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Mish
25-07-2008, 07:27 PM
Can anyone explain some reasons for my system tripping on LP. Its an industrial system in a food processing factory. Running with a Caryle compressor, 63amp. Also some typical reasons for high/low suction pressure and high/low discharge pressure.
Cheers

GXMPLX
25-07-2008, 07:48 PM
It means your compressor is pumping more refrigerant than what's being injected into the evaporator.
This may be caused normally by reaching temperature and has pump-down installed.

This may be caused abnormally by:

Expansion device not feeding enough refrigerant.
Not enough thermal load in the evaporator.
Not enough refrigerant in the system.
High pressure drop in the suction line


High discharge pressure is not the same as high condensing and would be mainly caused by high pressure drop between the condenser and the compressor.

Depends on where you are measuring it could even be caused by having the discharge valve partially closed.

ART KUHN
25-07-2008, 10:01 PM
5 frozen evaparator

cheers

monkey spanners
25-07-2008, 11:06 PM
Lp switch out of adjustment or faulty.
Blocked suction filters or strainers.

chemi-cool
26-07-2008, 09:07 AM
LP will trip only if the pressure is below the set point + differential.


The reasons can vary,

At this point your skills as a fridgy are tested,

Good luck.

Peter_1
26-07-2008, 09:46 AM
At this point your skills as a fridgy are tested,


Good one Chemi :o

GXMPLX
26-07-2008, 01:46 PM
LP will trip only if the pressure is below the set point + differential.


The reasons can vary,

At this point your skills as a fridgy are tested,

Good luck.

Not with the ones I work with! Correct setting would be just cut out. Cut in is Cut out - differential

GXMPLX
26-07-2008, 01:47 PM
Lp switch out of adjustment or faulty.
...

Good point! I have to remember this but havent't had a faulty one in some time!