We currently have a 1993 300T RTAA that's on it's last leg, literally. Circuit 1 has been abaondoned with multiple small innacessible leaks (right by the frame supports) on the condenser coils that would have to be fixed 100% sinec as lcuk woudl ahve it, the EXV's failed closed some time last year and it blew it's charge out the PRV's. Thanks to new R22 rules, cannot put back in service until 100% fixed even though to loss of refrigerant was mostly unrelated to the leaks. The unit has not had proper service over the years. I don't think the comrpessors have every been rebuiolt sand are well past their service life. So we're down to 1 circuit and abotu 35-40% capacity, which based on the current installed capacity in the building, is plenty. W're at the point where we're robbing condenser fans out of circuit 2 to limp it along.
The application is comfort cooling with one large rooftop air handler (~50-70T), one smaller air handler indoors ~20T, and a handfull of fan coils thate are around 20-30T. We also have a LOT of chilled water piping since it's a old hospital, and much of it now has individual RTU's for each area and an area that's unfinished. The alrge Rooftop unit is probably only at 40-50% capacity sicne we never finished a large part of the building and never will in the near future (just moved a lot of personel to a new building in Chicago)
Our primary vendor locally is Trane. I don't even have any contacts for York or McQuay/Daikin sales people. We do have 3 York Water cooled chiller in our industrial operations. They tend to be a little more problematic, expecially the controls, than the Trane units we have... and of course they scream like a banshee. The other units are 2 Trane screw machines and 4 centrifugals.
I've been looking at a 130T CGAM. I even took a look at one at a Brewery in St. Louis. It looked nice, way very compact and quiet. My lunch and the fresh case of beer I purchased was still better.
Shold I consider some other brand? Anyone have sales office contacts other than what I can look-up online. I do have a comemrical mechainical contractor that we use for our HVAC that can work with most any distributor.
The building currently has Tracer Summit and communicates with the chiller. I'd like to retain this functionality. Nice to remotely see what's going on, saves a trip acorss town most of the time.
Any feedback on CGAM's? What I've heard of McQuay is that they are common in some local schools because they have great efficeincy ratings on paper, and cost less, but are mostly just trouble. For Yor, I think I have to contact someone 4 hours away in Des Moines. Probably the same with Carrier.
I'd like to look as scroll based chiller for the low noise levels, cost simplicity, repair costs, redundancy and size.
Will I have any issues with the existing circulation pump? My Trane rep says no. That the pipe size reduciton alone should reduce flow enough. I figure I might need to cut down the existing impeller or add a VFD.