Rtaa 170

[nique]

I blew the b comp today and need to make it so a will run, only prob is that all the b alarms shut it down. How do I do this in the controls.

[nique]

Sorry I was in a hurry, I need to get comp a to run but all the alarms shut down the circuit. Is there a way to make it so comp b never tries to start? It is a rtaa270 with adaptive control

[CV_Geardrive]

Hi,
If in A! circuit you have 2 compressors, a fault from one compressor stops also the other.
You cannot start only one compressor and it is not good to start it if the other one is burned out.
It is possible if you make a lot of changes in control cables and programming but it is not recommended.
You should only run B! circuit.
Regards,
CV

[valdelocc]

Sorry I was in a hurry, I need to get comp a to run but all the alarms shut down the circuit. Is there a way to make it so comp b never tries to start? It is a rtaa270 with adaptive control

There is a way to do it, go to service settings, look for compressor "b" "unlock" and change it to "lockout", press "next" then "enter" and you are good to go.

[R123]

There is a way to do it, go to service settings, look for compressor "b" "unlock" and change it to "lockout", press "next" then "enter" and you are good to go.

If you have a compressor failure you need to do more than simply letting the controls lock it out. You need to physically disconnect the compressor leads. If the chiller has the Cutler Hammer contactors, you can remove the contactor head.

[nique]

I read that manual for half the night and never saw a thing for compressor lockout, what p# is it?

[R123]

I read that manual for half the night and never saw a thing for compressor lockout, what p# is it?

P1A
IOM 3 page 94. That's for circuit lockout, there is no compressor lockout but since this chiller has only 1 compressor per circuit, circuit lockout will do.

[nique]

That's the problem circuit 1 has two comp. "A" is a 100 ton and "B" is a 70 ton. Circuit 2 has "C" which is a 100 ton. I've taken "B" completely out of the circuit but the controls don't know that. The readout is before the one with next and enter. Just the up, down and side arrows.

[R123]

That's the problem circuit 1 has two comp. "A" is a 100 ton and "B" is a 70 ton. Circuit 2 has "C" which is a 100 ton. I've taken "B" completely out of the circuit but the controls don't know that. The readout is before the one with next and enter. Just the up, down and side arrows.

Ok, I thought it was a 170 ton as per your 1st post but in your 2nd post, you said 270 ton. The only thing you can do is create a compressor alarm such as making the oil pressure switch show tripped and that compressor will lock out in alarm but you need to also physically disconnect the power wiring at the contactor (or pull the contactor head) so there is no way the compressor can start.

[nique]

I've taken the compressor out both refrigerant and electrical. But when any alarm for that compressor comes up the whole circuit drops. I tried the oil switch with the same result. Any other ideas?

[valdelocc]

Have you tried changing the number of compressors in the "machine configuration" menu?

[nique]

I did, also stages.

[valdelocc]

Well, its time to take a drive to your local Trane office and have them call chiller tech support, make sure to bring some Snickers. .....and please let me know the rest of the story!

[gbrlgms]

what type of control panel for the rtaa (ucp1 or ucp2)if is a ucp1 there is hidden menu,menu 4,5,on menu 5 you can change the number of compressors and compressor tonnage,maybe that will work

[gbrlgms]

[nique]

did that to, no luck. it seems like common sense would say that what i want should be easy to do but! I was just hoping that somebody on here would know.
for the rest of the story as best i can figure it. the compressor contactor stuck which caused the compressor and all the wires to overheat. the fuses are good for all three compressors and only one of them blew. thus the unit ran untill all the wires in the unit, the disconnect and the first two floors caught fire. the compressors blew the terminals and i had one heck of a mess. so all sunday was pulling new wire, getting new fuses, isolating that compressor and getting the chiller back on line. I never bothered to look and see if dropping the bad compressor out was an option until all the hard work was done. somehow i got it, not sure how but A and C stayed running all day. new comp 3 days out and another weekend down the drain. gotta love this business.

[nique]

it is a ucp1

[CV_Geardrive]

Hi,
As B! compressor is off you have to do the following. (You will need RTAA –IOM-3)
Set address of B! compressor module to compressor C or D.
Set address of C! compressor module to compressor B!
As A! compressor module has fan control and CDS SAT temp sensor there is no problem.
Expansion valve module #1 has the 1st expansion valve of A! circuit and 1st expansion valve of B! circuit and also has the saturated and suction temperature sensors for both circuits, so there is no problem.
Set the unit to 2 compressor configuration. (2 circuits, 1 compressor per circuit)
Set the unit to 1 expansion valve per circuit.
Start the unit.
If B! compressor is burned out you may have l have a low oil flow alarm for compressor A!. You may need to replace oil and oil filter more than once.
Once again above procedure (with one compressor burned out) is not recommended.
Hope it was helpful.
Regards,
CV

[CV_Geardrive]

Don't forget to check overload settings as compressors are not same size.