aspera compressor fault

[COBRAKAI]

Recently went to a chiller running on r404a. Compressor trying to start then failing. Compressor pullin 16A. Windings did not add up so replaced compressor. System fired up ok ran for about 15min then back to same fault as old compressor. All electrics where changed also.

Anybody came accross this issue before or had the same fault?

[Brian_UK]

Compressor model?

Do you have any power supply problems at all?

[charlie patt]

whats comp size ... fla... sizeof cab

[Aper Willy]

Is de spanning nog goed 400 v of 230v ezv?
Is er koelwater of doorstroming in de condensor?
Kan hij zijn warmte afgeven?
Heeft de compressor nog gedraaid juist voor je er was?

[Brian_UK]

Is de spanning nog goed 400 v of 230v ezv?
Is er koelwater of doorstroming in de condensor?
Kan hij zijn warmte afgeven?
Heeft de compressor nog gedraaid juist voor je er was?
{Translation}
If the voltage is still 400 v or 230v ezv?
Is cooling water or flow into the condenser?
Can he have heat?
If the compressor is still running just before you were there?
+

[COBRAKAI]

The model was NJ9232GK. Just before the fault the back pressure droped almost into a vac I thaught chiller had reached temp but controller still asking for compressor. Then back to same fault when i retested the windings on new comp they did not add up.. Gulp.....

[charlie patt]

good translation brian and quick you would have been usefull on a set of decks we fitted with italian wiring and itialian commisioning ticket

[COBRAKAI]

Comp is a 230v running on R404a. If by flow you mean refrigerant? Compressor only to hot to touch after fault recurred. Head pressure was 250psi but I reduces this to 200 with fan speed controller. Back pressure was 30/40 psi, before fault.

[install monkey]

blocked capillary or expansion valve,causing the compressor to go out on klixxon!

[COBRAKAI]

I blew lines through with ofn before pressure test to ensure no blockages. Also monitered head pressure guage and vacced through low side for it pulling. All ok system has pressure switches installed so it would have stoped on high pressure if blocked. Back pressure did drop rapidlay thats why i thaught solanoid had de enirgized but it hadnt.

[monkey spanners]

Cut the original comp open and see what has gone wrong with it, may point you to what is wrong now.

[mikeref]

Strange to have low pressure drop and compressor stall as well. I'm thinking there is power supply problems. Sticking my neck out... solenoid looses full voltage and valve closes then low voltage drops compressor out as well.:confused:??

[nike123]

First, you should measure voltage at compressor terminals with instrument which has min/max function until error is repeated and see if MIN voltage is lower than 187V. If yes, you have power supply problem or some component in series with compressor power supply is faulty.
If not, than you should measure current and pressures and if they are matching with data given here:
http://www.embraco.com/DesktopModules/DownloadsAdmin/Arquivos/943NA01_ig.pdf

[COBRAKAI]

Thanks for tip and download document I will try that. Having a think about it today I think solenoid valve must have deenirgised due to temp in chiller. This is what has caused pressure to drop and compressor has then failed on start up.

[nike123]

Is this pump down system? Where is solenoid placed? How many pressure controls you have?

[monkey spanners]

Is it a high starting torque compressor?

[thebigcheese]

have you tried bench testing the old comp to see if it runs when not on unit.... will give u a beter idea if the comp is faulty or it is the system its on

[COBRAKAI]

The comp is a high torque comp which starts using a 90uf cap. It has a duel pressure switch low side is set for 18psi and high side was 400psi I cant rem what diff was set for. Solenoid valve has been mounted right next to evap and the run is approx 10m. I don't have the facility to bench test but was thinking of getting a comp analyzer to see if it can start comp. Has any one got experience with one are they any good?

[thebigcheese]

all you need is to wire live and neutral onto the comp electrics..... do it anywere

[COBRAKAI]

didnt think you could test the comp like this as it req a high kick start cap. I will try it and see thanks for the tip. How long could i leave it before the poss of damage or ware. Say 5 min?

[tonyelian]

hi
did you change filter drier.surely you have a restriction causes compressor failure to restart.you can check if there is a restriction when compressor pull into vac.i wonder compressor should stop you said low side is set to 18 psi.you can check your lhp & system components dirty condenser blocked drier dirty expansion valve screen.hope that help

[COBRAKAI]

hi
yes dryer was changed defo no restrictions in system. When i go back i will run a straight feed to the compressor independently from control circuit and see if it starts. Its just strange that it failed on restart comp was just clicking wanting to go. My thoughts are that windings have failed but this is very uncommon on a new comp. Plus to have the same fault as one removed. STRANGE! I'm 90% certain that power in circuit is OK I tested it but did not monitor it over a period of time.

[COBRAKAI]

Hi all
Thaught i would keep post updated. Decided to change comp as suspect windings failure. New compressor started first time and currently running away nicely. Old compressor failed after first or second restart. Will give it a couple of days and see how it goes.

[farrefriger]

by any chance were the compressor electrics
box laying flat when this happened two the frist compessor

[COBRAKAI]

Hi
No not the first compressor that we condemned but the one that was changed where.
Could that have been an issue?

[mcunliffe4]

If you suspect a compressor burn out, install a suction line drier just upstream of the compressor, allways quote the customer the cost of returning to site to remove the drier....

[thebigcheese]

if the electrics were lyin flat then theres always a chance that the relay wont change from start to run therefore going out on clixen