Central air conditioning principles include: a central air-conditioning refrigeration principle: compression, absorption, etc., this is no longer dwell; Second, central air-conditioning system works: the wind system works, water works system, coil system works, etc. , briefly as follows:
1, central air conditioning system working principle of the new wind:
Fresh outdoor air by the wind into the wind cabinet attract processor, and after the filter from the duct into the cooling and dehumidification in each room, when the wind does not meet the new indoor heat and moisture load, can only meet the required fresh air indoors With the indoor fan coil handling indoor air heat and moisture load at the same time, the excess out of the air through the valve back to the fan according to the ratio of open portion exhausted to the outside part of the return to the air inlet for reuse recycling.
    1. Vacuum valve: absolute pressure <0.1MPa namely 760mm of mercury valves, pressure is usually expressed in mm Hg or mm water column. (Steel, stainless steel, etc.)
    2. Low pressure valve: nominal PN≤1.6MPa valves (including PN≤1.6MPa steel valve) (cast iron, stainless steel, etc.)
    3. Medium pressure valve: Nominal PN2.5-6.4MPa valve. (Steel, stainless steel, mostly)
    4. Pressure valve: Nominal PN10.0-80.0MPa valve. (Chromium-molybdenum steel, cast steel, high-temperature acid-resistant steel)
    5. Ultrahigh-pressure valve: nominal PN≥100.0MPa valve. (Chromium-molybdenum steel, cast steel)