Choosing the Best Under the Boiler Accessories for your Next Installation

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In a hydronic system, every installation is an opportunity to improve efficiency. The products you select for the job not only impact the installation of today but the performance of tomorrow. This is especially true when installing a boiler; the components you pair with the unit can mean the difference between a simple installation and a smarter installation.

Auxiliary boiler accessories range in both form and function. The best products for the job should be designed to save time, space, and labor during installation. They should also provide controls to ease future maintenance and should protect the boiler and system components over time.

With these goals in mind, Webstone has developed the most complete selection of under boiler solutions available today. Its under boiler program is a single source for better installations, with products that also simplify and reduce the number of maintenance callbacks.

The Hydro-Core™ manifold simplifies the installation and service of the primary heating loop. This solution combines closely-spaced tees with isolation valves to achieve hydraulic separation for the heating loops, isolates the components within the loop, and purges the system. A T-Flow ball directs the flow into either the boiler or the drain, which can be configured in a number of ways to assist with purging, filling, and descaling/cleaning. Its compact, forged-brass body replaces up to 17 individual components, eliminates 16 leak paths, and saves over two hours of labor.

To improve overall system performance, the Air Separator uses a unique stainless-steel coalescing medium that captures both microbubbles and static air. The separated air collects in the top of the unit, where it forces a pin-guided float to drop down and open a vent. Once the air is released, the float rises once again and closes the vent. This reduces noise as well as wear on system components caused by trapped air in the pipes. The vertically mounted model is ideal for installing on the boiler outlet, where the air can be separated and vented before it reaches the rest of the system.

To protect the boiler from iron sludge that can accumulate in a hydronic system, consider the Magnetic Boiler Filter. Installed on the system return line, it captures ferrous and non-ferrous debris before it can reach the boiler using a high-powered 12,000 Gauss magnet and plastic filter. The drain makes it simple to remove accumulation, with a strapped cap that can be used to actuate the drain valve. A universal diverter allows the Magnetic Boiler Filter to be used in both horizontal and vertical piping orientations. The service tool is also included to help install and maintain the filter with ease.

Both the vertical mount Air Separator and Magnetic Boiler Filter are outfitted with removable G1 threaded end connections (available in sizes ¾” and 1”, with MIP, FIP, SWT, or Press ends), offering added versatility to any installation. These threads allow the installer to easily add isolation valves for future service, or a temperature gauge to verify boiler output right at the source.

A full-featured under the boiler installation from Webstone requires no more than 22” of space and delivers cleaner, more professional-looking results. Solutions are also available for boilers with external pumps and combi domestic hot water connections from the E-X-P™ Series of Tankless Water Heater Service Valves. To find all of these products and more, visit

Founded in 1954, Webstone now operates as a brand of NIBCO INC. and is recognized as an industry leader for innovative design of residential and commercial valves used in plumbing, hydronic, radiant, solar and geothermal applications. These designs focus on time and space-saving concepts that simplify future maintenance and upkeep of all piping systems. Some of the Webstone trademarked and patented items include Hydro-Core™, The Isolator®, E-X-P™, Pro-Connect™, and Pro-Pal® step-saving valves.

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