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Challenger Combination Boiler’s Copper Heat Exchanger Pulls Double Duty

April 6, 2015

The new Challenger Combination Boiler features a unique copper heat exchanger that is as simple as it is efficient.  With a 96% AFUE rating in space heating mode, the Challenger is an efficiency leader.  But the Challenger’s unique heat exchanger is extremely efficient in domestic water heating mode as well.The Challenger’s heat exchanger features two copper waterways that heat both the space heating and domestic water.  Nearly all other combination boilers heat domestic water in a seperate, secondary heat exchanger.  This results in additional components and reduced efficiency.

What is a Condensing Boiler and Why is it Efficient?
The Challenger is a Condensing Boiler, which means that it condenses the moisture in the flue gases from combustion.  When it condenses this moisture, it pulls more heat from the flue gas into the heat exchanger.  We all have seen how a glass of cold water condenses the moisture from humid air.  The cold water absorbs heat from the air to allow the moisture to condense?

In the opposite mode, we have all seen how heating a pot of water will cause some of the water to evaporate into steam.  If you think about this process, you can add heat to water to bring it to the point of evaporation.  But if you stopped adding heat at this point the water would not evaporate.  But if you add heat, the water will use this heat to make steam.  This heat is called latent heat.  When a condensing boiler condenses, it is removing this latent heat from the steam.

Challenger gains Condensing Efficiency in Hot Water Mode

Challenger Combination BoilerWhen the Challenger heats the domestic hot water that is used in showers, laundry, dishwahers, and sinks throughout the house it is working at peak efficiency.  The cold water entering the boiler gives the heat exchanger the opportunity to maximimize the latent heat it can extract from the flue gas.

Other combination boilers are not able to gain this latent heat as they do not run the cold domestic water into the primary heat exchanger.  They run boiler system water to a secondary heat exchanger to heat the domestic hot water.  This boiler system water does not return to the primary heat exchanger at a low enough temperature to condense.  Therefore other boilers are not able to gain the efficiency of the Challenger.

Jim Lavallee Plumbing
Serving Eastern Massachusetts and the Boston area
Phone: Toll-free (888) 884-4122

(original article)

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