19DH carrier Chiller problem

[Morne]

Hi all

Im looking for assistance, we have 8 of these 19DH Chillers on plant and we've done it all, maintenance, OHSA, B-Service(oil change), C-service (motor overhaul) in my years.

Currently we stuck with a problem, After start up chiller run for 15 min to half an hour on full load of 100% then all of a sudden the vane start closing till 0%and thats how it stays. The chiller doesnt trip, it just loses it load. We have been communicating with the supplier and checked the Vane close oil pressure switch if its faulty, but thats seem to be working fine.

Have anyone experienced a problem like this, i know these chillers are ancient. If anyone has problems on there side, i'll be happy to assist, im sure what ever problem you have, we might have came across it.

Thanks

[beenthere]

Moved to Chiller forum.

[turbovac]

have you checked the output of the ct to teminals 23 & 24 in the control
panel? at full load this should be .5 volts, maybe the ct or the resistor in
paralle with the ct output

[referteacher]

Leaving chilled water temperature sensor out of calibration?

[heavymetaldad]

32sm or 3200mp?

[Randy S.]

I know where there's a couple of ESP II panels from like a 19DK that could find their way to surplus if anybody here thinks that would be a good idea.

[Morne]

Hi All,
Thanks for the help, I have checked the Motor Voltage across 23 & 24 terminals and are fine, i have even, just to eliminate any hints, by renewing the Modulator Control box, renewed the Vane Motor, Check the Leaving chilled water temperature sensor, it was with in spec, the vane and oil switch, was with in spec.

We just completed a B-service, i.e Oil service on Chiller a week ago, and the Chiller was running for about an hour before the problem occurred. During the investigation it was found that the sump oil was black, which was strange considering the B-Service was just done(during the service the oil was drained, filters renewed, gromit checked, recharged, poppet valve checked and the sump cleaned). I have sent the oil away to have it checked and still awaiting feedback.

Another option we are exploring, on site it works abit differently, the operators can control the load of the Chiller from the control room, so as cooling demand increases the Load adjusted as required, this however overides the Modulator. We are currently investigating and renewing the Control Pod in the control room. I dont think that it would be the cause of the problem because on start up the chiller runs for 30minutes at full load then starts unloading, but i feel elimanating it would help.

Im really dumb struck on this problem!

[heavymetaldad]

external bas can and will affect machine operation. which micro do you have????????

[local 392]

what's your condenser water temp look like

[pmdolan]

Not sure if this helps, but if you are looking for parts or spares I have three 19DH ( 500 HP) chillers for sale. pat dolan 845 733 7713.

[Rusty49]

I have no idea how your control program is set up, but my experience with the 19 DH is the vanes are modulated open or closed based on Delta T of the leaving water temp of the evaporator as compared to the setpoint and also FLA of the motor. If the load gets to high it will start closeing the vanes. I would look at the amp draw first.
Rusty

[chillerking]

When a 19DH starts the vanes are controlled by the 32sm controller. They will open as far as the current limiter will allow. So obviously the ct's are working. I would start the machine. adjust the load limiter from 100 percent to 75 percent and then to 50 percent proving the 32sm controller load limiter function is correct. the next stpe i would try is putting the load limit back to 100 percent and then adjust leaving setpoint control up, and see if the machine gets control of the load and the vanes back off. If this works the i would adjust the setpoint down further and see if response repeats. THE 32 SM CONTROLLER HAVE BEEN KNOWN TO DEVELOP A DEAD SPOT ON THE SETPOINT FEEDBACK POT.

[Randy S.]

I walked into a 19DA once where the DDC folks had interrupted the CT signal.