Condensation Problems in Your Boiler?

 Boiler Tip Archives
 Jan 09 - Return Temps
 Oct 07 - Condensation
 
Condensation is a thermodynamic process whereby moist gasses condense on a surface that is below the dew point temperature.

That is true of the windows on your dwelling and it's true in boilers as well. In your house, you’ve noticed that the colder the outside
temperature is, the more condensation you get on the windows. When the temperature is hot outdoors, there is no condensation on the windows. The same phenomenon is true for equipment that contains products of combustion. Surfaces with a temperature above the dew point cannot have condensation on them.

With that said, can the dewpoint temperature of products of combustion be found? Sure, that is covered in first year thermodynamics at any Mechanical Engineering school.

What is hard to determine is how there can be condensation in boiler. Every water boiler manufacturer lists what the minimum return water temperature. The reason is fairly obvious because the colder the water temperature, the colder the boiler tubes will become. In boilers, when the tube temperature becomes at or below the dew point temperature, there will be condensation. As moisture increases, the hot surface igniters and flame sensors get wet and fail far too often creating an emergency situation that needs to be resolved.

If the set point temperature in a hot water boiler is too low, say 120°F, then the exit temperature of the gas may be cooled to below the dew point. Burner turndown has nothing to do with this, only the gas temperature versus the dew point temperature.

The Benrich Service Company has been a leader in innovations that improve the function and reliability relating to commercial domestic hot water systems. Their latest effort has been specifically directed at the continued failures of mid-efficiency (85%) water heating boilers.

Commercial domestic hot water systems are required to deliver hot water temperatures to the end user, that are both safe from scalding and at the same time reliable during peak usage. The challenge with these boilers is that internal water temperatures can fall below 123° which can cause condensation, which in turn creates a wet environment within the combustion chamber.

When considering the health and comfort of the end user and the overall efficiency of the system, the desire is to maintain safe output temperatures and increase reliability.

This can be accomplished in a simple, cost effective manner by installing a thermostatic bypass valve on the boiler that is preset to maintain a 135° temperature within the combustion chamber of the boiler. This effectively eliminates condensation, and improves reliability.

For more information on this technology and its benefits, feel free to contact Skip Baker at Benrich Service Company (714) 241-0284
EDC Technologies, Inc. 708 Gravenstein Hwy. N. #56, Sebastopol, CA 95472
888.346.8426 ph - 925-848-3290 fx
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