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Dave_87
11-13-2009, 07:02 PM
unit is going off on "oil flow control" both compressors. unit does not have oil flow control or oil pressure switch. it is monitored by temp. thermistors. This diagnostic code is not in the book. Does anyone know what this is?

Healey Nut
11-13-2009, 07:10 PM
You will never guess..... you have low oil flow ?????

chillrdude
11-13-2009, 08:27 PM
Something doesnt add up here Dave, you say you have a RTAA125 and you are correct they have temp sensors that verify proper oil flow, on RTAAs from 130 tons and up they have a oil differential pressure switch that the micro "tests" every time it stops a compressor, if the oil switch doesnt pass the test it alarms out with "oil flow control".

Your RTAA 125 should alarm with oil system fault, are you sure of what machine you have here. If it is a RTAA125 or smaller it will have a clear language display where you actually read the alarm messages, if it is a RTAA130 and up it will have a blue LED screen that will give you a diagnostic code that you have to cross over on a chart.

Which book do you have? RTAA125 and smaller is RTAA-IOM4A and the RTAA130 and up is RTAA-IOM-3 at least thats what they used to be.

ChillerWisperer
11-13-2009, 09:33 PM
This diagnostic code is not in the book.

Yes it is. Take another look at page 96. Assuming you're looking at the right book to begin with.

Tranetek
11-13-2009, 10:44 PM
Oil temp is falling more the 4 degrees below sat cond. temp. Check all sensor for correct readings and check to ground. If there is any reading to ground you should change the sensor. You are more they likely slugging ref. back and cooling the oil. It is usually a bad sensor.

Dave_87
11-13-2009, 10:55 PM
Yes. I have a RTAA 1254 and looking at book RTAA-IOM-4A and the clear language display reads "oil flow control cprsr A". Its not reading "Low oil flow" or "oil system fault". The unit will run about 5 to 10 minutes somtimes or it will run 2 hours then shut down on this code.

Dave_87
11-13-2009, 10:58 PM
if it was a sensor problem would it have to run for 30 minutes before shutting down on " oil system fault"

Dave_87
11-13-2009, 11:04 PM
the clear language display shows " oil flow control" not " oil system fault" like on page 96

Healey Nut
11-13-2009, 11:10 PM
Dirty coils

referteacher
11-13-2009, 11:12 PM
the clear language display shows " oil flow control" not " oil system fault" like on page 96

Check you configuration. Sounds like you have the wrong compressors configured.

I had one like that a while ago. Everyone kept thinking it was an "Oil Flow" problem where the wording is actually "Oil System Fault" .

Found the controls were configured for the wrong compressors.

Dave_87
11-13-2009, 11:13 PM
I cleaned the coils thursday

referteacher
11-13-2009, 11:18 PM
Yes. I have a RTAA 1254 and looking at book RTAA-IOM-4A and the clear language display reads "oil flow control cprsr A". Its not reading "Low oil flow" or "oil system fault". The unit will run about 5 to 10 minutes somtimes or it will run 2 hours then shut down on this code.

Sorry, Grabbed the wrong quote. I meant "Oil Flow Control" fault, like you said.

Healey Nut
11-13-2009, 11:26 PM
Do all the fans run and are they going the right direction ?? you say you cleaned the coils , the oil cooler is in the top passes of the coil are they REALLY clean ???

Dave_87
11-13-2009, 11:26 PM
what if they are configured for the " CHHN " compressor like what is in the unit. can u think of anything else?

Dave_87
11-13-2009, 11:28 PM
I took extra time on this chiller to make sure the coils are clean. Fans do work and right direction. Head pressure is around 200 psi

Healey Nut
11-13-2009, 11:31 PM
Well if the config is right ,the coils are super clean ,the sat condenser and oil temp sensors are correct then it would have to be dirty oil filters ??

Dave_87
11-13-2009, 11:39 PM
pressure drop across oil filter is 4 psi

referteacher
11-13-2009, 11:44 PM
what if they are configured for the " CHHN " compressor like what is in the unit. can u think of anything else?

I can't remember the exact lettering of the compressors. I think there are only two models. Ours were configured for the opposite compressors than were actually on the machine.

It was a situation where we took over a contract when the chillers were a couple years old and then mysteriously they started having this "Oil Control Fault" problem. How do you suppose that happened? You don't think the previous contractor was a little disgruntled they lost the contract?

Just like you, they would run for several hours, and then when they'd cycle off the alarm would show up.

Chillrdude explains exactly how it works. The controls test for oil pressure control integrity at each shut down.

Go through the entire configuration and make sure it's configured for the machine you actually have.

Dave_87
11-13-2009, 11:50 PM
Ok. I'll go through the configs again. Your right there are only two " CHHN and CHHB".

referteacher
11-13-2009, 11:56 PM
Ok. I'll go through the configs again. Your right there are only two " CHHN and CHHB".

