Reply to Thread

What you can do next chance you work on it is take a meg ohm reading. Supco makes a nice meter that works very well for this purpose. I had a customer years ago that had an extremely noisy little semi hermetic compressor that would shake rattle and roll! I said to him sounds like its going out and he replied "Its been like that for years!."

Take a meg ohm reading record it. Check your superheat 6 inches from the suction service valve. Copeland says you must have a MINIMUM of 20 deg superheat at the compressor. If you do not you will have to adjust your expansion valve.

Some will argue with me but to me the superheat at the compressor is probably the most important test I do. It will determine if the compressor is going to live or die!

Good luck!

Whats that saying ?

Oh yea ...... i told you so

You just might get to use it

Don't run yourself in circles trying to convince them. If you believe it's going to fail and have explained it to them your job is done. It's their money. Spend it how ever they want. If you push too much they may think your a salesman trying to make a bonus and not trust you. Fill out your invoice with detail as to cover yourself and walk away. When it burns out fix it and charge them for every second and every wire nut. Sometimes you gotta let a hard headed kid go ahead and shove the fork in the electric socket to understand. Cleaning a severe burn out on a rack is time consuming and expensive and they may have to feel that pain to understand. Good luck.

Originally Posted by jpsmith1cm

This.


If this is a rack system meaning a parallel rack system where all of the compressors share the load on a common manifold, then you're probably not looking at start windings.

The "woo woo woo" sound you're hearing is probably a regulator valve or a check valve feeding or whistling.

It is very difficult to convince customers to spend big money on compressor replacements as a pre-emptive measure.

I appreciate all the input for sure, this definite has start windings start capacitors, potential relays not 3 phase and not to say you are off base about the regulator valves but all my cases are keeping temp and when I bring this compressor off line the noise goes away, I was afraid it was in the cooling fan assembly so I disconnected the power to them and listen to it run. Seems to be in the compressor to me. I certainly do not want to misdiagnose this problem though, so something specific you are reccommending me to look at. Compressor Replacement cost is about 3 grand and can anyone give me a ball park of a minimal burnout clean up cost. Never had to do burnout cleanup on a large system.

Originally Posted by craig1

You have a 9 compressor rack thats single phase ? (start windings)

The Woo Woo Woo and other similar noises are harmonics that result from the abnormal vibration of the bad compressor interacting with the normal vibrations of that compressor and other compressors.


If its one of the med temp compressors, I would shut it down until its fixed. It probably doesn't need all 7.

This.


If this is a rack system meaning a parallel rack system where all of the compressors share the load on a common manifold, then you're probably not looking at start windings.

The "woo woo woo" sound you're hearing is probably a regulator valve or a check valve feeding or whistling.

It is very difficult to convince customers to spend big money on compressor replacements as a pre-emptive measure.

For starters you will need compressor, start components, Driers, a lot of screens, If it was a slow burn you will see it through system, I have seen some devices need to be unsweated to clean or replace as in epr`s,cpr`s HGB`s the list goes on. If they get crap and acid you will need to keep changing driers after initial clean up.

Originally Posted by craig1

You have a 9 compressor rack thats single phase ? (start windings)

The Woo Woo Woo and other similar noises are harmonics that result from the abnormal vibration of the bad compressor interacting with the normal vibrations of that compressor and other compressors.


If its one of the med temp compressors, I would shut it down until its fixed. It probably doesn't need all 7.

Yes, I have reccommended taking it off line til I can order a new one and fix it but they know the system can run on less as much as I do so they want to wait til it crashes. I have little experience with actual burnouts in a rack system so know this is a bad idea, but do not want to let them cost themselves money that would not have to spend. Chances are the compressor will lock up instead of actually burning up, but need to educate them on the cost of potential damage. Customer sometimes in charge so much it is to their own demise.

Originally Posted by Darby,MT

Woo Woo Woo which in my experience has been the start winding lagging. I am open to input on this as well.

You have a 9 compressor rack thats single phase ? (start windings)

The Woo Woo Woo and other similar noises are harmonics that result from the abnormal vibration of the bad compressor interacting with the normal vibrations of that compressor and other compressors.


If its one of the med temp compressors, I would shut it down until its fixed. It probably doesn't need all 7.

Originally Posted by Phase Loss

what is the sign leading to a burnout?

Woo Woo Woo which in my experience has been the start winding lagging. I am open to input on this as well.

what is the sign leading to a burnout?

Will just inform them there is a compressor that is abnormally loud. Tell them you made sure oil level is ok and it passed your acid test but not to be surprised if it locks up.

Convincing a Customer of the Dangers of Risking a Compressor Burnout

Convincing a Customer of the Dangers of Risking a Compressor Burnout



I have a customer that is a resort with a small 9 rack system with 7 medium temp 2.5 horse compressors and to low temp compressors. One of the compressors is on its way out become very loud and showing symptoms a possilbe burnout to come acid test are clean right now, but I am trying to educate the customer about the dangers of burnouts in a rack system, and the benefits of changing the compressor now to save them the money. They are very in charge types and I need some literature to back me before our meeting can anyone help, with literature that can illustrate the cost of waiting for this compressor to burn out and having to clean the entire system up.

Thanks

Will