Author Topic: Ice to Water - BTU Calculation  (Read 803 times)

Offline Admin

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Ice to Water - BTU Calculation
« on: September 29, 2017, 09:27:35 AM »
Someone messaged me with a question and I'm not sure why my answer is different.  Does anyone know?

Quote
I need your help to solve this equation.
How much heat is required to raise the temperature of 100lbs of water from 10F to 120F?
Answer: 24,300 btuh

It looks like we first have to melt 100 pounds of ice into water.  It takes 144 BTU's to melt 1 pound of ice into 32F water.  So 100 pounds of ice x 144 BTU's = 14,400 BTU's.

Now we take 120F - 32F = 88F.  This is how many degrees we need to heat the water from 32F to get to 120F.

88F x 100 pounds = 8800 BTU's.

8800 BTU's + 14,400 BTU's = 23,200 BTU's.

It's close to the answer you have.  I'm not sure why my answer is different though.

Offline Porcupinepuffer

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Re: Ice to Water - BTU Calculation
« Reply #1 on: September 29, 2017, 11:51:39 AM »
You missed the 22 degrees of sensible heat to bring the ice from 10 degrees to 32 degrees.