HVAC - views about CFC refregerent Vs. eco friendly refrigerent

[tejalr]

Hi

We are planning the HVAC for our new office site 80KSF. I would like your viewss on

Reciprocating Vs. Screw

Has anyone carried out any analysis between Recip and Screw to check the energy savings
What is your views about CFC refregerent Vs. eco friendly refrigerent.
What are the key 3 to 5 parameters in your opinion to be evaluated / addressed

Your views about various brands such as Trane, Carrier, Bluestar, Danhum Bush

Any other that you feel most important

 

[quark]

As far as chiller types are concerned, I would prefer the following range.

Upto 100 TR - Recips
100 - 300 TR - Screws
300 TR and above - Centrifugals

Basically centrifugals are the best at part load efficiencies and capacity control is superior. Unlike Recips, screws have step less control.

Some points to check are
1. Part load efficiency
2. Specific power consumption (at various loads)
3. Ease of maintenance
4. Availability of services and spares

A simple fact about refrigerants

One chlorine atom breaks ozone and converts it to oxygen for 180 years before it disintegrates. Rest is your choice.

Don't forget to add York to your list.

Best Regards,

 

[VSSriram]

I believe one more decision needs to be taken in choosing the right system - i.e. air-cooled or water-cooled. I presume tejalr is from India, since he has referred the name "Bluestar". There are many places where availability and hence cost of water is very high and air-cooled chiller may work out economical. In fact, in some places, local legislation may not allow water to be used for cooling tower purposes !!!

Choice of system should also depend on the total capacity requirement, type of application, part load requirements, redundancy, etc.

Carrier has an excellent software program to do an analysis on the right type of system.

On a generic basis, I agree with quark. However, depending on various factors like load pattern, etc., one could opt for a combination of centrifugal and screw as well. Contact a Carrier guy - he can probably help out as well.

Regards

Sriram

 

[kjwalt]

Realize that many HFC's have a disadvantage over HCFC's when it comes to the refrigeration cycle efficiency. This means that you are requiring more energy to be generated thus increasing the release of CO2, SO2, and NOX into the atmosphere. These have a significant effect on global warming and ozone depletion. One other thing to realize is that you shouldn't only be looking at ozone depletion. Global warming potential may be becoming a bigger deal than the ozone depletion.