Chilled Water Systems
Chilled water system equations - evaporator and condenser flow rates.
In a chilled water system the water is cooled down to 40 - 45oF (4 - 7oC) by an centralized evaporator, distributed throughout the building in pipes and connected locally to air condition cooling units wherever needed.
Total Heat Removed
The total heat removed by an air condition chilled-water system can be calculated
h = 500 q dt (1)
where
h = total heat removed (Btu/h)
q = water flow rate (gal/min)
dt = temperature difference (oF)
Evaporator Flow Rate
The evaporator water flow rate can be calculated
qe = htons 24 / dt (2)
where
qe = evaporator water flow rate (gal/min)
htons = air condition cooling load (tons)
Condenser Flow Rate
The condenser water flow rate:
qc = htons 30 / dt (3)
where
qc = condenser water flow rate (gal/min)
htons = air condition cooling load, chiller tonnage (tons)