Plumbing / PVF Community

Sterling brings the innovation of solid Vikrell® material to its bathtub shower enclosures. Offering high durability, attractive appearance, and easy cleaning, Vikrell is a material ideally suited for the rigors of bathroom life.

Sterling also offers many bathtub showers adaptable to the Americans with Disabilities Act (ADA) requirements. Innovative features like grab bars, fixed seating, and convenient shelves make bathtub showers from Sterling appropriate for handicapped accessibility or other special needs.

Contact your local Marks Supply branch for more information

By: Dave Martin (Marks Supply – London)

A boiler can consume several times its initial cost in fuel in a year. That, coupled with escalating utility rates and an increasing focus on energy and the environment, has engineers and contractors turning to an ever-expanding array of super- efficient condensing hot-water boilers.

The greatest consideration in determining whether a gas-fired condensing boiler is right for a particular project concerns return-water temperature. Condensing boilers achieve high efficiency by capturing the additional heat released from condensing flue gas (up to 12 or 13 percent of the original energy content of the gas). For flue gas to condense, return water must be below about 140 F. For this reason, condensing boilers are most suitable for low-temperature systems, such as radiant floor heating, swimming pool or spa, dedicated water heating, snow melt, and water-source heat pump. The application of a condensing boiler to a heating system with a return-water temperature above 140ºF, such as a baseboard heating system, would result in a peak thermal efficiency of 88 percent and represent a squandered investment.

Condensing boilers offer a number of benefits, including efficiency, compact size, and low emissions. The field of available products is growing at a fast rate as technology advances. Stick with equipment with a track record of successful performance and documented maintenance. You will be glad you did. (continue reading…)

By: Tom Melnychuk (Marks Supply – Guelph)

Pump away is a common term heard in the Hydronics industry – reintroduced by Dan Holohan in his classic book “Pumping Away”. So we know to pump away, but from what? The Boiler? The Expansion Tank? The answer becomes clearer when we look at why we pump away.

• It “moves” water farther from its flash point. In other words, increasing the pressure on water helps suppress boiling.
• Molecules of dissolved gases are encouraged to stay in solution, thus ensuring quiet operation of the circulator.
• It helps eject any air that has accumulated in air vents.
• Air is prevented from being “sucked” into the piping circuit at points that might be drawn to sub atmospheric pressure when the circulator operates, due to incorrect design.

The only place this can happen is at the point of no pressure change – in a simple closed hydronics loop this is the expansion tank. See the attached diagram. If you follow this format you will greatly increase your customers satisfaction with their hydronic heating system, providing quiet comfortable heat.

By: Greg Thaler (Marks Supply – Burlington)

To size a Natural Gas Regulator you will need three things. Inlet pressure, Outlet pressure and the Flow requirements.

Inlet pressure is the pressure of the gas on the supply side usually 10, 5 or 2 psi. This can be determined with a pressure gauge (if there is one installed), referring to the mechanical drawings or by contacting the Gas Company. Outlet pressure is the pressure you are running the gas lines to the equipment at. This is measured in inches of water column (27.7”WC = 1psi). The majority of cases this is 7”WC. If your system requires a different pressure Norgas Actaris gas regulators can be adjusted by changing out the color coded springs.

Flow Requirement relates directly to the BtuH requirements for the equipment you are installing. Please note, in the charts attached SCFH means Standard Cubic Feet per Hour which equals 1000 BtuH for natural gas.

Inlet, outlet and Flow requirements will allow you to determine the valve type and orifice size needed. Always size over the required flow to allow for future additions and or over demand situations. Please note the line size is not a significant factor in determining the correct regulator. A ¾ gas regulator sized to the inlet, outlet and flow requirements will give you all the gas you need even when installed on a 1” line. If you require assistance sizing gas regulators please call your local Marks Supply branch.

By: Mike Willis (Marks Supply – Guelph)

CBV’s most often are selected based on the size of the line they are installed on, not the system’s designed flow through the line. Many systems have balancing valves that are set way outside their range of accuracy in order to meet the flow requirements of the design. This leads to poor control and wasted energy. Chose your CBV size based on the flow rate requirements for your system. The following chart will help you to choose the right valve for your system and eliminate the problem of improper CBV sizing.