Oil Loss on York YK chiller

[Taicool]

It won't shutdown, the oil level will slowly drop down to around 1/5 sight glass, then maintain in that level, the operator told me he stopped the chiller on 5:00 PM in the afternoon, and found the oil returns sump with full sight glass next morning.

on Jan this year when I was there I replaced dehydrator on the oil return line because I found the temperature of the tube back to oil sump(it is a YK style G chiller) was not so cold as there wasn't much dew gathered, it seemed helpful for the oil return and the oil sump level raised to 1/3 in three days,
just two weeks ago the operator called and said the problem came back again, he also replaced a dehydrator, but this time it didn't work, the return line was warm, oil level keeps dropping, so they had that chiller stands by for repairing.

[KnewYork]

just two weeks ago the operator called and said the problem came back again, he also replaced a dehydrator, but this time it didn't work, the return line was warm, oil level keeps dropping, so they had that chiller stands by for repairing.

Then this sounds like you have an oil eductor problem. That could be caused by a couple of different things. I wouldn't be too hasty in making it a compressor problem. One of the possibilities is a failed solenoid valve or coil on the oil eductor line. I've seen that before.

[Abugarcia]

taicool, what did you find the problem to be, or did you fix the machine?

[Random1634]

This is a few months old I'm guessing he isn't coming back to post his findings. If the line in the back of the sump is warm like he is saying either your eductor is clogged (which I doubt), or his refrigerant level isn't right in the evap. Easiest way is to check your approach on the evaluation, assuming you have a two pass with clean tubes and proper flow it should be less than three degrees. I'm not quick to say low charge with that garbage variable orifice but if your approach is high I'd drop the condenser level 5% or so and see if it starts working again. Just be sure to watch your discharge superheat when doing this also. You don't want it to get below 15 at full load.

Sent from my SPH-L900 using Tapatalk 2

[kenlmc]

Oil can not come back to the sump after chiller shutdown if it is mixed in the refrigerant. This should eliminate any oil eductor or return problem. It sounds like the built in emergency oil reservoir housing is completely filling up with oil instead of being filled with part vapor...

[Nuclrchiller]

Welcome to the site Kenlmc. You may want to check the dates of threads before you post. Just sayin'...

[kenlmc]

It would be nice to have closure... The guy should have came back and told what actually fixed the problem.

[KnewYork]

Oil can not come back to the sump after chiller shutdown if it is mixed in the refrigerant. This should eliminate any oil eductor or return problem. It sounds like the built in emergency oil reservoir housing is completely filling up with oil instead of being filled with part vapor...

Please explain how the emergency reservoir could have vapor in it when oil pressure nets at about 30 PSIG.

[DITAW]

Please explain how the emergency reservoir could have vapor in it when oil pressure nets at about 30 PSIG.

This should be interesting

[irvedwmac]

Hi Guys,

We have a York centrifugal chiller (YT-B1 B1 B2 C07) which seems to be having a problem with the oil seal between the impeller and the motor.

They seem to be going bad all the time. It keeps leaking oil there all the time. We've been having to replace the seal every year.

The machine has never been torn down or rebuilt and it is 30 years old.

I've been trying to find where to post a new tread, but I don't see where yet, so I just replied to this thread.

[ehsx]

Haven’t worked for york for a good while so may misspeak….

Manual list seal as carbon on cast. Check old seal for any cu plating indicating acid conditions, the plating will kill carbon seals.

Never touch either seal surface with bare hands, inspect for any prints, rust, marks or scratches. I would inspect and clean the seals in a plastic pan with a lens tissue and degreaser. Straight from there to a plastic pan of mineral ref oil until installed. At one time I rejected 20-30% of the seals received.

Clean and make sure machined surfaces clean & flat.

Does the motor have bearings on both ends or just one. D- still requires alignment. Coupling runout must be checked.

Verify seal oil pressure.

If installed correctly most all leakage will vaporize and drip rate will be far below listed acceptable rate.

Some mfgs have gone to tungsten or silicon carbide seals due to cu plating. Extreme issues with r22 & poe lead to material changes. Carbon would fragment, harder material would peal & burp the plating.

Common seal failures:
Misalignment of shafts
Coupling spacing
Seal not installed square in hsg
Improper seal tension
Damaged or mis handled parts
Incorrect oil pressure
Acid conditions
Cold oil starts, ref mix
Bad bearings

[jayguy]

How much are you leaking and in what time frame?

