Too much oil

[SIGNSTU]

We are running a Sabroe 6cly (smc106)ammonia comp. with a flooded chiller. When 2 compressers are loaded we consume alot of oil. The oil pot will fill up in 2 days. Both comp. have about 6000 hrs on them. I checked the oil ring end gap 2 yrs ago on 2 pistons and they were well within spec. This has been an on going problem. Usually oil seperaters either work or they don't. Any ideas ?

[Grizzly]

We are running a Sabroe 6cly (smc106)ammonia comp. with a flooded chiller. When 2 compressers are loaded we consume alot of oil. The oil pot will fill up in 2 days. Both comp. have about 6000 hrs on them. I checked the oil ring end gap 2 yrs ago on 2 pistons and they were well within spec. This has been an on going problem. Usually oil seperaters either work or they don't. Any ideas ?

How many run hours have they done since.
It sounds to me that the comps need a Top end Overhaul.
Your actual service intervals will depend upon your operating parameters and hours ran.
What is the frequency of your adding oil to draining it?
Basically you need to eliminate any wear issue at the compressor first.
Or are you saying that the separators are malfunctioning?
Out of interest what Mark of compressor do you have?
Grizzly

[SIGNSTU]

We have run 1000 hrs since I checked the end gap of the rings. The chiller runs at about -5 degrees (F)When I pump it down it taked about 20 min before it equalizes so the valves are good. Its a mark IV

[Grizzly]

If you are sure there is no issue with the compressor?
Have you looked at the oil return from the separator.
If it is the style I am thinking of there is a Float valve at the base of the separator. Which just maybe malfunctioning. is there a solenoid control on these?
And if so is it operating?
I have to say high oil loss is usually a symptom of valve or liner wear.
The valves may well be gas tight but when running if there is excessive ring / liner wear.
Then the comps become a very efficient oil pump.
If the rings have rotated due to piston slap, allowing the ring gaps to line up? Then the problem is compounded!
Has the excessive oil consumption always been a problem from the rebuild?
Having said all this as it is a mark 4 is it a PAC you are talking about as they have a totally different oil set-up.
Good luck Grizzly

[Magoo]

Check the strainer in the solenoid block in return line from separator.

[SIGNSTU]

The strainer has been cleaned,the selenoid is working. The system is 5 yrs old and has always used more oil than I would of liked. May be the rings have shifted and the end gaps are lining up, that is something to look at.I still think the seperator is not working the way it should.
Thanks

[RANGER1]

What type of oil return is it ie float , orifice or regulating valve ?
Float is by far the best .

If sump is pressurized to much with oil return gas & oil , it will throw oil over for sure .
Does oil return line feel very hot ?

What if you close oil return is it worse or better?

Other common problem is when people put heads on without jacking unloaders down with plug .
This can bend & damage suction valves which will cause oil carry over .

Have you checked for oil foaming or liquid carryover into compressors ?

[Grizzly]

Hi Signstu.
This may seem a stupid question but what oil level do you maintain in the sump/crankcase.
Also what is the average discharge pressure you are operating at?
Grizzly

[dolce]

already you checked the strainer clean and selonoid valve is too good I think the angle hand valve need to clean and there is orifice after the selonoid valve I think it is blocked

[radhakrishnan]

hi signtsu,

as studied u r case , i have some questions to u. i.e. is it a flodded chiller with LMC (level master control)?
if yes u pls check the heater fixed on the power bellow of the expansion valve. if it is not working, the expansion valve will remains open allways and allows more liquid to enter in the cooler above it designed limit level. so when u started both compressors it will suck all the liquid above the level and it will lift up the oil from the crank case.

thank you