PDA

View Full Version : Centrifugal chillers



reggie
30-04-2002, 07:56 AM
Can anyone tell me any information on centrifugal chillers.
I was recently on a site fixing the comfort cooling when i was approached by the contact asking if my firm would like to take on the maintenance of the refrigeration chillers too. No thanks.
My boss is from that sort of background but im not.
I know all the principles of how they work etc but ive never actually worked on them. Do all operators have to be skilled in tear down work and rebuild??
What maintenance do they require? Whenever ive been on similar sites and seen Trane engineers servicing them they seem to be just recording operating paremeters.
Also if it is specialised how long does it take an average hard working engineer to become competent on them??
Any advice appreciated.

Mike Hopkins
02-05-2002, 03:18 AM
I am quite sure Marc could help you out here and probably teach you many things to help you along the way. The centrifugal machines aren't so different in what they do from any other flooded evaporator machine. Maintenance is fairly straight forward, keep the tubes clean, oil in good shape, oil/refrigerant filters changed, controls calibrated, routine leak checks, etc. and they will run along quite nicely. However, the specialist talent and experience come along when troubles arise, specifically, being able to accurately determine the problem and rectify it quickly. Knowing the in's and out's of all the different micro's and what the different machines need to run correctly i.e. what's this supposed to be and what that supposed to be is where the experience and talent, maybe a little gut feeling or luck come in. If you've never worked with centrifugal, screw, or other flooded evap. machines you would be well advised to do some homework and work with someone familiar with them to get experience. Some little mistakes can lead to tremendous cost rather quickly.
Not only in possible damage to the machine but loss of efficiency or loss of ability to make product or keep a building cool. Any one of which if left unchecked can multiply rather quickly. I have seen some process applications that if the chiller doesn't run = 1000's of dollars per hour in lost production, same with a large building, if it get's too hot then people have to go home or computers get too hot, etc.
Mike Hopkins

reggie
02-05-2002, 07:22 AM
Interesting replies gentlemen and thanks.
Marc im not sure my boss is too keen on getting involved whatsoever and may have already decided to let this one go.
Hes so negative sometimes. I hope hes not reading this, w***er.
Anyhow ill be in touch if and when we need your expertise.
Incidentally Marc do you consider yourself proficient at tear downs??
One final question is that im positive when i scrolled through the microprocessor that these machines were fitted with expansion valves, not high floats or Orifice plates.
My boss claims this is not possible but i think hes getting confused with R11 systems running on low side vaccuums.
These are on R134. Please confirm.