That's it.!!! Been a while. This one was configured for CHHB when it actually had CHHN compressors. Gotta read the diagnostics word for word. Some times what you think you're reading, isn't what it's saying.

Good luck and let us know what you found out.

Dave_87
11-14-2009, 12:13 AM
I'll check it in the morning and let ya'll know.

Dave_87
11-14-2009, 11:19 AM
You was 100% correct. I give you an adiboy!!!! Thank you so much for you help!!! Configured for 200 ton chiller and chhb compressor.

Healey Nut
11-14-2009, 03:52 PM
Moral of the story....... post the exact information and readings and you will get to the root of the problem much faster .

referteacher
11-14-2009, 04:07 PM
Moral of the story....... post the exact information and readings and you will get to the root of the problem much faster .

Actually, He did in his very first post. We just didn't read it correctly. Sometimes what you think you saw, isn't always what's really there.

RTAA 1254 trane chiller

unit is going off on "oil flow control" both compressors. unit does not have oil flow control or oil pressure switch. it is monitored by temp. thermistors. This diagnostic code is not in the book. Does anyone know what this is?

Healey Nut
11-14-2009, 04:23 PM
Your right he did . Sometimes you cant see the forest for the trees .

Dallas Duster
11-14-2009, 04:28 PM
Come on you Trane guys yall are slipping a little bit on this one !!!! :ghug:

jayguy
11-14-2009, 07:37 PM
Come on you Trane guys yall are slipping a little bit on this one !!!! :ghug:

2 words...OU and CH!!

jayguy
11-14-2009, 07:50 PM
can't find my RTAA class notes on this...but if i remember it right...

RTAA-SB-9, page 10-27

the J3-1 and J3-2 inputs on the compressor module are jumpered because they originally had on oil pressure switch input and it was these 2 inputs but they never went with it. legend has it that trane was going to have the "new" boards (UCP2 style) available for the older UCP1 units (130 tons and larger) and that never happened but they still had all of the old compressor info in the programming.

for the UCP1 units: diagnostic 1A5 is "Oil Flow Control - compressor A" which is where the unit is looking for the open switch at shutdown. it appears that they even moved the old diagnostic codes over to the UCP2 in programming...which begs the question...could you convert a UCP1 control system to a UCP2? it appears that with enough digging you might...but i never told you to do that.

txhvac
11-15-2009, 12:38 PM
can't find my RTAA class notes on this...but if i remember it right...

RTAA-SB-9, page 10-27

the J3-1 and J3-2 inputs on the compressor module are jumpered because they originally had on oil pressure switch input and it was these 2 inputs but they never went with it. legend has it that trane was going to have the "new" boards (UCP2 style) available for the older UCP1 units (130 tons and larger) and that never happened but they still had all of the old compressor info in the programming.

for the UCP1 units: diagnostic 1A5 is "Oil Flow Control - compressor A" which is where the unit is looking for the open switch at shutdown. it appears that they even moved the old diagnostic codes over to the UCP2 in programming...which begs the question...could you convert a UCP1 control system to a UCP2? it appears that with enough digging you might...but i never told you to do that.

Funny you mention that Jay, after reading the these threads, I thought the same thing. I've never had anybody screw (no pun intended) around too much with the machine configuration, to where you'd get to that point. I had a 150 ton RTHB think it was a 300 ton, power outage wiped the chiller mod. tripped on alot of crazy faults, before resetting the field-s/u & machine configs. Fun stuff. Good brainstorm on this one.

referteacher
11-15-2009, 04:09 PM
You was 100% correct. I give you an adiboy!!!! Thank you so much for you help!!! Configured for 200 ton chiller and chhb compressor.

txhvac: I had a 150 ton RTHB think it was a 300 ton, power outage wiped the chiller mod. tripped on alot of crazy faults, before resetting the field-s/u & machine configs. Fun stuff. Good brainstorm on this one.

Still can't sleep, thinking about you, Dave. Hope you verified ALL the configuration points AND dip switch settings to make sure they are all set to the right points for the machine you actually have.

Anyway. I don't think anyone said: "Welcome to the club". You brought up a good situation to start and precicely spelled out the problem ( though it took us old-farts a while to recognize that). Hope you keep contributing to our discussions.

Dave_87
11-16-2009, 01:30 AM
Thanks again. Thanks for the welcome and I will be active in the discussions. Maybe even help someone myself or learn more on some crazy fault codes..... By the way Chiller still running good.

milkyway
09-28-2010, 09:03 AM
You will never guess..... you have low oil flow ?????

ur silly as hell graham cracker., haha::DD:

Tech Rob
09-28-2010, 10:45 PM
If you get in the habit of logging the setpoints and settings in using the log sheet in the IOM, in addition to logging the running info, even the most minute changes to the unit setup jump right out at you once you put it on paper.

There's a spot on there that says "compressor model no. prefix" and "compressor tons"

milkyway
09-28-2010, 11:07 PM
100 % true., great advice