Energy Guide

Calculate the pool surface area in square feet.
Use the following formula to determine the Btu/hour output requirement of the heater:
Pool Area x Temperature Rise x 12
This formula is based on 1º to 1-1/4ºF temperature rise per hour and a 3-1/2 mile per hour
average wind at the pool surface. For a 1-1/2ºF rise multiply by 1.5. For a 2ºF rise multiply by 2.0.
Determining Efficiency of a Gas Pool Heater
New gas swimming pool heaters have a standard test they go through to determine their energy
efficiency based on their Btu (British thermal unit) output.
Heater efficiency is the ratio of usable output to energy input. For example, an 80%-efficient
heater uses $80 worth of useful heat for every $100 worth of fuel. Therefore, it wastes 20% of the
fuel.
Most gas pool heaters feature their efficiency percentage on their nameplates. A pool heater's
manufacturer can also provide its efficiency percentage.
Today, you'll find some gas pool heaters with 89%–95% efficiency. The following table shows
how much you can save for every $1,000 in annual pool heating costs by installing a gas pool
heater that's 95% efficient.
Table 1. Costs of Outdoor Pool Gas Heating by Location*
Location
Season
Temperature
78°
80°
82°
Miami
1/1–12/31
$2136
$2848
$3600
w/cover
1/1–12/31
$416
$584
$800
Phoenix
3/1–10/31
$1384
$1776
$2216
w/ cover
3/1–10/31
$96
$168
$256
Dallas
4/1–10/31
$1512
$1920
$2456
w/ cover
4/1–10/31
$184
$280
$408
Atlanta
4/1–10/31
$1704
$2248
$2880
w/ cover
4/1–10/31
$320
$424
$592
Los Angeles
5/1–10/31
$1864
$2376
$2904
w/ cover
5/1–10/31
$168
$304
$472
Kansas City
5/1–10/31
$1434
$1872
$2384
w/ cover
5/1–10/31
$288
$416
$544
New York
5/1–9/30
$1448
$1904
$2384
w/ cover
5/1–9/30
$208
$296
$400
Chicago
5/1–9/30
$1621
$2072
$2536
w/ cover
5/1–9/30
$216
$296
$384
Denver
5/1–8/31
$1757
$2120
$2498
w/ cover
5/1–8/31
$123
$168
$243
Boston
5/1–8/31
$1712
$2096
$2504
w/ cover
5/1–8/31
$232
$328
$461
Minneapolis
6/1–9/30
$1331
$1776
$2176
w/ cover
6/1–9/30
$192
$248
$384
San Francisco
6/1–8/31
$1560
$1856
$2168