This calculator allows you to convert from Foot water (4°C) to Pound-force/square inch and in a reverse direction. To convert from Foot water (4°C) to Pound-force/square inch, enter the amount of Foot water (4°C) into the first input and to convert from Pound-force/square inch to Foot water (4°C), enter the amount of Pound-force/square inch into the second input.