[irvedwmac]

Hello jayguy,

I don't know how much it is leaking.

I know it is severe enough that they have been replacing the seal on an annual basis.

[ehsx]

Hello jayguy,

I don't know how much it is leaking.

I know it is severe enough that they have been replacing the seal on an annual basis.

York used to use a max recommendation of 5 drops per minute, Dunham Bush 7 (may have backwards). None apparent if done correctly.

[irvedwmac]

Hello ehsx,

The guys tell me that this motor has bearings at both ends. (I'm actually just the DDC programmer, who gets to write about this, because I am on the computer all day long anyway...)

My boss tells me that he hasn't gotten to see the seal surfaces, because another contractor from Johnson Controls / York takes care of that annual PM. He says that the customer practically never has a stop inspection.

He tells me that all of these things with the vibration test, motor bearings, and oil sample, that Chevy mentioned will be recommended to the customer's chief maintenance man shortly.

[darren1688]

It won't shutdown, the oil level will slowly drop down to around 1/5 sight glass, then maintain in that level, the operator told me he stopped the chiller on 5:00 PM in the afternoon, and found the oil returns sump with full sight glass next morning.

on Jan this year when I was there I replaced dehydrator on the oil return line because I found the temperature of the tube back to oil sump(it is a YK style G chiller) was not so cold as there wasn't much dew gathered, it seemed helpful for the oil return and the oil sump level raised to 1/3 in three days,
just two weeks ago the operator called and said the problem came back again, he also replaced a dehydrator, but this time it didn't work, the return line was warm, oil level keeps dropping, so they had that chiller stands by for repairing.

======

please advice how could you solve this problems ? oil loss in ch Yk, I get this problem too, already change the filter drier, and still not working, oil loss again

[darren1688]

Dear Sirs,
I have a York centrifugal chiller in VN that has oil loss problem,
Because currently I won’t be available to reach the jobsite to check the condition myself, so I made the operator to mail me the running record as attached,
The chiller’s model is YKQVQCK35DFGS,
Compressor model YDTL-95DD,
What has happened to this chiller is the oil level in reservoir will keep dropping down to the bottom of sight glass when chiller runs,
and it could take one day long for the oil to slowly return to reservoir when chiller shutdowns,
The operator has replaced the dehydrator, but it seems not the remedy,
From the record, the LOP which represent the pressure in reservoir is 37.1 Psig,
And the Evaporator P is 35.3 Psig, the LOP is 1.8 Psig higher than Evap P, based on this differential, I won’t connect the possible leak on B.P seal to this oil loss problem,
the disappeared oil is not carried to evaporator otherwise it won't recover to reservoir when chiller shutdows, then where has it gone? accumulated in the compressor?
what could the real cause for this faulty condition?
can anybody kindly advise?
Any suggestions will be appreciated.

====

please advice is there any problem with oil cooler ? I get this problem in chiller York YK, loss of oil while running, the oil migrated to evap and condenser , so the chiller safety shutdown loss of oil

[darren1688]

Dear Sirs,
I have a York centrifugal chiller in VN that has oil loss problem,
Because currently I won’t be available to reach the jobsite to check the condition myself, so I made the operator to mail me the running record as attached,
The chiller’s model is YKQVQCK35DFGS,
Compressor model YDTL-95DD,
What has happened to this chiller is the oil level in reservoir will keep dropping down to the bottom of sight glass when chiller runs,
and it could take one day long for the oil to slowly return to reservoir when chiller shutdowns,
The operator has replaced the dehydrator, but it seems not the remedy,
From the record, the LOP which represent the pressure in reservoir is 37.1 Psig,
And the Evaporator P is 35.3 Psig, the LOP is 1.8 Psig higher than Evap P, based on this differential, I won’t connect the possible leak on B.P seal to this oil loss problem,
the disappeared oil is not carried to evaporator otherwise it won't recover to reservoir when chiller shutdows, then where has it gone? accumulated in the compressor?
what could the real cause for this faulty condition?
can anybody kindly advise?
Any suggestions will be appreciated.

please advice, is there possible any problem with oil cooler heat exchanger ? I get this problem also in my chiller York YK