This calculator allows you to convert from Btu (th)/second to Kilocalorie (IT)/hour and in a reverse direction. To convert from Btu (th)/second to Kilocalorie (IT)/hour, enter the amount of Btu (th)/second into the first input and to convert from Kilocalorie (IT)/hour to Btu (th)/second, enter the amount of Kilocalorie (IT)/hour into the second input.