Gas pool heaters use natural gas or propane to heat your swimming pool and maintain a constant temperature you desire. This is the greatest advantage of gas heaters, since they don’t rely on outside weather sources to heat your pool and keep it warm. On average, gas pool heaters usually generate more BTUs (British Thermal Units) an hour than heaters that rely on the outside environment. This means your pool will be heated much more quickly when compared to other heating methods.The gas swimming pool heaters at Pool Express are available in liquid propane models and natural gas models. If you want to buy a natural gas pool heater, don’t forget to consider the fuel prices and availability in your area. Today, many gas heaters are available in low-nitrogen oxide models, which mean they are designed to produce fewer emissions than traditional heaters. Low NOx heaters are an environmentally friendly alternative to traditional heating methods of the past.