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Salmon_king
02-02-2010, 11:46 PM
Can someone tell me if there is a reason why McQuay does not face their tubes? I have a condenser end that is collecting a lot of debris on the face because the tubes are sticking out a couple of mm's. All Trane's tubes are faced. Can I use a facing tool to bring them down to the tube sheet or am I asking for trouble?

klove
02-03-2010, 11:37 AM
Money

Octopus
02-03-2010, 04:47 PM
Consult MCquay in writing so it you do get trouble and they do say go do it you have something in writing. BTW they are never going to say go ahead.

klove
02-03-2010, 05:16 PM
I agree with the sentiment, chris, but it's not McQuays responsibility if someone else decides to face the tubes.

As far as technically difficult jobs go, salmon, tube facing ranks somewhere between changing the washers in your water hose and blowing your nose, but it certainly has it's share of risk. Call one of the tubing tool companies, get a facer, and pack a lunch - it's gonna be a long and boring day. Be careful and it will be accident and uh-oh free.

Lots of mfrs don't face tubes for various reasons, mainly first cost. If I were you, I might think about a pressure washer if it's simply debris. 2 mm ain't much to hang up in, so it can't be that hard to clean. If it's actual buildup on the tube sheet, you may want to scrape it down to metal and see if the steel is being eaten away. Could be time to call in the belzona folks and have the end sheets coated.

poppop
02-03-2010, 05:21 PM
what klove said....

Salmon_king
02-03-2010, 11:21 PM
Thanks for your thoughts. I had sort of the same opinion but I was asking on behalf of one of my co workers. He thought we could get a recommendation from the factory. I think that would be wishful thinking myself. Why would McQuay stretch their neck out on this one? It is what it is.

The problem is the facing tool is going to get beat up pretty bad if there are lumps growing all over the sheet. I have faced a few sheets myself and if you don't have a nice clean sheet and you catch something you blunt the tool. Then it looks like the tubes have been beaten with a hammer.

duke of earl
02-10-2010, 10:36 PM
I wouldn't scrape those deposits if I were you. If the tube sheet is thin where you scrape, you may remove enough material to cause a problem.

klove
02-10-2010, 10:45 PM
I wouldn't scrape those deposits if I were you. If the tube sheet is thin where you scrape, you may remove enough material to cause a problem.

I don't understand this statement. If it's corroded to the point that the corrosion is the only thing keeping it from leaking..........that ain't gonna happen. And if it's corroded to the point that you need to figure out what's going on so that repairs can be made if necessary, how are you going to accomplish that without scraping part of it to bare metal?

btuhack
02-10-2010, 11:06 PM
I can see it being a noteworthy comment on a work order/annual report, but from a risk/reward standpoint, why open a can of worms that the mfg considers normal. Is the barrel so new and the condition so bad that a premature re-tube is eminent? or is this condition just part of the mcquay life cycle.

Salmon_king
02-10-2010, 11:54 PM
It is more of a buildup problem than a corrosion problem. I have always left it there. I have found that if it is actual corrosion it will fall off on its own while you are doing the tube cleaning. Over time you begin to see more and more material missing and the tubes seem to be sticking out more. My co worker thought I could find an official recommendation but I agree it is highly unlikely.

york56
02-11-2010, 05:26 AM
Why don't you have them epoxy coated that will reduce the amount of tube sticking out , you could also install an anode to help with the corrosion. Why is all this debri in there if the water treatment is good.