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mars007
07-12-2009, 11:58 PM
Whats should be the oil usage for a 58 ton arena ammonia refrigeration plant.

the compressor is a Mycom Recip. using Cimco's type C oil.
Seems its going through a lot of oil.
could also be just me. finally have something that wont break on me.

thanks in advance

NH3LVR
08-12-2009, 02:18 AM
How much is a lot of oil?

US Iceman
08-12-2009, 04:14 AM
If you take out what you put in, you are in good shape.

It's difficult to state an allowable oil carryover. Some old machines are fine, while others can pump oil like crazy.

Some oil separators do a good job, and others may have hidden issues such as elements blown out, dirty elements, or defective oil return floats.

Frank Day
08-12-2009, 04:18 AM
Hi mars007.

What may I ask is an arena compressor, is it an ice rink that you are working on?

What are your operating conditions? Saturated suction and discharge temperatures and as NH3LVR asks is how much is a lot of oil?

What kind of oil separator do you have and is your oil return system from the seaparator to the compressor functioning properly?

Regards

Frank Day

D.D.KORANNE
08-12-2009, 10:41 AM
1)use a helical type oil separator for better separation of oil .
2) instal oil separator away from the compressor for it allows cooling which helps oil separation .
3) as mentioned as much as is separated , it should return .
4) also you will need oil traps at various points for removal of oil which is carried forward through separator over and above at liquid receiver

mars007
08-12-2009, 08:05 PM
Well, im no enginneer here, im just the manager here at the rink. Ill try to answer all your questions.

I'm going through about 1/4 gallon every week. Im working with a artificial ice plant.
Suction temp/pres. is +4F/20psi
Discharge temp/pres. is 84-96F / 150 - 175 psi.
Oil Seperator is 1974 built Vilter
The compressor is a 06 rebuild Mycom N6B
the evaporator is a 07 build.

Hope that helps guys. Thanks for all the replies.

mars007
08-12-2009, 08:09 PM
I beleive the oil return is wokring since its warm. I was told if it was cold it meant it wasnt working

US Iceman
08-12-2009, 09:05 PM
Discharge temp/pres. is 84-96F / 150 - 175 psi.


150 psig = approx. 85°F saturation temperature
175 psig = 93°F saturation temperature

I see a problem...

If you are reading 84-96°F actual discharge temperatures at the compressor (not condensing temperature in the condenser) for those discharge pressures you have liquid droplets or an aerosol going through the compressor. The actual discharge temperature at the compressor should be closer to 150-200°F.

Either that, or you gave us the saturation temperatures (equivalent temperatures based on pressure).

mars007
08-12-2009, 09:40 PM
The actual discharge temperature at the compressor should be closer to 150-200°F.


i have those numbers but its psi. Maby my dial is too old here. I know that if the discharge dial doesnt get to 150 fast enough, the compressor stops on low pressure.
If it goes over 210, it stops on high pressure.
Cimco guys told me that and ways to fix if ever it happened.

US Iceman
09-12-2009, 12:36 AM
i have those numbers but its psi.


They are not just numbers. It's either pressure or temperature.

Are you reading the numbers from pressure and temperature gauges? Because the two are different.


The only thing I can think of is you are using the temperatures on the pressure gauge as they are the same as the saturation temperatures. The temperatures shown on the pressure gauge are offer only a partial picture of what is occurring. If this is what you are stating it offers misleading information on trying to offer assistance.

There should be thermometers connected to the compressor discharge lines, not just pressure gauges.

If you are only getting 1 quart a week out of the system, how much are you putting in?

The more I think about this the more I think you are worried about nothing.