tightness.
8. Start the system.

Mounting by device type

Floor

The easiest installation process is to install a floor-standing fan coil unit without a condensate duct. They do not spoil the interior and can be installed independently.The typical design of such equipment consists of two nozzles through which the mixer and the working fluid go.

Cassette, wall and sub-ceiling

The installation of the cassette fan coil unit and the other two is a little more difficult, because they can be either two-pipe or four-pipe. However, their electrical system may differ significantly from floor systems.

Therefore, it is best to entrust the installation of a wall-mounted fan coil unit, under-ceiling and cassette, to specialists.

With the help of specialists

Connecting a fan coil is a complex process that requires a professional approach, so it is best to contact a specialist. Only they will be able to competently do the work on:

• installing the unit in the most efficient place;
• assembly of piping units by installing the necessary taps, temperature and pressure control devices, valves;
• laying and thermal insulation of pipes;
• installation of condensate drain;
• connecting devices to the electrical network;
• pressure testing of the system;
• tightness check;
• water supply.

They will do all the calculations before starting work and will take into account the characteristics of the room and the load of each fan coil. Experts will create a safe and reliable system that will serve the user for a long time.

What to remember when contacting specialists

In order to correctly select a company that provides installation services, you should pay attention to the following criteria:

• great experience;
• high-quality equipment and spare parts;
• the company carries out all stages of installation: from thermal calculation to checking the operation of the system.

It will be difficult for an untrained customer to control the correctness of the process and compliance with all requirements if he does not have special knowledge. And in the absence of knowledge about a specific model, you can easily break the device.

Fan coil installation with piping

In addition to cooling, this air conditioning system is used for heating. The indoor unit is connected to the chiller and central heating system. For this, a second heat exchange circuit is used.

Depending on this, two types of strapping are distinguished:

1. Two-pipe. Operation only for heating (the chiller is equipped with a heat pump) or cooling. The piping is organized by a two-pipe circuit with one heat exchanger. In this case, the device is equipped with a 2-way valve that works to open / close the fluid supply inside the heat exchanger.
2. Four-pipe. Connecting a device for cooling / heating at the same time. One circuit is for connection to a chiller. The second two-pipe circuit is for connection to central heating. Thus, the device simultaneously cools and heats the premises. It is relevant for buildings where a separate setting of the temperature regime in different rooms is required.

A 3-way valve is used here, which supplies liquid bypassing the indoor unit when heating is connected, which allows you to maintain the autonomy of the circuits with their own temperature characteristics.

The use of this device as part of central air conditioning equipment allows you to bring the quality of the cooled air to the required microclimatic indicators. The ability to connect to central heating during the cold season significantly saves energy costs. Especially important for large office buildings, business centers, large shopping areas. Installation for suburban housing is also possible.

Chiller-fan coil circuit operation

First of all, we will consider how a single-zone SCR for 3 units + an inverter chiller, shown in the diagram below, works. The system maintains a comfortable temperature in summer and during the fall-spring transition period. Winter heating functions effectively at -5 ... -10 degrees below zero.

Clarification.A chiller is a unit that uses the Carnot vapor compression cycle to cool / heat the coolant. The unit is placed on the street, the working fluid is R410a or R407a freon. The heat exchanger-condenser is blown by air or cooled by liquid.

The working algorithm looks like this:

1. In summer, the air-to-water chiller cools the heat carrier to a standard temperature of +7 ° C (if it is +35 degrees or less).
2. The hydronic module directs cold water to a network of fan coil units connected in a two-pipe scheme (like radiators in a heating system).
3. Using the remote control, the user sets the desired air temperature separately in each room.
4. At first, the closers reach the set temperature, operating at maximum power. Then the controller, on a signal from the sensor, reduces the cooling intensity - it gradually reduces the fan speed (in total, there are 3 to 8 steps, depending on the model).

   

5. When the air reaches the set parameters, the two-way solenoid valve shuts off the coolant supply at the command of the electronics. Then the fan coil unit maintains the temperature.
6. The water heated to 12 ° C (on average) returns to the evaporator heat exchanger of the chiller, the cycle repeats.
7. In autumn, the outdoor temperature drops, the chiller receives a request for hot water from the fan coil units and switches to heating mode. Switching is performed manually or automatically - at the command of an additional controller.

Note. Well-known manufacturers of climatic equipment Gree and Carrier indicate the maximum operating ambient temperature plus 46 ° C. In such conditions, the water can be cooled to +18 degrees.

The hydraulic module providing the coolant supply consists of a pump, an expansion tank and an executive automation unit. Elements are included in the design of the chiller or are installed separately. Units of increased power are supplied with hydronic modules for 2-3 pumps.

In inexpensive fan coil units, the solenoid valve may not be available. Then the external piping of the closer is performed - an executive three-way valve, a servo drive and shut-off valves are installed. How it works, the master will tell in the video:

In order for the single-zone system to fully work in winter, a boiler is connected to the fan coil network. When the frost is below minus 10 ... 15 degrees, the chiller stops. The control valve switches the heating medium to the water heater line with a separate pump.

