Free pool heater BTU calculator for estimating the heater output needed to raise pool water to a target temperature in a chosen time.
Estimate pool-heater output for a warm-up period. Enter pool dimensions, temperature rise, recovery time, and heater efficiency. This warm-up estimate does not include ongoing wind, evaporation, cover, or ambient heat loss.
BTU/h is the heat energy delivered per hour. A larger pool, greater temperature rise, shorter warm-up time, or lower efficiency increases the estimate.
No. Wind, evaporation, outdoor temperature, and whether the pool is covered can require extra heater capacity.
Average depth gives a better estimate of water volume than using only the shallow or deep end.