View Full Version : Ice formation at low side of compressor

24-12-2016, 07:36 PM
hi friends how are you all?
As i have joined new compny here R-404a, system of Bitzer comp rack system are installed for blast freezers. there is ice formation in all comps at suction side of each comps, the contractor is saying this is due to Low condensation , as here the climet is very cold so condensation is not proper. what are the possibilities? plzz suggest me i am new to ***** refrigeration system.

24-12-2016, 08:36 PM
Ice forming on the suction flanges is quite normal for low temp applications , If you were evaporating at -28c and you had 20k super heat at compressor your suction gas would still be entering compressor at -8c and ice would form . Check your super heat to reassure yourself you have no liquid and all is good . Personally id be more worried if i had no ice forming at low temp applications unless the run was very long.

24-12-2016, 08:41 PM
Ice is farming on compressor at suction side, and contractor is saying need to calibrate fan and pump differential switch, and also to replace the filters and suction line strainer.

The Viking
24-12-2016, 08:41 PM
First of all, the ice is formed because of the cold temperature of the suction gas that is "coming back" to the compressor.
Without having any knowledge about your installation, the ice forming is most likely normal and nothing to worry about. The important thing to look for is that the refrigerant returning to the compressor is superheated and that the oil isn't washed out of the compressor by liquid refrigerant.

Cold climate would aid condensation, not hinder it. Over-condensation, whereas too much refrigerant is held in the condenser, could happen during cold ambient temperatures but this, on it's own, would not cause suction side ice build up and is more likely to present itself as poor performance or a shortage of refrigerant.
Over-condensation can be prevented by proper system design, most commonly by including fan speed control for condenser fans.


26-12-2016, 11:25 AM
As you mentioned blast freezer I guess the temperature requirement in the range of -20 to -40 C . If so you would see ice formation in the low side and it is normal. Replacing filter drier or strainer is not necessary unless the sight glass turns wet. Please measure the suction pressure and compressor shell temperature that tell us either compressor is safe or not

26-12-2016, 12:54 PM
Our friends told every thing
Also be careful about ice goes to conection electric box on the compressor and might you need to put heater inside and out side of that and it should be good sealed from out side weather
This is very very important

26-12-2016, 10:45 PM
Good point mbc ,years ago when i did ice plants we used to grease over the compressor terminals to stop any water forming around them , Even though the ice rarely forms past the compressor flange you could get a nice sweat running a bit up the compressor as the line sets used to be short on them.

30-12-2016, 06:35 PM
thanku guyz for all your replies.....and sharing this kind imp knoweldge..thanks for all

30-12-2016, 08:58 PM
Have you checked the compressor suction super heat is at or above compressor manufacturers minimum level.
The purist desk jockey engineers say, the enthalpy of saturated suction vapor at correct suction super will not form hard crusted ice at suction valve.

12-02-2017, 09:19 PM
Try to close little expansion valve

13-02-2017, 03:40 PM
Don't touch the expansion valve until you have checked the suction superheat.

13-02-2017, 07:09 PM
Good pint tony told
To touch of expansion is last one
Check all option might can happen
Fans working
To much opening of door
And last one should be expansion