20 year old ac compressor replacement for high rise bldg 1

[sailoday28]

I'm told that motor has to be same as original equipment. I would hope to replace motor with one of high efficiency. Carrier AC model 38AE044570. Is it possible?

 

[ElSid1]

Not worth it. The technology has changed that the compressor itself are MUCH more efficient. A chillers "usefull" life, per ASHRAE is 22 yrs.
This will also allow for some "reverse engineering to verify that the loads are correct. Doing a central plant at the moment. Replacing the 20 year old chillers, and REDUCING the capacity as the a) use has changed, b) more efficient chillers going in, c) over 50% reduction in load spread over 3 chillers.
As to your question, if it's an open motor ... they can be rewound. If they are sealed ... contact Carrier.

 

[sailoday28]

I'm told that the replacement compressor is per the original design. Are you stating that we have to live with it or can get a more efficient compreesor?

 

[cturg]

What is the 38AE044570? 40 ton condensing unit? Would that have a Carlyle semi-hermetic compressor(sealed-motor)? Not worth the expense retro-fitting another style compressor in there. Go back with the OEM compressor, identify and repair what took it out.

 

[ElSid1]

sailoday28,
I am saying you should look at the options. As an engineer, you are tasked with making an educated decision, part of which is an economic evaluation. IF, the unit cannot easily be replaced or an economic payback takes too long, then your options are limited and you re-place. Technology, controls, and the use of the space has changed. Evaluate and recommend. How old is the unit? What made it fail? Lots of open questions ...

cturg,
In my case, the chillers were old, the system in the space had been re-vamped, the space was retrofitted with different coils and controls and the analysis showed that that a (read one) chiller was being used at 40% at peak load with the other units short circuting themselves. Evaluate what you have. It comes down to the owner having to live with the unit say for 20 years. If the payback in efficiency and modernization is there, it should be looked at. This falls in line with the use of VFD's. For many years, they were magical black boxes that no one wanted to pay for ... now almost all retrofits or new installs use them as cost savings. Look at your AC compressor at home. If it's at least 10 years old, it's probably a 10 SEER or less compared to 16 to 20 SEER compressors sold today. I can show a payback in 5 years or less with those numbers ... with a new warranty. The client should have the options infront of them.

 

[317069]

Call Carrier