# Finding formula for Kilowatt too BTU?

Originally Posted By: Kevin Blackwell
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I am searching for the formula to calculate the btu’s need-it if you have the (kw) and square footage.

For example if you have 6.5kw and 2800' sq.ft property,
How do you figure out the BTU's need-it.
Thx Kevin from Houston,TX

Originally Posted By: cbottger
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The BTU is normally on the Condensing unit within the Model # 36 would =

36000 BTU. 12000 BTU = one ton of cooling. A rough estimate before any building heat load is calculated would be 500 sq Ft of living space per ton of A/C Depending on what contractor you talk to sq. footage can and does range from 400 to 700 sq ft per ton of cooling

Don’t argue with an idiot someone watching may not be able to tell the difference.

Originally Posted By: Blaine Wiley
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You figure out the BTU’s by multiplying each kw by 3412. Hence a 5 kw electric furnace will have 17,060 BTU. Then follow Charlie’s formula.

Originally Posted By: afernbaugh
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If I understand the question you are asking you want to know about the relationship between kilowatt hours, BTU and square footage of heated and cooled area.

As Kevin and Blaine have both given you some good information I will try to lace it up in neat package for you. Down here, in the deep south,(this may vary with climate) a 2000 sq. ft. home would require 4 tons of air conditioning to keep the interior near 72 degrees F during cooling season and about double that BTU number for heating. The basis for this is that a “normal” cooling day at peak season is at 92 degrees F in my area. During heating season most HVAC contractors use 32 degrees F ambient temperature as their sizing assumption; heating to an interior temperature of 72 degrees F. The delta temperature for cooling is 20 degrees F and the delta temperature for heating is 40 degrees F; therefore the 2 to 1 ratio and a doubling of the btu rating for heaters vs. cooling.

As Blaine has said a 5 kw strip will produce about 17,000 btu. Accordingly, this 2000 sq. ft. home (above) would need about six (6) 5kw strips to produce 100,000 btu.

I hope this helps you.
Regards,
As Blaine explained you need to calculate the number of heating strip elements required

--
Alan Fernbaugh
Five Star Inspection Services
Baton Rouge, La.

Originally Posted By: Blaine Wiley
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I did leave out the part about doubling the cooling for heating didn’t I? Thank you Alan!