YTJ "Baffling" Baffle issue

[r404a]

York Types:
Got a weird one. Got an 1987 era R11 Centrifugal, 700 tons. Mod#YTJ3K3E3-CVC Ser#YHSM 276200 with a YTH-126 HJ code compressor.This chiller is used as the "summer" machine as they have a 300 ton machine that is the "winter" machine.
I will tell what I know has gone on but am still a little dark on details as I have only run a couple of calls on it. About 1 or 2 years ago, the chiller was overhauled by another reputable shop and sections of the condenser shell were cut to expose the discharge diffuser baffle as they had really loud noises in that section. The baffle was indeed cracked and the contractor rewelded the broken areas. Sometime after the overhaul, the noise returned.

I was out on this chiller last year and found it was low on gas and found A bad leak at the HPswitch captube which had been repaired before and was a result of vibration. Today when I had it started up to check the noise, I noted that the chiller was a bit low on gas and I found that this time a weld on a pipe going to the HP transducer on the shell itself has vibration cracks in it.
At a load of something below 50% FLA the noise coming from the condenser is absolutely unbearable. Above 50% the chiller sounds normal. I have seen plenty of Yorks growl at low loads and even had a YK that had very minimal noises on the same area of the condenser at low loads but NOTHING like this noise. On that YK I did inspect the diffuser and found no issues.
What do you guys say? What would cause that type of failure? Would it be due to running at very low loads?

Thanks for any input

r404a

[milkyway]

York Types:
Got a weird one. Got an 1987 era R11 Centrifugal, 700 tons. Mod#YTJ3K3E3-CVC Ser#YHSM 276200 with a YTH-126 HJ code compressor.This chiller is used as the "summer" machine as they have a 300 ton machine that is the "winter" machine.
I will tell what I know has gone on but am still a little dark on details as I have only run a couple of calls on it. About 1 or 2 years ago, the chiller was overhauled by another reputable shop and sections of the condenser shell were cut to expose the discharge diffuser baffle as they had really loud noises in that section. The baffle was indeed cracked and the contractor rewelded the broken areas. Sometime after the overhaul, the noise returned.

I was out on this chiller last year and found it was low on gas and found A bad leak at the HPswitch captube which had been repaired before and was a result of vibration. Today when I had it started up to check the noise, I noted that the chiller was a bit low on gas and I found that this time a weld on a pipe going to the HP transducer on the shell itself has vibration cracks in it.
At a load of something below 50% FLA the noise coming from the condenser is absolutely unbearable. Above 50% the chiller sounds normal. I have seen plenty of Yorks growl at low loads and even had a YK that had very minimal noises on the same area of the condenser at low loads but NOTHING like this noise. On that YK I did inspect the diffuser and found no issues.
What do you guys say? What would cause that type of failure? Would it be due to running at very low loads?

Thanks for any input

r404a

sounds a little like an issue to me., if it is vibrating that bad to cause cracks,
have u tried a vibration anaylsis
?

[mryan1]

i would go with a vibration analysis like he said sounds like there are other issues, thats alot of cracking going on...even under low load that shouldnt happen.

[york56]

I had one YT that when it ran and had air in it you could only run it around 40-50% and this machine was extremely loud until the air was purged from chiller and you could load it up then it would settle down never broke any baffles you often wonder when these machines surge with the frequency and the amount of times they do that it can't be good for anything inside that shell the older machines us to do this repeated over and over until someone heard it at least the new fail fairly quick now.

[mryan1]

I had one YT that when it ran and had air in it you could only run it around 40-50% and this machine was extremely loud until the air was purged from chiller and you could load it up then it would settle down never broke any baffles you often wonder when these machines surge with the frequency and the amount of times they do that it can't be good for anything inside that shell the older machines us to do this repeated over and over until someone heard it at least the new fail fairly quick now.

yes thats right, when these things go into surge mode, just imagine a squirrel cage if the thing has no whre to throw the air it wont spin, just as in the chiller when the head is exceeded in the condenser the machine has no where to pump the vapor but backwards.

[ChillTek NC]

If it had air in the machine, it would definitely surge when the machine loads up but if you limit the machine and back it down to keep the machine online, may stop your surging and let the purge do its job. Purge only works when machine is running. But your specific noise may be something different. Get a vibration analysis. Best of luck...

[ryjowy]

Is this a codepack? We have a YTJ on an old double ender set of barrels. Tubes are bouncing due to lack of support and higher refrigerant velocities. Needless to say, tubes wore in the supports and now a retube is in the works. Highly recommend the vibration analysis. Take out the guess work.

[r404a]

appreciate all input

r404a

[duke of earl]

You may want to do an eddy current as a result of this. Have you measured the condenser water flow?I've never heard this noise as I have 2 of these under contract. Tell us more about the chiller externals(piping,tower control,etc.)