Food for thought, don't forget the vane arm assembly. While leak checking take the linkage loose and manually exercise while leak checking.
Update- Just starting annual maintenance on this machine this week..... tubes,oil,filters,tower,pumps,strainers,etc...You guys know the drill. Ive been out of town for a few weeks so I'll respond to the last 3 or 4 replies. The 2 seals that failed were worn and showed signs of excess heat, orings were fine, L.S.thrust checked, new seal pressure reg. installed. I have manually exercised the vane arm while leak checking. I will probably leak check again on Tuesday and after reading jayguy's reply I think I will blow all of the oil out of the sump and get as much oil out of the purge and lines as possible and focus more attn there. Again thank you all for taking the time to respond, it is appreciated.
We have had the oil cooler lines leak on use as well. To prevent the unit from taking on air while not in use you may want to install a prevac system. It will keep the air out, allow to leak chek, and service it without pulling the charge.
PreVac? Hmmm, I might would consider the version with the water heater and recirc pump, but I wouldn't want those blanket heaters on my chiller. But I would worry that the PreVac would "hide" any leaks, especially high side leaks, while the chiller is off. A good operator will inspect and log a chiller at least once a day (shutdown or running), and will verify that a shutdown chiller is at the pressure that it should be, for the temperature that it's at. To determine if it has air, if it's a low pressure machine. The ability to leak check and service is nice, though.
I agree the chiller should be checked every day by the operator. The prevac allows the unit to be serviced or leak chekced easily after being installed. For hard to find or small leak in the chiller it can save on the repair until it becomes worse. We have several of the units in service and have good luck with them. I would not use the blankets either. You can also put them on a two whell dolly and use them at multiple locations.
If it has the original purge, check the purge exhaust check valve when it is in a vacuum. The solenoid valve will prevent leakage when under pressure, thus no leak to detect. Bad check valve will let air leak in after machine shut down when it's in a vacuum.
Just stick your gauges on check valve flare after shut down and watch for vac.
Or just put a spit gob on it! It will show quick. Or take it off and test under pressure, should have no leakage.
Update = I extensively leak checked the machine once more and again found nothing. Just before I started attaching the explosive charges to the machine I remembered what jayguy posted about purge leaks being hard to find due to the oil , so I shut the machine down after the purge went through its drain cycle , took the oil out of the machine , and made sure all oil lines were drained. I pressurized it and started leak checking again and about 5 minutes in I.................yes I did , I found the leak. So you ask where was it (DRUMROLE PLEASE)... on a flare fitting on one of the purge solenoids. It was a substantial leak = leak detector screamed on the large setting and bubbles galore. You know the crazy thing is Ive checked that particular fitting both electronically and with soap probably 15 times , never picked up a trace , not a single bubble , and not a drop of oil on or under the fitting. I am relieved. Thanks to all that posted.
We have a couple of 500 ton YT with hard to find leaks. I started to leak check one today but no luck picking up a trace with my electronic. I brought up system up to 7psig. I will try tomorrow to check areas suggested in thread. Customer noted that units run fine until off for about 3wks. After extended shutdown then units have excessive air.
Question? Any tips for removing oil from purge with minimizing mess? Any other suggestions/tips? The thing I don't like about these chillers is not being able to remove excessive air with OEM purge. I will pick up our purifier purge from shop to do that job.
if the machine is running, pull wire #61 off the terminal strip. That deenergizes the oil solenoid and the oil returns to the sump. Run for 5-7 minutes and all the oil should be out of the purge and in the oil sump.Quote:
Originally Posted by caddy
Solution to problem: disconnect chilled water and condenser piping, remove incoming power, slide old YT out of room, slide into place a new maglev chiller. No oil, no purge, no ear plugs, low energy consumption, no vibration, happy customer! LOL!I've have had shaft seals that didn't leak much oil but when down for rotation they would go flat. Pulling shaft seal would show oil had "cooked" around seal. Seal pressure regulator at fault each time, either set wrong or trash getting into regulator. If Low speed thrust goes to max limit of spec seal face contact will allow leak after drying out. YKs have software that turns oil pump on every 24 hrs to keep leakage down. More art than science! Keep looking and good luck!