The unit is a central air conditioner suitable for various industrial and commercial places such as hotels, shopping malls, office buildings, factories, etc., and can introduce fresh air to improve indoor air quality, air conditioning, air ducts can be completely concealed, and can also be independently controlled and operated in zones. Simple and flexible. Its functional methods include heat pump type and single cooling type. The equipment has auxiliary electric heating function, new wind function, purification type function is optional.