Boilers On Demand

Developers of the "Neo-Gravity Hydronic (FHW) Heating Appliance (TM)" - U.S. Patent 10,690,356, Canada Filing 2,964,131. Our Industry-First Appliance is simply positioned, piped and powered, comprising over 95% the content of a typical hydronic heating replacement installation! Emulating Mother Nature we optimize natural gravity convection by integrating a hard-piped, Commercial-rated Weil-McLain UO Boiler with Taco Delta-T Distribution. Our multi-fuel optioned Appliance has a predictable service life of well over thirty (30) years, typically twice the minimum of contemporaries. Our "Betas" (test sites) have currently aggregated over fifty (50) operating-years and 150,000 hours on our Beta-Sites with no system-related service calls ..... none! We confidently challenge any hydronic engineer, tradesman or installer to match or exceed its documented performance! "Simple, Durable, Efficient Hot Water Heating ..... Period!"


New and existing Weil-McLain Oil Boiler Installation & Service throughout NH. (65 year history) Now, as a Heating Appliance MANUFACTURER we supply, install, train & assist within the Northern U.S. and Canada as Local Codes may permit. Future licensing inquiries are also welcomed.

Case Study: The "Neo-Gravity Hydronic (FHW) Heating Appliance (TM)"


Replace the contemporary "build-on-site" kitting method of hydronic heating installations with an application-specific hydronic heating appliance. Current practices are materials and labor inefficient and provide inconsistent results. A "designed-for-manufacture" integrated appliance is the logical, technical progression.


Having physically participated in the heating industry for over sixty-five (65) years, little has changed beyond the developmental progression of individual hydronic components. There is no "blueprint" for process optimization beyond the typical Boiler Manual Piping Diagram as a guideline. This does not comprise a hydronic process by any measure! The heating industry has discarded innately favorable hydronic attributes such as natural (gravity) convection, opting instead to develop artificial system algorithms. Applying a fifty (50) year Manufacturing Process Engineering career and basic physics (biomimicry) to hydronics has provided a natural and technically sound PROCESS solution.


Of the three (3) basic hydronic heating elements, heat generation (boiler), distribution (pipes & pumps) and radiation (heat conversion), distribution is the least understood nor appreciated. We cynically refer to contemporary distribution practices as "The Plumber's Playground", contributing no quantifiable economic or process value to system operation or performance. The development of Delta-T Hydronic Distribution has forever changed hydronics. Forty-five (45) years ago we began experimenting with gravity convection on our personal multi-fuel heating system and much further a decade ago by applying delta-t circulators. Thanks to Taco Comfort Solutions providing technical and material assistance we have amalgamated delta-t with natural convection to "put an 'automatic transmission' on a boiler", as we say. Our Ten (10) monitored Beta Sites have now aggregated over fifty (50) years and 150,000 hours of operation, all using 8 to 13 Watts of total distribution energy in a variety of applications with NO system-related service calls ..... NONE!

Boilers On Demand

5 High Street
Antrim, NH 03440

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Paul D. Mercier, Sr.
Phone 603-588-2333
Fax 603-588-2333