# Btu/lbm to change water to vapor



## dpolet (Jul 18, 2013)

NCEES 2008 AM #138 use 970btu/lbm. However, I found at 14.7psia, the water Hfg=1060 btu/lbm. They have different btu/lbm, did I miss anything? Thanks.


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## CRNewsom (Jul 19, 2013)

My tables list hfg of water at 14.696 psia at 970.4 Btu/lb.

The only values I see where hfg approaches 1060 Btu/lb is at 0 psia. Perhaps your reference tables have psia and psig confused?


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## dpolet (Jul 20, 2013)

CRNewsom,you are correct. I mixed psia and psig. Thank you.


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