Why the saturated suction temp of liquid chiller R-123 is higheir than leaving water,what is the cause??

Question

Why the saturated suction temp of liquid chiller R-123 is higheir than leaving water,what is the cause??

Answer 1

because there's limitation in heat transfer between two fluids. There's a minimum temperature difference between the hot fluid and cold fluid in order to make the heat move across the two fluid. Because that temperature difference is the driving force for heat transfer. The minimum temperature difference is usually around 5-10 degree C.

Answer 2

If the refrigerant is indeed cooling the liquid, it has to be colder than the liquid. Therefore, I believe you may have a defective temperature sensing element.

Are you measuring the suction temperature at the chiller barrel or elsewhere else ? If elsewhere there may be some warming as would occur through an economizer heat exchanger.