Condensing Gas Water Heaters

A Condensing Gas Water Heater is an appliance that provides a constant supply of hot water at a preset temperature.

Condensing Gas Water Heaters


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How It Works

Condensing gas water heaters work very similar to conventional gas water heaters. The makeup is straightforward - a large, insulated tank of water is heated by a gas burner. Where a condensing gas water heater is different is instead of exhausting the combustion gases, those gases are captured and utilized to heat the water more efficiently.

As seen in the diagram, a conventional gas storage water heater has its flue running straight up through the middle that exits from the top. A condensing gas water heater has its flue designed with greater surface area so the heat and combustion gases have much farther to travel before they exit the water tank. The result is more heat transferred to the water in the tank.


You will want to consult your installer to determine the ideal size of the tank and the proper maintenance guidelines. To ensure that you select the right size tank, check the capacity and first-hour rating. The first-hour rating indicates how much water the unit can deliver during a busy hour.

Service provider maintenance programs are usually available as well if no one on site is trained to maintain the water heater.


  • Energy and cost savings, leading to less operating costs
  • Less water usage leads to a better environment
  • A constant supply of hot water

Building Applications

Condensing gas water heaters are the best choice for commercial buildings because they cost less to operate and deliver more hot water under high demand in less time than electric heaters.

Industry has long understood that natural gas is the fuel of choice when it comes to heating water, which includes restaurant, laundry, health club, healthcare, hotel and apartment operators.

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