Hi All,

I don't mean to ask questions back to back days here, but I ran into roadblock. I found an equation for the compressor EIR to be:

Cooing EIR=(1/EER-0.012167)/(1/3.413-0.012167)

Has anyone tried to derive this, or know of a document that has done so? I seem to be missing something in my derivation as follows:

* EER=Cooling Output (Btuh)/(Supply Fan Input (W) + Compressor Input (W))

* 1/EER=Supply Fan Input/Cooling Output + Compressor Input/Cooling Output

* Compressor Input/Cooling Output = 1/EER - Supply Fan Input/Cooling Output

At ARI condition supply fan is rated at 365W/CFM & 400CFM/Ton
So Supply Fan Input/Cooling Output = 0.146 kW/Ton or .012167 W/Btuh

* Compressor Input/Cooling Output = 1/EER - 0.012167

* Compressor Input/Cooling Output (Btu/Btu) = 3.413*(1/EER - 0.012167)

i.e.

EER=11
Compressor EIR = 3.413*(1/11 - 0.012167) = 0.2687 (should be 0.2580)

Is there something that I am missing?

Thank in advance,

Daniel Kaler