According to these guys (www.42u.com): CRAC vs. CRAH Though they serve the same purpose, there is a fundamental difference between a CRAC and CRAH: A Computer Room Air Conditioner includes an internal compressor, using the direct expansion of refrigerant to remove heat from the data center. A Computer Room Air Handler includes only fans and a cooling coil, often using chilled water to remove heat from the data center.
The vast majority of people I've ever spoken with about data centers use the term CRAC instead of CRAH. As a matter of fact, when it comes to CRAC versus CRAH, I would always use the term CRAC, because when you say CRAH (pronounced CRAY), most people will not know what you mean... and yes, these are data center/IT gurus!