end compressor runs hot dicharge temp

[zero1234]

on this same rack the end compressor runs a hot discharge temp of over 225.0 F if I let it. I have the computer shut it down at 224. for I know poe oil starts to break down at 225. Now I have the injection subcooling but this does not seem to help. I have plent of refigerant,only this compressor is running hot. I have adequete return oil. My suction press is 16 psi with 404 and my average dicharge is aroud 215.. Agin thre rest of the rack runs cool. thouh this rack has many other issues and has been worked on by three othe rcompanies over the past. none of them can tell us why we have all these failures and issues. . I also have over ten years in the indusrty,though this rack has issues

[Dowadudda]

What was rack manifold superheat?

What sort of head were you at?

Lead pump? Least hp pump?

There are many things that can cause this. You need to spell out more of the story.

[NormChris]

In addition, measure the suction line temperature six inches or so before the suction service valve. So this when you experience normal discharge temperature and again when you experience high discharge temperature. Let us know what you measure.

Also, give us the make and model of the compressor. And, the information that Dow asked you for.

Is the unit air or water cooled?

Norm

[frozensolid]

If this is a multi-head compressor, also check head temp at each head with your IR.

[kooltek]

You say you have injection subcooling, are you talking into the compressor or liquid line subcooling? What kind of compressors? If you have scrolls with the injection valves,or demand cooling. make sure the liquid header which feeds the injection valves has a full column of liquid at all times. Take off should be before any type of modulating valve(such as a defrost regulator). Also if you have a rack controller and extra spare input points, you might try putting a suction and discharge sensor at the compressor and set up a trending report. That way you can see what's happenin' at all times when ur not there. Or you could just plain old have bad valve plates if they are recips.