LG ac charging problem

[kefah]

hi
i have lg ac cool only with low ambient temp connecting comp dis. to evaporater inlet by 2 capillary tube
its compressor is burned
so i replaced it with new one
but whle charging with ***** and pressure reaching 50 psi and 12 amp current and suction line start cooling suddenly the pressure reaches 90 psi and current is 25 amp
some expert advice me to remove the low temp selonid valve sensor and without result
then i removed the solonid valve and its capillary so pressure stabled at 55 psi and 25 amp
then i connect aditional one capillary tube between the filter dryer and evaporater now
so capillary tube number been 3
pressure stabled at 55 with weak ref effect
and current is 15 amp.
where is problem

[Brian_UK]

Problem is that you no longer have a purely LG unit, you have modified it and it is no longer at the design specification.

[kefah]

i didnt made a modifying to design
firstly i replaced the damaged compressor with new one with same LRA

[Brian_UK]

i didnt made a modifying to design
firstly i replaced the damaged compressor with new one with same LRA:eek:

See your first post....

some expert advice me to remove the low temp selonid valve sensor and without result
then i removed the solonid valve and its capillary so pressure stabled at 55 psi and 25 amp
then i connect aditional one capillary tube between the filter dryer and evaporater now
so capillary tube number been 3

[kefah]

sorry you didnt understand me
i mean before i made modification to capillary and solnid valve the problem is happened
since the prob occurred after replacing compressor directly

[monkey spanners]

LRA is not the correct way to match compressor duty.

[kefah]

so how to match compressor duty

[The Viking]

so how to match compressor duty

Apart from the obvious way of ordering a direct replacement from the manufacturer of the kit (LG) the only other way would be to compare motor loads and capacity graphs.

[kefah]

compare motor loads and capacity graphs
can u explain more

[The Viking]

First,
You do know that LRA stands for "Locked Rotor Amperage" i.e. this is the current the motor might pull after it seized but before the windings melt?
(Absolutely useless when selecting a compressor but vital when you size up cables and control gear feeding it)

One indication of the capacity of a compressor is it's rated horsepower but that is only an indication.

To correctly size a replacement if a direct replacement not is available you will have to look at the volume and displacement as well as performance charts/graphs/tables for the compressors.
There you will find their rated duties for varying running conditions/temperatures and refrigerants.

Have a look under [Performance Data] in THIS DOCUMENT (http://www.ra.danfoss.com/TechnicalInfo/Literature/Manuals/17/FRCC-PK-016-A2-02-MLZ-50%20hz.pdf) and you will get an idea of what I'm talking about.

:cool:

.

[kefah]

thank you man you realy helped me
so if i chose the properly compressor
then should i reweld the the patrs i removed before and return them to original places
i mean capillary . selinoid valves

[kefah]

please close the thread