PDA

View Full Version : high oil temp on a trane rtua



gpass
08-24-2009, 12:24 PM
I am working on a trane rtua 100 chiller and I'm having a problem with high oil temp, my guess is that the txv for the oil cooler is bad? The circuits sub cooling is at 20 deg and superheat is at 9 deg
Oil temp is gets up to 170 deg. I did check oil level and its ok. Am I missing anything in my troubleshooting?

ChillerWisperer
08-24-2009, 02:51 PM
On just one circuit or both? If only one, then how does the oil delta t compare to the other circuit? Are your sc/sh numbers for the oil cooling circuit or the main circuit? How does the filter delta p compare on the two circuits? Are your sensors reading accurately?

gpass
08-24-2009, 03:15 PM
The sh/sc is on the cooling circuit. The problem is only on w circuit (circuit 2) as far as delta t and delta p it is the same except for 2nd circuit is running a much hiher temp.

ChillerWisperer
08-24-2009, 03:46 PM
Assuming you have subcooled liquid to the expansion valve of the oil cooler, how cool is the refrigerant outlet of the cooler? How does it compare to the outlet on the other cooler at similar load?

gpass
08-24-2009, 04:17 PM
I did not compare the temp on the two coolers. The one that I'm having the problem with the temp in is at 170 deg and the outlet is at 168. The solinoid is energized for the oil cooler and the temp before the txv is 90 and 170 after.

ChillerWisperer
08-24-2009, 04:40 PM
You're too high on both circuits. Normal oil temp is around 130. Also your sh should be 4 deg. Check your charge and EXV operation.

Make sure your sat. evap and comp suct sensors are accurate and that your drier cores aren't restricted.

ChillerWisperer
08-24-2009, 05:02 PM
Sorry, I just reread your post and realized the 168/170 was on the same circ. If you're getting 170 on the ref. outlet of the txv, then it's def. closed.

mxwideopen
08-05-2010, 12:54 AM
Sorry, I just reread your post and realized the 168/170 was on the same circ. If you're getting 170 on the ref. outlet of the txv, then it's def. closed.

excellent discussion!!! How did this end? What was the reason, for High oil temp?. I'm having same kind of problem here, too.