Trane RTHB-300 issues

[rookie_fitter]

I have 2 RTHB-300 Chillers Lead-lag, that are tripping off on severe phase unbalance. Checked all amps, voltage, and had a power study done on the building. The only thing that we have noticed is that the amps read off of my clamp on meter does not match what the ct's are picking up. All of the ct's ohm out the same. The only thing I can conclude is that the 2u1 starter board may have issue. Any ideas and/or input would be great!

[DrumCrazy]

RTHB service bulletin 5 chapter 4 --- you need to do more than ohm the ct's -- I can't upload the pdf for some reason.

[maxpower]

What is the actual percentage?

[Manu1]

If both chillers are tripping on phase unbalance have you checked what is the real unbalance? This controller is design to trip when the curretn unbalance is above 25% are you sure they are not doing what they are supposed to be doing?

[rookie_fitter]

Drum Crazy, Thanks for the help, it took three calls to the local trane dealer before they acknowledged that such a bullatin existed. I found that the chillers had never been commisioned and all of the perameters where off.

[drivewizard]

Drum Crazy, Thanks for the help, it took three calls to the local trane dealer before they acknowledged that such a bullatin existed. I found that the chillers had never been commisioned and all of the perameters where off.

Interesting, who did you talk to, receptionist, parts guy,??
You need to ask for service manager in situations like that.
As far as chiller never being commissioned, whose decision was that?
Sometimes mech contractors feel they can save those $$$ and do it themselves. Then it never gets done or done properly.
We would like to commission all equip we sell, as it is our reputation on the line. Sometimes a non-factory start-up consists of throwing the disconnect on and making sure equip starts. Then if it crashes, they call for warranty service. Can't feel to sorry for them at that point.

[r404a]

Interesting, who did you talk to, receptionist, parts guy,??
You need to ask for service manager in situations like that.
As far as chiller never being commissioned, whose decision was that?
Sometimes mech contractors feel they can save those $$$ and do it themselves. Then it never gets done or done properly.
We would like to commission all equip we sell, as it is our reputation on the line. Sometimes a non-factory start-up consists of throwing the disconnect on and making sure equip starts. Then if it crashes, they call for warranty service. Can't feel to sorry for them at that point.

around here anything watercooled, air cooled over 25 tons (possibly all air cooled) and Voyager III and up must be started by Trane. I have a hard time believing an RTHB was not factory started. Soundslike someone has been in that UCP2 changing things.