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View Full Version : Need some idea on cascade system



joweibee
27-04-2012, 03:36 AM
Hi Guys,

Newbie here.
We have this environmental chambers wherein we use a cascade system using R404A for the high stage and R508B for the low stage, when is use this chamber for medium temperature only e.g 0*C wherein it will only use the High stage compressor, it does run well and reach the setpoint but when i use it for low temp like -40C where it needs the R508B compressor, the temperature goes up instead of going down. the standby pressure of R508B is within its specification but when i run it, the suction pressure goes to 0 Psi.

any idea from you guys?

thank you in advance..

Emmett
27-04-2012, 12:28 PM
1. How are you checking the stactic charge?
If your static charge is correct and you are absolutely sure of this then you have to have a restriction in your liquid line, either a solenoid failing to open or a plugged filter drier. If you can upload a mechanical print and a electricl print. I am sure we can help you diagnose this problem.