Condensing Boilers 250px

Condensing Boilers

MPN Boilers specializes in- hot water condensing boilers with sizes ranging from 300,000 BTU/HR. to 12.0 MM BTU/HR. (300HP). The boilers can be high mass or low mass pressure vessels to suit any new or replacement projects.

Condensing boilers are a tool in the fight to reduce energy consumption and operating expenses.  Condensing boilers have been shown to reduce energy consumption by up to 60% in properly designed systems and building conversions.

Please let us know if you would like a copy of a study from the Mid-West detailing these conversions and the results.


Like any other piece of equipment, condensing boilers must be applied correctly, or many of their benefits will be lost. The most important consideration is water temperature.

Condensing boilers fire natural gas or propane. When natural gas burns, water vapor is formed. If this water vapor can be condensed inside the boiler; a significant amount of energy can be recovered. Normally, this energy just goes up the stack and is lost.

Since the dew point of typical natural gas combustion products is about 140°F, this requires that some part of the boiler be at a temperature somewhat cooler than 140°. European hydronic systems operate at relatively low temperatures and can return water to the boiler at temperatures of 100°F to 120°F.

Since we are so used to the “American” standard of 180°F supply to the system and 160°F return to the boilers, we need to change our thinking to get any extra efficiency boost out of a condensing boiler. Operating at these water temperatures, there is no way to condense natural gas combustion products. The efficiency of the boiler will be no higher (and in some cases actually lower) than the efficiency of a more conventional hot water boiler.



Another aspect of condensing boilers is that they are most efficient at low loads. The wet combustion products have more time in the boiler to condense. This means that in multiple boiler installations, we want as many boilers operating as possible without exceeding the demand for heat.

At MPN, we offer a broad selection of condensing boilers; including the Cleaver Brooks ClearFire family and Raypak’s XTherm & XFyre.

Please call or e-mail us for more information about any of our products. We welcome the opportunity to work with you to help your clients reduce their energy costs while protecting the environment