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question mark
24-04-2013, 12:48 PM
hi guys
why do we get ice on suction line near the compressor after the insulation bit, when we know that both condenser fan and evaporater fan are working properly and we know that the system is short of gas. TX valve system with receiver. bottle cabinet.
thanks

Sandro Baptista
24-04-2013, 02:11 PM
Maybe is working with low evaporating temperatures -30ºC....-35ºC and with low condensing pressure. The discharge temperature would not be high enough so the ice disappear (with R404A /R507 the discharge temperatures are lower than with R22).
No problem with that if no liquid goes to the compressor.

nh3simman
25-04-2013, 09:59 AM
Why is there ice on the pipe?
1. If the surface of the tube is below the dew point of the surrounding air, you will get condensate.
2. If the surface is below zero, the condensate will freeze.

Why on the suction line near the compressor?
Because this is the lowest temperature in the cycle.

Why is gas charge significant?
Low charge means less liquid in the condenser.
This means more condenser heat transfer are available and therefore lower condensing pressure.
This leads to lower suction temperature (given a fixed pressure drop in the expansion device).

Rob White
25-04-2013, 12:46 PM
.

As stated above.

Ice only means the pipe is cold.

If the system is a freezer and the room is at -20 degC
then you will easily have ice on the suction pipe.

Rob

.

sokold
25-04-2013, 04:34 PM
I'm assuming a bottle cabinets' set point is going to be above zero and as such, the evaporating temp is going to be -5*C ish. If the system's short of gas then the super heat will be fairly high and certainly not cold enough to form ice. Sounds like the coils iced up to me.....going on the details provided by the op. Unless it's a bottle freezer of course (can't say I've come across many of those!) Need more info really.