How a multi-zone system works:

1. The required number of closers are simultaneously connected to the chiller and the boiler. A four-pipe scheme is used, more precisely, 2 two-pipe dead-end branches. The power of the heating equipment is determined by calculation.
2. When the first user sets up the heating, the fan coil automation opens the flow through the "hot" heat exchanger, the second radiator is inactive. At the exit we get warm air.
3. If the second user turns on the cooling, then the closer in the next room starts only the "cold" heat exchanger, and closes the "hot" one.
4. Fan coil units of the same network operate independently of each other.

Simplified connection diagram of the elements of a multi-zone SCR, four-pipe closers are used
If for some reason the valves of all the closers close, the chiller will “understand” by the return water temperature that it is necessary to stop the cold supply and stop. The boiler automation will work in the same way.

System testing

Before starting the operation of the fan coil system, a number of test activities must be carried out. This is necessary in order to check the operability of all elements of the equipment.

Crimping

First, you need to rinse all parts of the water supply pipeline with water. Further, the entire system is filled with water and the tightness of all joints of the system is checked. The next step is to create the appropriate pressure using a hydraulic pump.The system is under increased pressure for 5 minutes. This will help locate leaks that were not detected during the initial visual inspection.

Water start

After filling the water circuit with liquid, it is possible that air will remain in the system. Its removal is carried out during the operation of the equipment and takes a couple of hours. These actions are performed using a manual air bleed valve.

It is also mandatory to check the drainage of the fan coil unit. For this, a small amount of water is added to the condensate collection tank. The liquid should gradually drain out through the drain tube. If this does not happen, you need to check the slope angle of the drain.

Food

Connection to the power grid is possible only when all sections of the equipment wiring are checked

What you need to pay attention to:

1. Rotor. The uniform air distribution and the direction of rotation of the fan are checked.
2. Automatic control mechanisms.
3. Electric heater.
4. Condensate pump.

After a final check of all mechanisms, an appropriate document is drawn up, and the fan coil units can be operated.

The condensate pump must be checked before connecting the unit to the mains.

Features of installing fan coil units

Most often, such a technique is not installed one by one, but in groups, which are distributed over rooms and floors.

• Equipment with the same hydraulic resistance, mounted on the same floor, is installed according to the diagram shown in Figure 1.
• Equipment with the same hydraulic resistance, intended for installation on different floors, is mounted according to the diagram shown in Figure 2.
• Fan coil units with different hydraulic resistance, installed on the same floor, are mounted according to the diagram shown in Figure 3.
• Devices with different hydraulic resistance, installed on different floors, are mounted according to the diagram shown in Figure 4.
• The main advantage of schemes 1 and 2 is that there is no need to adjust the circuit with the working fluid. The advantage of schemes 3 and 4 can be considered a lower flow rate of the pipeline.

Differences in the installation of different types of indoor units

Duct fan coil unit is installed in the ventilation shaft
The scheme of a four-pipe fan coil is fundamentally different from a two-pipe scheme. In the first case, 2 circuits are connected, operating from air conditioning and heating systems. When switching modes, no additional measures are required, the task comes from the remote control. For a two-pipe system, all fluid must be drained before manual changeover. This method requires additional seasonal service and costing.

The method of installing indoor units is different if the devices are located:

• at different levels (floors), but have the same hydraulic resistance (HS);
• at the same level with the same HS;
• with different HS, but located at the same level;
• with different GEs at different levels.

Installation work should be carried out at the stage of construction or rough repair of the building. After the completion of the repair, the final measures are carried out - automatic adjustment of the equipment and the installation of decorative grilles on the cassette units.

Indoor units are installed in a case-based or open-frame method:

1. Cabinet models are installed equidistantly around the entire perimeter of a room or building, regardless of the location of the rooms. This applies to a cooling-only two-pipe system.
2. Open-frame models are installed mostly hidden. For open-frame units, anti-vibration mounts are provided.

Floor-standing units are considered easy to install, for which you need to install drainage with the required angle of inclination in order to avoid liquid stagnation, connect to the mains.Correctly following the instructions or focusing on the videos, you can do the work yourself.

Wall-mounted models require the help of a specialist who must:

• make the strapping correctly;
• set up control devices;
• check the pressure;
• make thermal insulation;
• lay pipes;
• make crimping;
• connect to the power supply.

For cassette models, it is necessary to provide sound insulation, vibration protection, correctly select and cut a hole in the false ceiling, then connect to the cold water supply and the heating circuit. All connections must be checked and tested before commissioning.

Shut-off valves

Three-way shut-off valve

In cooling systems, three-way and two-way shut-off valves are installed. The trim assembly 2-way valve is simpler but less reliable. It is recommended in any case to install a three-way valve. The difference is as follows:

1. When using a 2-way valve, chilled liquid continues to flow into the fan coil when it is turned off, but this is done less intensively. Cooling continues after shutdown.
2. The 3-way valve completely blocks the flow of refrigerant, therefore, when turned off, the system does not cool the room.