Cheaper - Evap Makeup Air Units or DX packaged units?

[John_187]

Hello,

As a general rule, what is considered cheaper for material cost - evaporative make up air units or DX packaged rooftop type units? Assume this is a dry climate where evaporative cooling is effective. Both units have indirect gas heat exchangers. Both units should provide the same cooling effect to the space (which is a high ceiling warehouse type of space).

In order to provide the same cooling effect to the space, it is assumed the evap cooler must provide about 50 % more airflow than the DX cooling unit.

Thanks for any insight

 

[chicopee]

"Assume this is a dry climate where evaporative cooling is effective" Never assume anything for real world situations. My now deceased thermodynamics teacher whose practical experiences were in a major chemical manufacturing company in our locality wrote on my test paper " Assume makes an Ass out of U and Me" even thought my assumption in that test was correct but a test does not represent real world situations.