Steam required by a coil calculator

Divide the useful heating load by usable enthalpy drop and coil efficiency.

Units

\dot{m} = \frac{q_{\text{water}}}{\eta_{\text{coil}} \times \left(h_{\text{in}} - h_{\text{out}}\right)}

Calculator

Enter the values you know and leave one box empty. Calculate finds the empty one, the result or any input.

Given

\dot{m} = \frac{240{,}000}{0.88 \times \left(1180 - 170\right)} \approx 270

Symbol	Meaning	Unit
$\dot{m}$	required steam mass flow	lb/h
$q_{\text{water}}$	useful water-heating rate	Btu/h
$\eta_{\text{coil}}$	coil heat-transfer efficiency	—
$h_{\text{in}}$	steam inlet enthalpy	Btu/lb
$h_{\text{out}}$	actual outlet-condensate enthalpy	Btu/lb

Symbol	Meaning	Unit
$\dot{m}$	required steam mass flow	kg/h
$q_{\text{water}}$	useful water-heating rate	kW
$\eta_{\text{coil}}$	coil heat-transfer efficiency	—
$h_{\text{in}}$	steam inlet enthalpy	kJ/kg
$h_{\text{out}}$	actual outlet-condensate enthalpy	kJ/kg

Results are estimates for study and screening. Check the inputs, units and assumptions before you use them for design, billing or contract decisions.