PDA

View Full Version : Oil Seperator







Samarjit Sen
04-08-2006, 02:20 AM
Dear Freinds. I would like to know the various advantages in using Oil Seperators for a Low Temperature System using R 22 and R 404A. The other day I was going through the Application Engineering Publications of Copeland, where I could locate some information on Oil seperators. Unfortunately I could download the same. Could you please also intimate the number of the Copeland Application Brochure no. so that I may trace it back.

old gas bottle
04-08-2006, 08:25 AM
firstly try and avoid using R22 on low temp applications,not so long ago there was not much of a choice when R502 dissapeared,its troublesome for various reasons,as far as the oil sep goes ,you dont want exesive quantities of oil in the evap at low temps as it will not return to the compressor quick enough and starve it,also oil can block the expansion valve aswell as cause icing up etc, oil in a low temp application tends to circulate slower arround the system so by fitting a oil sep it helps by retaining the oil where it should be and also by acting as a storage vessel for extra oil capacity, there are other reasons but hope that helps.

S.M.Gokhale
04-08-2006, 09:17 AM
Attached is a copeland service tip on Oil Separators.
You can also log on to http://www.henrytech.co.uk for more information on oil separators and capacities. Henry Technologies has recently appointed ddistributors in India. In Mumbai M/s C.P.Vaswani is the dealer. You can find dealer in your city by e-mailing henry U.K.

US Iceman
05-08-2006, 12:22 AM
I would like to know the various advantages in using Oil Separators for a Low Temperature System using R 22 and R 404A.


If this is for a reciprocating compressor, you want to use an oil separator to reduce the amount of oil getting into the low temperature evaporator.

The less oil you have in the evaporator reduces the oil return problems during normal operation. My opinion is this makes the suction line design velocity less critical. The suction line velocity is the only way to return the oil back to the compressor.

The use of the oil separator essentially helps to make the system a little easier.

If you are using a screw compressor on any temperature, you most likely will have an oil separator since these compressors are oil injected.

TXiceman
10-10-2006, 03:02 AM
I agree with US Iceman here but would like to add that I am not fond of the 400 series refrigerants due to the mixture and temperatue glides. I'd try to use R-507 and avoid both problems.

Ken

US Iceman
10-10-2006, 03:13 AM
I'm not sure what the fascination is with the 400 series refrigerants? I would not recommend them either.

From what I know about them, it's too similar to having to deal with non-condensables, so why make it more difficult to work on systems?

winfred.dela
12-10-2006, 12:23 AM
Dear Freinds.
I would like to know the various advantages in using Oil Seperators for a Low Temperature System using R 22 and R 404A.

Hi Samarjit,

(1) In R-22/R404A refrigeration system with recip compressors, you may not need an oil separator if you have a good design. Oil should eventually return to the compressor crankcase. Using an oil separator helps us feel safe with our design.

(2) Please avoid using R-22 for low temp application due to possible oil problem.

(3) Also, please avoid using R 404A due to its glide.

(4) I suggest R507 (glide=0) for low temp application, I have not incurred any problem even up to -55C tevap.

Regards
Winfredy

TXiceman
13-10-2006, 01:28 AM
Hi Samarjit,

(1) In R-22/R404A refrigeration system with recip compressors, you may not need an oil separator if you have a good design. Oil should eventually return to the compressor crankcase. Using an oil separator helps us feel safe with our design.



Basically I look at a system without an oil separator as a cheaper design. Oil belongs in the compressor and every effort should be made to keep it there. Even with good oil return, the oil will have a negative effect on capacity.

I would rather install an oil separator.

Ken

dkemper
06-04-2007, 01:11 AM
I've seen units without a separator saturate the filter/drier with oil and have high head pressure/temp issues leading to premature compressor failures.

I've seen units without a separator loose all their oil into the evaporator and not pull it back leading to premature compressor failures. (yes, my predecessor like to bypass oil safeties rather than ID and resolve oil related problems)

I've seen 24X7 units with separators have a 5 year old filter drier look new, clean and dry when changed.

I'm sold on them for low temp units.

Dan
06-04-2007, 03:58 AM
A coalescent separator such as the series available from Temprite works excellently. We have a major chain using alkyl-benzne oil with R507 and parallel rooftop applications with no problems, even though this is a no-no when you talk to the refrigerant and compressor manufacturers.

lana
06-04-2007, 08:50 AM
Hi everybody,

I would like to give some ideas.

Working with Zeotropic blends (400series) is not that difficult. Of course if one knows what he/she is doing.
There are two issues with these refrigerants and I know all of you are aware.
1- The synthetic oil.
2- The Glide.

If these two are dealt with according to standards then there must be no problems.

Secondly, about the oil separators. If the piping and traps are not designed well, then using oil separator would not help or solve the problem.
I used R22 in a double-stage recip. with oil separator. This system had very complicated piping route. BUT I didn't had a single problem with oil return (touch wood :D ). The piping also was done very carefully.
I have seen systems with oil separators which failed to return oil to the compressor :eek: .

A trouble free system comes with good design and perfect installation.

Cheers:)