Input yellow fields and tab through for results!

Costs listed above are Posted Retail Costs! Free Hot Water sells only to distributors and contractors.


Enter any flat-plate collector BTU and sq. ft. - Default collector listed above is the 4x10 - 8000 series:

• (FHW 7000 Series, 28,400 BTU, 27.67 Sq. ft.)
• (FHW 8000 Series, 42,400 Btu's, 40 sq. ft.)
• (FHW 5000 Series, 23,100 BTU's, 22.28 sq. ft.)
• (FHW 4000 Series, 21,500 BTU's, 21.86 sq. ft.)
Please contact us with any questions. If you would like this calculatior on your site, just ask and we'll help you with the code.

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