First, fan coil introduction and characteristics:

Fan coil is the ideal end product of central air conditioning, fan coil is widely used in hotels, office buildings, hospitals, commercial and residential, scientific research institutions and other places. The working principle is that the fan sends indoor air or outdoor mixed air into the room after cooling or heating through the surface cooler, so that the indoor temperature is reduced or increased to meet people's comfort requirements.

Main advantages:

Small size; High efficiency; Low noise; Low energy consumption. The body structure is exquisite, compact, strong and durable, the coil is made of high quality galvanized sheet shell, the condensate pan is formed by molding process, no weld, solder joint, and the insulation material in line with the fire protection standard is connected to the water pan.

Main disadvantages:

Because this method is only based on convective heat transfer, which causes the indoor to reach the best level of comfort, it is only suitable for places where people stay for a short time, such as offices and hotels, and not for ordinary homes. Due to the increase of the fan, the cost and operating costs are increased, and the maintenance and management of the equipment are also more complicated

Second, working principle and common style:

Relying on the forced action of the fan, the air passes through the coil, and the air in the room is continuously recirculated in the unit, so that the air is cooled (heated) after passing through the cold water (hot water) coil to keep the room temperature constant.

Common styles:

Horizontal concealed (with bellows) fan coil;

Horizontal open-mounted fan coil;

Vertical concealed fan coil;

Vertical open-mounted fan coil;

Cassette type two-outlet fan coil;

Cassette type four-outlet fan coil;

Wall mounted fan coil;

Vertical cabinet fan coil.

By form:

There are five kinds of horizontal concealed installation, horizontal open installation, vertical concealed installation, vertical open installation and card type.

By thickness:

Ultra-thin type, ordinary type.

According to whether condensate pump:

Ordinary type, luxury type.

Static pressure by unit:

0Pa, 12Pa, 30Pa, 50Pa, 80Pa (external static pressure).

According to the number of rows:

Two rows of tubes, three rows of tubes.

According to the standard:

Two controls, four controls.

Two rows of tubes, three rows of tubes:

Two rows: that is, two rows of copper pipes, each row of 8, a total of 16 copper pipes.

Three rows: three rows of copper pipes, each row of 8, a total of 24 copper pipes.

The several rows of fan coil refers to the number of rows of copper tubes of the fan coil cooler, and the more roots of the copper tube, the better the cooling effect.

Two controls, four controls:

Two controls: ordinary fan coil cooling in summer, hot water heating in winter

Four controls: used in some more luxurious places, you can walk hot and cold water at the same time, that is, you can cool some rooms and warm some rooms according to your needs

Control mode:

Simple control: Use the three-speed switch to manually control the three-speed conversion and start and stop of the fan directly

Temperature control: The thermostat automatically controls the opening and closing of STV series electric two/three way valves according to the comparison and calculation between the set temperature and the actual test temperature; Directly control the three-speed conversion and start and stop of the fan, so as to achieve the purpose of constant temperature by controlling the water flow or air volume of the system

Third, the impact of parameter changes on performance:

First, the fan coil air volume is certain, the water supply temperature is certain, when the water supply changes, the cooling capacity changes with the water supply, [source: refrigeration encyclopedia public number], according to some fan coil product performance statistics, when the water supply temperature is 7 ° C, the water supply is reduced to 80%, the cooling capacity is about 92% of the original, It shows that the cooling capacity is affected slowly when the water supply changes.

Second, the fan coil supply and return water temperature difference is certain, when the water supply temperature rises, the cooling capacity decreases, according to statistics, when the water supply temperature rises 1℃, the cooling capacity is reduced by about 10%, the higher the water supply temperature, the greater the reduction, the dehumidification capacity decreases.

Third, the water supply conditions are certain, when the fan coil air volume changes, the cooling capacity and air treatment enthalpy difference change with the general cooling capacity is reduced, the enthalpy difference increases, and the fan power consumption per unit cooling capacity does not change much.

Fourth, when the temperature difference between the inlet and outlet of the fan coil increases, the water volume decreases, and the heat transfer coefficient of the heat exchange coil decreases. In addition, the heat transfer temperature difference has also changed, therefore, the cooling capacity of the fan coil decreases with the increase of the temperature difference between the supply and return water, according to statistics, when the water supply temperature is 7 ° C, the temperature difference between the supply and return water is increased from 5 ° C to 7 ° C, the cooling capacity can be reduced by about 17%.