Principles and characteristics of fan coil system

Fan coil is one of the important types of central air-conditioning, due to the ease of installation, use of effective, less capital investment and the high popularity.

Fan coil advantage

Fan coil air conditioning system is a semi-centralized air-conditioning system in the central air conditioning system, as a terminal device system, to be located in each air-conditioned room. Central air-conditioning fan coil system with its flexible layout, easy adjustment, saving return air duct, lower operating pressures and high degree of standardization of the outstanding advantages, has been widely used in hotels, office buildings, commercial buildings, apartments, hospitals and other high-level multi-room air conditioning systems.

Fan coil system principle and characteristics - works

Fan coil units driven by the motor, by changing the input voltage regulator wind speed, so that the amount of wind turbines to meet the needs of different interior. Fans from the power control, the indoor fan coil has a great supply of hot and cold regulation. Thus, even if the power system fan air transport, but also serve to strengthen air convection and heat transfer effects.

When the refrigerant flowing in the pipe, since the temperature of the refrigerant is lower than the air temperature, surface of the pipe is easy to form condensed water in wet condition under the mediation of the coil also has the role of heat exchange and mass exchange. To make the coil sufficient to bear the entire load of air conditioning in the room, it normally takes three to four rows of tube rows.

Condensate in the bottom-mounted coil condensate drain pan, close the disc can be discharged quickly to prevent excessive condensation of water on the affected system.

Fan coil system principle and characteristics - attention problems

Fan coil units require a higher quality of the unit. Otherwise, the maintenance workload. Units require low noise, when the noise is limited, the unit sanctuary pressure head small, and thus indoor air distribution restrictions applicable to the depth less than 6M, air-conditioned room. Water disc content easy to breed bacteria, environmental pollution restrictions.

Fan coil central air conditioning system is a common type of central air-conditioning, in a small space plays an important role. Whether the effect is conditioned from an economic point of view, fan coil units are ordinary household use central air conditioning better choice.

Four-pipe fan coil

Shortcoming of four-pipe fan coil system is, ① large investment, operation and management of the pipeline due to the relatively complex ② more system design becomes more complex, larger pipeline space.

Four-pipe air conditioning means mounted air box while cold and heat pipe coils, each coil back into a total of four, so called four controls. Two water access were cold and hot water, that is, throughout the year no matter what time, cooling and heating can be switched at any time, you can achieve some of the rooms, while the heating, cooling and some rooms. So it's high standards, the cost is high. Two air-conditioning control box in just a coil, into a back pass summer cold water, hot water through the winter. Such a system makes the whole region can only heating or cooling at the same time. Compared with the four-pipe, a water system to save it, so it's relatively low standard, low cost.

 4-way cassette fan coil unit(4-pipe system)

Advantages of four-pipe system is that, ① each end device at any time freely choose the heating or cooling mode of operation, no mutual interference, air conditioning service region can independently control temperature and other parameters; ② save energy, all energy systems available by the end of the request, unlike the three control systems, as the presence of hot and cold against the problem. In a fresh air fan coil system or fan coil systems. Refrigerant and heat medium pipes in the winter and summer operation, all using the same piping system, namely winter and return hot water, the summer using the same piped chilled water ( and return), the heat source is switched in the freezing water pump and heat exchange stations, called two-pipe system. Two-pipe system can save investment costs, reduced maintenance, control the air conditioning system is a commonly used, but can not meet the needs of year-round air conditioning system.

Three controls are cold and hot water are provided two pipe system, and then return to share the same piping system.

Four-pipe is a separate hot and cold water supply pipe and a return pipe system, inlet and outlet pipe installation switching control valve, primarily for air conditioning systems used throughout the year, that at any time of cold and heat source used by the temperature control valve switch valve regulate cold, hot water. Three, four control systems due to the high investment and operating costs, usually with special needs air-conditioning systems in use.