When looking for the best gas water heater, one of the most important things to consider is its operating costs. Gas water heaters are generally cheaper to run than electrical units, because of the lower price of gas. However, this economical advantage is somewhat offset by the lower efficiency of gas models. For example, traditional gas storage water heaters only have an efficiency of about 58% compared the 95% efficiency of electric tank water heaters.
Recently, however, due to rising energy costs and increasing awareness of global warming, gas water heater manufacturers have focused their attention on improving efficiency. This has resulted in the proliferation of tankless gas water heaters with an efficiency of about 82% or 83%. There has also been strong competition in the industry to produce the best tank models. This has been encouraged by the US Department of Energy’s recent Energy Star tax incentive, which offers a 30% tax credit on purchases of gas storage tank water heaters with an energy factor (EF) of 0.62 or higher. This is equivalent to an efficiency of about 63%.
To achieve this higher efficiency, manufacturers of storage water heaters have added insulation to reduce standby heat losses through the wall of the tank. They have also added heat traps, and have developed more efficient burners. In some models, the energy wasting pilot light has been replaced by an electronic ignition system, and the water heaters life expectancy has been increased by coating the inside of the tank with glass.
Gas water heater reviews indicate that in a consumer research poll of 300 plumbing contactors, that most contractors voted the Bradford White “Defender Safety Series” as the best high efficiency gas storage water heaters. There are 5 models in this series, with capacities ranging from 30 to 60 gallons. The 40 and 50 gallon models sell for about $400 to $500, and these units are eligible for the 30% Energy Star tax credit, which also includes installation costs. Rheem’s “Imperial Gas Series” are also excellent high efficiency water heaters. The AO Smith high efficiency water heaters should also be considered.
Tankless water heaters (also known as “on demand” water heaters or “instant hot water heaters”) can provide an unlimited amount of hot water whenever you need it. They are also very small and can easily be mounted on a wall. Besides their 20% efficiency advantage over even the high efficiency tank units, tankless gas water heaters also last at least 5-10 years longer. They are generally more expensive than tank water heaters, but your water heating bills will be lower, and with these savings, and your 30% tankless water heater tax credit, you should be able to make up the difference in price in just a few years. The best gas tankless water heater models are manufactured by Noritz, Takagi, Bosch, Rheem, Rinnai and Paloma. All of these manufacturers make residential and commercial models. Noritz makes very high quality water heaters, and their 0931 Series models are the highest capacity on demand water heaters on the market. Their commercial models are ASME certified and the heat exchangers in all their models are commercial grade. Their Dual Flame Burner Technology results in more precisely regulated hot water temperatures than other brands. Noritz tankless gas water heater models vary in price from about $600 to $1,900.
The very best gas water heaters are condensing water heaters. This recent development in gas water heating technology, has improved the efficiency of both tank-style and tankless gas water heaters to above 95% in some cases.
Condensing water heaters achieve this high efficiency, by utilizing the heat that is normally lost in the exhaust gases that escape through the flue. Condensing water heaters have a second heat exchanger through which the exhaust gases pass. As they do so, they condense, adding their heat to the water.
The cheapest tank-type condensing water heaters are the two Vertex models made by AO Smith. The Vertex GDHE 50 is a 50 gallon direct vent model. It sells for about $1,600 to $1,700. The Vertex GPHE 50 is a power vent model. It sells for about $2,100 to $2,200. The hot water output of these 50 gallon models actually exceeds that of a 75 gallon water heater. These water heaters can replace your old style tank models without any upgrades to your gas lines or venting system.
Other tank–style condensing water heaters with an energy efficiency above 90%, are the Phoenix models (Heat Transfer Products) and the Polaris Series (American Water Heaters).
If you add the advantages of tankless water heaters to the efficiency advantages of the condensing water heater technology, you have a water heater that is not only the best gas water heater, but also one of the very best water heaters of all types.
The best tankless gas condensing water heater is made by Navien America. The Navien Tankless Water Heater models have an astounding 98% efficiency. These models not only have many highly advanced features, but they are also very eco friendly.
If you are thinking of replacing your old tank water heater with a tankless condensing water heater like one of the Navien models, you will need to upgrade your gas lines to ¾ inch. The cost of the upgrade can, however, be offset by the 30% Energy Star tax credit.
Other tankless condensing water heaters with an efficiency of over 90%, are the Noritz N-0842MC, the Bosch GWHC 920ES/ESC and the Takagi Flash T-Hi.