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Centrifugal rtu

Discussion in 'Commercial' started by pintofstout, May 31, 2017.

  1. pintofstout

    pintofstout New Member

    Messages:
    1,551
    Location:
    Olean, NY
    I saw a unicorn. I followed it up a mystical path, where i found the end of a rainbow. Under the rainbow was a 195 ton magnetic bearing centrifugal compressor powered Aaon rooftop unit.

    It was just too big to get pictures, but i did get one or two from inside the compressor room.

    Very cool.

    [​IMG]
    [​IMG]




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    Tap likes this.
  2. pecmsg

    pecmsg Junior my ASS

    Messages:
    21,222
    Location:
    Eastern LI
    I see a lot of copper............
    No issues with Sweating?
     
  3. pintofstout

    pintofstout New Member

    Messages:
    1,551
    Location:
    Olean, NY
    That big copper is discharge and liquid


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  4. flange

    flange Act like you care and do SOMETHING!!

    Messages:
    12,876
    Location:
    IMT--in my truck
    the copper you are seeing is discharge line and liquid lines going back to the various circuits. Should be fine.
     
  5. flange

    flange Act like you care and do SOMETHING!!

    Messages:
    12,876
    Location:
    IMT--in my truck
    AAON "may" regret the copper discharge. A lot of what we see has gone to steel on the discharge. Something about the resonant frequencies created by the gases leaving the compressor under differing conditions causing leaks.
     
  6. pecmsg

    pecmsg Junior my ASS

    Messages:
    21,222
    Location:
    Eastern LI
    I see a drier, solenoid then X-valve in the background.

    Can only blow up so large
     
  7. frozensolid

    frozensolid Psychologist's Dream

    Messages:
    12,284
    Location:
    Earth
    I took the Turbocor class and all I got was this stinkin (but Cool) Trinket
    turbocor.JPG
     
  8. pintofstout

    pintofstout New Member

    Messages:
    1,551
    Location:
    Olean, NY
    I like that trinket. That things pretty neat actually


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  9. flange

    flange Act like you care and do SOMETHING!!

    Messages:
    12,876
    Location:
    IMT--in my truck
    The small drier which they piped in BEFORE the solenoid? hard to tell what that is for, but my guess is it has to do with the motor cooling of the compressor. The inject refrigerant to keep the electronics cool. If you look directly at the compressor, there is an inverter board under the top black plastic cover, then control boards under the side covers. The "major failures" they had early on were due to placing those boards directly on the compressor and then injecting liquid in with no control. The sweat like pigs and zapped the boards. Lessons were learned and now they use standoffs and refrigerant control to eliminate condensation.
     
    pecmsg likes this.
  10. frozensolid

    frozensolid Psychologist's Dream

    Messages:
    12,284
    Location:
    Earth
    Spin it and it spins for like 10 minutes or more
     
  11. flange

    flange Act like you care and do SOMETHING!!

    Messages:
    12,876
    Location:
    IMT--in my truck
    I used to keep one in my truck for demo, but dropped it and broke the glass. I never cared enough to get another one as we now do live demos on chillers we installed.

    P.S., no monitoring software at least?
     
  12. Catpower

    Catpower The Crowd Pleaser

    Messages:
    22,341
    Location:
    in the Cabana
    First thing I noticed was the chair and the stool, slide the chair out about 8.3849 inches from the wall, so the back of your hear rests on the Armaflex on the line behind it, bring stool close enough to chair to support your legs, and it is a perfect place to take your post lunch snooze :lachen::lachen::lachen:
     
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  13. mike1020

    mike1020 entitled millennial

    Messages:
    18,344
    Location:
    on the roof of target
    First thing I noticed was the chair also.

    A walk-in cooler at target used to have a blanket and pillow hidden above it because their PMT maintenance guy would go up there and sleep all day.
     
  14. flange

    flange Act like you care and do SOMETHING!!

    Messages:
    12,876
    Location:
    IMT--in my truck
    we serviced a rink where the facility guy would clock in at like 6 am, make the ice cuts, do the rounds in the chiller plant, empty trash cans and so forth, but could never be found when you actually needed him. after probably two or three years, they were replacing dasher boards and had to remove a few sections of the stands. underneath they found a mattress, comforters, pillows. dude was checking in, doing some quick rounds then going back to bed!!!
     
