Hi PPl.. Im a newbie to this forum and new to HVAC. I need some advice from the expert here on some RT confusion.

To find AHU cooling Ton:

Formula 1.
RT = M x C x Delta T
RT = 500 x l/s chilled water flow rate x DT in deg c
RT = 500 x 9 x (12-6) deg
RT = 27,000 BTU
RT = 2.225RT

Formula 2.
RT = flowrate x 1.186 x Delta T
RT = 9 x 1.186 x (12-6)deg c
RT = 64RT

What have i missed out?

Thank you very much.