View Full Version : Eer

28-12-2010, 09:36 AM
Dear All,

I'd like to know the proper method of calculating EER for package units. From what I know, the formula is cooling capacity(Btu/hr)/Power input in watts but what cooling capacity should be taken, nominal or total. The reason I'm asking this is that I have problem comparing units of different brand since some of the suppliers are not suppling nominal capacity data. Thus I cannot compare apple for an apple. Please advice how I should go about this.
Also, if some supplier claims to be supplying units with EER more than 10.0, what certification must the supplier have to back this??

Thank you

28-12-2010, 10:45 AM
Same thread posted yesterday with the same title.
EER is a self-declaration and can't be backed up.
You may ask the supplier to provide the compressor selection sheet at the rated condition.
Anyway, EER is better expressed kW/kW than BTU/kW, because being EER a pure number, the fraction should be made of compatible units of measurement.
kW is a metric unit, BTU/h is Imperial.
Therefore BTU/h / kW is deprecated.

29-12-2010, 07:47 AM
thanx alot for the prompt reply....but my concern is that our supplier that claims to be supplying EER more than 10 is way more expensive than others....but the problem is their catalogue does not support their declaration...according to the information provided in the catalogue, they do not meet the EER they claim to be meeting. For the same models however, the slection data sheet presents values that bring the EER up to 10.5. Which document should I be trusting, the catalogue or the selection data sheet??

29-12-2010, 09:59 AM
Selection and catalogue, provided the working conditions are the same, should provide the same data.

29-12-2010, 10:11 AM
thats exactly my point, it should provide the same data with same working conditions but they are actually providing different data claiming that those units are high effeciency units with EER more than 10.0. I think catalogue should be treated as an authentic data source here. what do you think? Thanks

29-12-2010, 11:03 AM
Of course. Data sheet is a more detailed data report, that nonetheless should be compliant to catalogue.

01-01-2011, 10:08 AM
Well that doesn't appear to be the case but I guess, its catalogue that we have to take as authentic...........Anyway, if you have any idea, what exactly are the changes in terms of engineering made inside the unit that makes it high effeciency.......are these changes costly??? what should be the end price difference in percentage terms between a standard and high effeciency unit with similar specs....Thank you

01-01-2011, 10:21 AM
From nothing to anything. Ask them, and if they come up with any reasonable explanation of the differences we can discuss it here.