Principle of water fan coil unit: one or more sets of refrigeration main units generate 7℃ chilled water, which is sent to indoor fan coil unit. After heat exchange, the chilled water is returned to the refrigeration main unit to continue cooling, thus realizing a refrigeration cycle. The principle of indirect cooling is adopted.

Principle of fluorine air conditioner: the normal temperature refrigerant liquid from the refrigeration main engine is throttled by the expansion valve and enters the evaporator to absorb heat and evaporate, taking away the heat of indoor air to realize a refrigeration cycle. The principle of direct cooling is adopted.

Difference:
1. The water fan coil is suitable for large and medium-sized places and can realize one-to-many operation.  Freon air conditioning is suitable for small and medium-sized places, mostly one-to-one.
2. Centralized control is mostly adopted for water fan coil units.  Fluorine air conditioner adopts one-to-one monomer control;
3. The water fan coil can realize constant temperature and has high comfort;  However, the room temperature of fluorine air conditioner fluctuates greatly and its comfort is poor.
4. The cost of water air conditioner is high and that of fluorine air conditioner is low.

You can choose according to the actual situation: the size of the site, the initial investment budget, etc. to consider which air conditioner to choose.