How much fuel does my Swimming Pool Heater use

Propane heaters use one gallon of fuel per hour for each 91,000 BTU's of heater input.

Example: A 250,000 BTU heater uses: 250,000/91,000 = 2.75 gallon per hour.

Natural gas heaters use one therm (100,000) BTU per 100,000 BTU's heater size. Your gas is usually billed by therms.
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