trane tandom scrolls. WHY Trane WHY!?

[lowtemp]

why does trane use tandom scrolls? Dont they know that when one burns out it contaminates the other. Idiots! I know more money for trane. Im just venting ,but what a piss poor design. We wont sell Trane units anymore.

[maintmankc]

does it to. both my 60 ton YPAL units have them.

[Edited by maintmankc on 07-29-2004 at 08:52 PM]

[maxster]

have you come across the Yorks-YCAL air cooled chillers...3 copeland scrolls tandemed one circuit fun on a burn out they leave plenty of room for a 4-core sporlan dryer shell!

[plain spoken]

Originally posted by lowtemp
why does trane use tandom scrolls? Dont they know that when one burns out it contaminates the other. Idiots! I know more money for trane. Im just venting ,but what a piss poor design. We wont sell Trane units anymore.

I guess you must be getting out of the sales business then because all the manufacturer's are doing it.

[mainman]

Have a McQuay four stage/ 2 tandem, 2 tandem, 60 tons total. Also have a York 2 stage, 2nd stage has 2 compressors in tandem.

mainman

[Chomper]

Originally posted by lowtemp
why does trane use tandom scrolls? Dont they know that when one burns out it contaminates the other. Idiots! I know more money for trane. Im just venting ,but what a piss poor design. We wont sell Trane units anymore.

Tandems have been around for as long as I can remember. The first time that I saw one was on a 120 ton ITT-Nesbitt chiller (circa 1975). These had two Copeland semi-herms with a common section opposite the oil pump. They actually worked great.

Now back to 2004.
Cost of manf rules. York and others have it also. I cant recall having a problem changing the compressor in a Trane. The right equipment and couplings make all the difference.
By the way, VENTING is good. Beats taking it out on the family.

[absrbrtek]

The worst tandems use those Danfoss/Manurope scrolls. And you think Tranes a POS, weve lost 3 of 6 in the last two yrs on a YCUL condensing unit. All have been locked up. Real junk there!!!

At least York went to Copeland scrolls with CCHs and discharge check valves on newer models. Failure rate has dropped dramaticaly.

[cynic]

why ? 2 scrolls are cheaper than one semi no wonder they are all going that way.

[lowtemp]

these tandems are in a 25 ton rooftop unit. Trane does it so they can make cheaper evaps and condenser coils(only one header). Another thing about this unit is it is a 575V 3ph unit.They installed a massive 9KVA transformer so they could use 230v 1ph condenser fan motors. This unit was installed in 1999 and all three condenser fans have since burned out and have been replaced.

[bobby m]

ive found some grounded scrolls in trane units that have also blown 6 amp control circuit fuse .fuse protects saftey circuit for compressor internal klixons ,and ive noticed sweating at terminals for klixons on running compressors, ive had units blow this fuse due to sweating .i wonder if this "short circuit" could be enough to "pop"windings at embeded klixon just a thought .

[R12rules]

Semi-hermetics are great serviceable compressors!
Putting them in tandem or any other config is fine in my opinion.
However, there are issues to be addressed and whenever one or more of those issues are in trouble ... then the entire system becomes in trouble.

But .... you substitute a sealed can in the stead of a semi-hermetic ...you are just inviting trouble.

Sure ... tandems have been around a very long time. But, they only work reliably when you put three things together.

1) semi-hermetic compressors, not cans

2) address the issues of tandem engineering

3) preventative maintenance/ proper repair proceedures.


just my two cents worth.

[rob10]

06E's on air cooled carrier chillers are relatively reliable and easy to work on. Multiple scrolls in tandem is just asking for a PIA.