To figure out the size of pool heater you require, consider the shape and size of your pool and the temperature you want it to be. In addition, consider how powerful you want the pool heater to be.
The size and shape of your pool dictates the size of heater you need. To calculate the size of your pool, simply multiply its width, length and depth, and round off your measurement to the nearest feet. Multiply your pool's cubic feet by 7.5 to calculate the number of gallons that need heating. The larger the surface area, the more thermal units the heater must turn out.
Next, consider what temperature the pool should be. Consider your climate during different seasons, and determine how much heat the pool's surface loses during winter or at night. Finally, consider how powerful you want your pool heater to be. More powerful pool heaters are generally more efficient. The law requires all pool heaters to operate at a minimum thermal efficiency of 78 percent. The more efficient your pool heater, the less energy it uses and the less costly it is to maintain. Finally, conduct research on the quality of various pool heater brands before purchasing one.