Size steam coil
Need to size a water tank heating coil to prevent icing. I evaluated the heat load of the tank and get the heat transfer coefficient between pipe and water. One question is how to get the temperature difference: ambient is -40degF, water is to maintain 32-35degF and steam temperature after control valve is 400degF. Is it right just to assume steam temperature constant and use (400-35)degF as deltT ? The area calculate in this way is fairly small.
Another question is to get the outlet steam/condensate parameter. I use 2" pipe and has the steam property 250psi and 400degF after control valve. I do not know outlet steam parameters and can not calculate the steam flow rate required.
Please clarify me and if knowledge of code or book on this issue, please let me know.
--It boils down to simple math--