Horizontal surface mounted fan coil unit mainly by the fan, heat exchanger (coil), condensate water, housing and controller, and it applies to centralized air conditioning system. Advanced design, full range, superior performance, versatility, usually used to require low noise, temperature regulation and flexible variety of hotels, apartments, restaurants, hospitals, commercial buildings and so on. Choice points: a main control unit selection parameters rated air flow, export static pressure, input power, rated cooling capacity, rated for heat, noise, water resistance and so on. 2. The fan coil unit air about 250 ~ 2500m / h, exit static pressure is less than 100Pa (exit static pressure greater than 30Pa for high static pressure type). 3. The selection of the unit should be room specifications cold, heat and air heat and moisture loads than other factors to determine: 1) if the fresh air and room air enthalpy parameters, fan coil units only burden the cold room envelope and internally generated, heat load; 2) When a new air enthalpy value is greater than or less than the room air enthalpy, fan coil units should be added or deducted part of the new air-cooled heat load; 3) when the absolute moisture content of the fresh air is below room air moisture amount, when the full burden of the room can be wet load, fan coil units affordable room only sensible heat load, should be configured according to the dry conditions; 4) When the room account for a large proportion of the sensible heat load, should adopt sensible heat balance calculations, checking fan wind coil unit. 4. In the selection of the unit, you should consider the actual performance and ratings of bias, and note the following characteristics: 1) unit rated cooling capacity is generally equal to the value of air enthalpy drop 15.9kJ / kg under the conditions of the test value; 2) Single coil units rated for heat is generally 1.5 times the rated cooling capacity; and 3) the rating values ??of the parameters are the fan speed at the high-end, the design wind speed generally advised by numerical midrange product samples under selection. If the product does not provide ratings data under different wind speeds, can refer to Table 3 for conversion. Table 3 wind wind speed conversion coefficient rating category upscale mid-low speed wind speed wind 1 0.75 0.50 6. For dual control water system (applicable only on a seasonal basis or only by air-conditioned area air conditioning system heating or cooling converted) fan coil units, configure only one set of coils, winter heating / cooling dual-purpose models. For the four control water system (for heating / cooling air conditioning system frequently conversion) of fan coil units, heating and cooling should configure two coils combined models. 7. The low temperature storage air conditioning system should be used in a large temperature difference unit. 8. Currently, fan coil units have the following control types: 1) with a three-speed selection switch, winter, summer transition temperature controller linked via waterways electric valves, implement automatic control; 2) with a three-speed selection switch, winter and summer transition temperature controller linked via fan-OFF, implement semi-automatic control; 3) with only a three-speed selector switch, the implementation of manual control. 4) variable speed fan control. According to the energy efficiency standards should be used in combination electric thermostatic valve and third gear speed control mode. 9. selected products, should pay attention to the noise, condensation and equipped with a motor quality three questions. It is currently sampling, quality problems more projects. 10. The fan coil units abroad labeling method is different, and the difference between the design selection should pay attention to.