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View Full Version : no reciever no solenoid valve chilling system



Yuri B.
10-06-2009, 09:33 PM
Not being a refrigeration engineer by the trade and the training, I need a bit of help from the professionals.

What is the point of not using on such a chilling unit of neither receivers nor - what is more important - the liquid line solenoid valves:
- two screw compressors (two separate R404a systems),
- their air-to-air condensers are at roof,
- their evaporators (beneath the compressors) are inside a common shell, chilling glycol ethylene water down to minus 8 C,
- expansion devices are EEVs.

Brian_UK
10-06-2009, 10:48 PM
Not quite sure what your question is but...

The EEV should be able to shut when no duty is required so a solenoid valve is not required.

Yuri B.
11-06-2009, 07:18 AM
The function of the line solenoid valve is prevention of liquid entering evap during compressor off times.
They are a must, so far as I know, on the freezing systems. But I am unable to discern difference between some CHILLING systems equipped with sol valve and the others without.

Yuri B.
12-06-2009, 04:23 PM
There are, nonetheless, EEV chillers both with solenoids and without - I forgot to add the last time.

Peter_1
13-06-2009, 07:31 AM
an EEV can act as a SV.
Why no receiver? Chiller manufacturers say you have to use the condenser at partial load. At partial load, you don't need that much condenser area, so you have spare condenser area to store and subcool liquid.
All these machines are critical charged.

Bones74
15-06-2009, 03:21 PM
Chillers never shut off usually. They do not have a sol and receiver because they have bypass valves. This lets the system add refrigerant to the coil to maintain temp. They are critically charged and the hot gas valve and liquid injection valve is why this style is missing what you are use to.