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Dimitris
27-05-2008, 10:44 PM
When the pressure drop of the water is lower than normal, we usually have a low SST. When the pressure drop is extremely higher than normal, what do you think would happen?

Brian_UK
28-05-2008, 12:09 AM
If you are talking about the pressure drop across the evaporator then a higher than normal drop means that there is a blockage.

If there is a blockage then the quantity of cooled water is reduced and the chance of a frozen evaporator is increased.

Dimitris
28-05-2008, 04:16 PM
Thanks for the response, but I think I didn't make myself understood. What I meant was if the water flow was higher than normal, would there be any problems in the refrigeration circuit.

Brian_UK
29-05-2008, 12:32 AM
With a higher than design water flow you will get reduced \ extended pull down due to poor heat transfer.

nike123
29-05-2008, 06:19 PM
Thanks for the response, but I think I didn't make myself understood. What I meant was if the water flow was higher than normal, would there be any problems in the refrigeration circuit.

Check this thread:
http://www.refrigeration-engineer.com/forums/showthread.php?t=13199

wambat
29-05-2008, 07:55 PM
Flow rate must be regulated closely, because too low a flow rate reduces chiller efficiency, leading to laminar flow which results in poor heat transfer and short cycling
The minimum flow rate is typically around 3 ft. per second. However, too high a flow rate leads to vibration, noise and tube erosion. The maximum recommended flow rate is typically around 12 ft. per second.
Minimum water flow rate is 1.8 GPM per ton of heat exchanger and optimum is 2.4 GPM for a 10*F heat exchanger

Dimitris
30-05-2008, 08:33 PM
Thanks guys for the posts! I appreciate the time you took to write.