The Top 10 Swimming-Pool Heaters

Rheem Raypak R8350ti-E-HC

• Rheem's top-of-the-line electric heat pump pool heater got the highest ratings for energy efficiency from a study performed by the Brookhaven National Laboratory. At around $4,400 before installation, this heater is one of the more expensive electric models. The heater was able to keep 18,000 gallons of water at a steady 82 degrees in 65-degree ambient weather.

Jandy Hi-E2 Swimming Pool and Spa Heater

• At over $6,000 retail, the Jandy Hi-E2 is one of the most expensive residential pool heaters on the market. This natural gas heater is capable of heating your 20,000-gallon pool to 85 degrees in 45-degree ambient temperature within three hours.

Hayward HeatPro 50TA

• The Hayward HeatPro titanium pool heater starts at only $1,700 and received a score of 84 percent energy efficiency from Brookhaven National Laboratory's study. This electric heater features a digital display that allows you to operate your heater by either timer or water temperature.

Hayward Universal H-Series

• The Hayward Universal H-Series is Amazon.com's best selling pool heater. Available in either natural gas or propane models, these heaters start at just $1,200. They come with two-year warranties and feature low emissions.

Lochinvar EnergyRite Natural Gas and Propane Pool and Spa Heater

• Starting at around $2,600, the Lochinvar boasts the fastest heat-up time in the industry. This means that you can save money by turning the heater on only when you plan to swim. The EnergyRite model also features thermal efficiencies up to 88 percent.

AquaPro In-Ground Pro Series Heat Pumps

• The AquaPro Pro Series is the only heater on the market that comes with a 15-year warranty. This line of commercial grade heat pumps starts at $3,000 and features the environmentally-friendly EcoAPEX design. The AquaPro works in ambient temperatures as low as 38 degrees.

Jandy LXi Low NOx Pool and Spa Heater

• The LXi Low NOx is Jandy's eco-friendly natural gas or propane pool heater. This heater offers up to 88 percent thermal efficiency and comes equipped with a digital control system that allows you to program your heater to turn on only when the water temperature drops.

Solar Arc Swimming Pool Heater

• Perfect for environmentally-conscious pool owners on a budget, the Solar Arc heater starts at only $300 and does not require a professional installation. These heaters cost nothing to operate and have no emissions. They can also be moved around to the sunniest spots in your yard throughout the day.

Heliocol Solar Heating System

• The Heliocol Solar Heating System for residential pools requires a professional installation and you need to make an appointment with a dealer for a quote. This rooftop system comes with a 12-year warranty and Heliocol panels can raise the temperature of your water by up to 15 degrees, depending upon the system you choose.

Solar Sun Rings Solar Pool Heater

• Solar Sun Rings are designed for pool owners who want to keep their pools warm but don't want to invest in permanent heaters. These rings are available for about $25 per ring, and they're designed to blanket the surface of your pool in order to retain heat.