Along with your inquiry please specify -

Name of the fluid to be heated or cooled
Flow rate per hour and working pressure of the process fluid
Intel & desired outlet temperature of the process fluid
Temperature of cooling water available for cooling or pressure of steam available for heating, whichever applicable.
Heat to be dissipated in kcal/hr
Capacity in cfm of air incase of Compressor
HP/KW rating incase of Hydraulic Power Pake/D.G. Set/Furnace
Change Quenched in kg/hr incase of heat treatment process
The size of the existing Heat Exchanger incase of a replacement giving no. of tubes, OD & length of tubes,body diameter, passes etc.