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  15. Bustawrench

    Bustawrench Knucklehead

    Messages:
    10,949
    Location:
    South Jersey
    Nice! Those compressors are pretty easy to work on. The only thing you need to be careful of is the DC Bus voltage under that cover. It runs around 650-700 volts, iirc.

    Biggest problem I saw with them was the DC converters don't like power spikes, they burn up before the fuses can save them.

    Also, they don't like power failures durng operation, you only get so many and then the shaft demagnetizes and you have to replace the compressor.
     
    oroy54, pintofstout and mike1020 like this.
  16. HMD

    HMD does it matter?

    Messages:
    93,445
    Location:
    here
    junk
     
  17. flange

    flange Act like you care and do SOMETHING!!

    Messages:
    12,876
    Location:
    IMT--in my truck
    I really admire your tenacity and opinions on this subject. It takes me back to the days of working on heavy metal. At one time, the contractor I worked for had EVERY large centrifugal in the city, or so it seemed. I worked in a division that only saw 1500 tons and up. Punching tubes back then took weeks per machine. All of that said, in todays economic climate, these compressors do serve a purpose, and actually do it quite well. Consider this application alone.... a single 195 ton compressor, infinitely variable down to about 15% of load. It is very electrically efficient, and good for the end user as well as the utility in using killowatts wisely.
    My gripe.....a single compressor, when its down, is not good. I would want redundancy.
     
    mike1020 likes this.
  18. frozensolid

    frozensolid Psychologist's Dream

    Messages:
    12,284
    Location:
    Earth
    I agree with HMD on this one. Maybe in time they will improve. Can't use blends. They are touchy touchy about everything. And as mentioned power failures rapidly wear the device that prevent the rotor magnetic bearing from colliding with the fixed magnetic bearings. Great theory but in practice not so much as yet. JMHO
     
  19. pintofstout

    pintofstout New Member

    Messages:
    1,551
    Location:
    Olean, NY
    I think this application illustrates that there are benefits beyond efficiency alone. This has a DX coil and that is super cool.

    All of the problems presented by oil and the need to return or contain it go out the window. I think there's a lot that hasn't really been thought up or applied yet.

    The more they get out there, the cheaper and better they will become. I like them, chattery check valve and all.


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  20. flange

    flange Act like you care and do SOMETHING!!

    Messages:
    12,876
    Location:
    IMT--in my truck
    I've got machines in for six plus years ( the first one in 2005) with none of the aforementioned issues, some of which are in NJ which is Notorious for power problems. How long do I wait for the problems to occur that everyone warns about?

    To date, we have seen exactly ONE compressor issue. The issue was created by the local carrier office, whose tech didn't know how to work on the machine and he started swapping boards. He failed to do bearing calibrations, so the compressor shafts would get out of kilter. Putting the boards back and doing bearing calibrations saved the client the 300k that carrier wanted for a new chiller, since this one was "a piece of crap". That was four years ago, its still running fine.

    Are they going to take the place of say a two compressor cvhf running 1800 tons, doubtful. do they serve a purpose? Sure.

    I can remember a time when carrier screws were the scourge of the industry. They repeatedly faulted on oil failures and guys tried everything to keep them running. It was early, and few knew about the issue with the inlet screens behind that big old hex plug, and dirty manufacturing in mehico. Once the word got out and guys actually changed them as they were supposed to do, them achiness ran much better. My point......lack of understanding doesn't make a bad product.

    Funny story.....a guy I knew from servicing rinks here moved to a large university in Texas to run their facilities, due to his wife taking a job there. They had carrier screws that the carrier office there couldn't keep online. The carrier dudes were out there DAILY to reset the machine and couldn't figure it out. My buddy called me and asked if I would fly down to have a look. When I asked what machines were there and he told me, I laughed. Carrier screws, no one had ever changed the inlet screens. I told them about it and the local dude went to the factory for confirmation. They quickly changed the screens and the machines ran fine from there on out. I could speak negatively about the machines, but it was really a lack of technician knowledge.