What causes for a scroll compressor to fail?

hello guys im a newbie here at this forum. ive got one question for all of you hope you could help me... We installed 10 TR scroll Compressors on our ACCU and they are failing one by one. The brand is maneurop but made in China. We already reprocess the system and were sure that it is already clean. What's the causes for this Compressors to go high ampere? is it the Bearings of these Compressors weak? voltage fluctuation? These Compressors is 380v/3ph/60hz. The number of compressors that went down is 12 compressors already... And the manufacturer of these Compressors dont want to warrant their units because they said the problem is not on their compressors. They blame it on the electricals and they said the system is not clean. :confused:

have you checked the contactors, have you got one pole down which is causing the motor to two phase, this will give you the same symptom as a ceased comp

Hi ArticboyCould be many things with 12 failures it would be worth spending some money on testing. One, test of an oil sample can indicate most refrigerant faults. Two, install a data logger to a unit V + I, and another to the common supply for all units, test the power circuit with an electrician. I'm sure the data logger for a week or two will pick up 95% of electrical faults. Innitially check the basics first like use an IR thermometer on elect terminations, contactors, motor. Failling bearings, acid, moisture, air, will show up in the oil test. Its cheaper to hire data loggers. May the force be with you

will it be the problem of oil return, rotation direction

hi...you said high amps, either excessive refrigerant or low voltage......on start up of a new compressor are you getting high amps?

Are there any 3Ph protection devices installed,i.e upon incorrect rotation the protection devices would instantly cut out the signal to the compressor.

Regards
Jase

Just a thought but do you have any crankcase heaters and do they actually work, because in my dealings in the past if there is any liquid in the sump then say bye to your compressor!?:eek:

go for oil return me thinks,have the failed units got enough oil still in them? is the oil return system working or is it a bad design,i would sit there and watch it load up and down and see if any of the comps are being starved of oil and others getting flooded, and are theese compressors the right operating temperature for the application,:eek:

Hi, flooded liquid in the suction line or lackage of oil will result in high amps, check the recharging amount in your system. Otherwise, the higher discharge gas temperature will destory the scrolls.

I would have the compressor stripped by Preston refrigeration, they will do a report and tell you the most likely cause for the failure.
is it burnt out, ie windings overheated and blackened, is it due to moisture, Ie there will be a gold / copper sheen on the inside casing where it should be steel. Has it hydrolocked with oil, ie the compressor will be over full of oil (this happened on the old lindie booster packs, took out loads of manuerops before they suzed and corrected the problem.
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I would investegate the compressor very thoughaly before looking deeper at the system, that should give you a good direction.

Hi,
i think you better check the power supply,your voltage in phils is 440 3 ph right, in you compressor you must use 10% + -.i hope im right.

seeya

there is one thing for sure its system failure thats causing your compressors to fail i find it hard to believe you have lost twelve compressors

The samples of the oil from the compressor is dark which is a sign of burnout. The the compressor was brought back to the manufacturer for them to study and analyze. Thanks for the replies.

The system is not flooded. We dont install crank case heater because we are in a tropical country.\The compressor has an internal overheating protection and single phasing protection. The oil that we got from the sytem is dark which is a sign of a burnout. We send the damage compressor to the manufacturer for further study.

Have you done an acid test??

acid test? not yet sir

Personaly after the third dead compressor I'd be doing a full out audit of the system checking every thing right down to the type of silphoss being used!

Check - Electrical supply and control and all other sub systems such as sensors and remote controls.
Check - Safety cut outs for opperation (LP, HP, Oil cut outs)
Check - Oil for Acidity and quality, Moisture, Contaminants
Check - Condencers and fans and all related sub systems
Check - Evap and all related sub systems

Once up and running with all other facets checked during the off phase, and no load checking of the electrical and the system is charged run a full set of electrical checks again with it running and then maticulusly check sub cooling, super heat & take oil samples every second day for analisys for one week.

Doing that is allot cheaper then buying compressors by the crait!

most probably lack of oil returning to the motor.
is your outdoor (ACCU) was higher than your indoor (AHU)? check your oil traps, filters.

You need to do an inspection and do the following:
Take the suction and discharge pressures; Amount of superheat at the compressor inlet; Return gas temperature; Discharge gas temperature; Amperage; and Applied voltage to the compressor.
These are the signs and symptoms of the five main causes of compressor failures:
1. Refrigerant floodback;
2. Flooded starts;
3. Slugging;
4. Overheating; and
5. Loss of oil.
More times then not, the compressor is not the problem, it's usually a system problem.
My suggestion to you is when you are asking for advice, you always do and give as much of information as the above. Asking a general question is not enough information for most of us to give you a good answer

The systems oil are ok, and the system is ok also. The engineers of the of maneurop alredy visit the the and watch us reprocess the system. and they are the one who start up the unit. maybe the compressor is really weak. because it is made from china and this model 380volts are the first batch that comes out from the factory.

hi, the suggestions from other respondents are helpful - the debate is whether it's system issue or power supply problem. Respectfully and knowing some of the anecdotal history of Philippines with regards to power generation from Marcos' time, i.e shortages "brownouts" , voltage surges and dips are still a feature of life. Not taking the side of Maneurop but I would suspect the power supply. Do the tests and data logging as the other colleagues suggested. Next time, you should " plug" a couple of units into a stable genset and compare running with grid powered units over some weeks. In this type of dispute this is a useful reference test, all other things being equal, it will confirm power is issue or not. I know of this being done before. It should not get to 12 failures before someone called an investigation. Good luck with tests and keep us all posted!

Can you describe the application details and initial startup procedures and cleaning procedures, if possible what are the system safety devices.

Best regards,
ravi perumal