RENEWABLE FUEL
a flexible, corrugated pipe filled with foam insulation. The lines move heat invisibly to all locations.
According to Yates, a series of Watts Radiant Hydronex panels and a custom-crafted, all-copper hydroseparator they built for the main mechanical room receive heat from the buffer tank, or directly from the stand-by boilers. Combined with programmable controls tied to outdoor reset sensors and interior thermostats, these panels parcel-out heated water in varying temperatures to supply: • BTUs to feed an injection panel for the home’s high-temp base- board heaters and an 80-gallon, Bradford White indirect heater to satisfy domestic water needs; also to the downstairs where 2,000 lineal feet of 3/8-inch Onix EPDM rubber tubing is stapled and insulated to provide low-temp radiant heat
• Heat for the apartment (just a few feet from the main mechani- cal room), where baseboard heat and another Bradford White indirect water heater receive high-temp water; and where low- temp water supplies warmth for the master bath (more Onix staple-up), and the vaulted great room and kitchen where above-floor Onix was used, just below the surface of a new, floating laminate floor
• Warmth for the woodshop, where another Watts Radiant injec- tion panel and Taco variable-speed, Delta-T pump send heated
water through a network of 3/4-inch Onix tubing to several fan coil units ranging in size from 50 to 150 MBH. Fin tube base- board and cast iron radiators are also found here. “Merv could have used smaller lines for the underground, EcoFlex ‘highway,’” added Yates, “but over-sizing the pipe kept overall pressure down, allowing us to use smaller pumps to cir- culate system fluids.”
The workshop area included three zones piped directly from the Watts Radiant zone control panel using telestats. “Rather than installing a bypass pressure relief valve with that added expense and running a circulator at full power no matter what the load is, we chose to have the Taco Delta-T circulator stand in for compo- nents that would have been necessary for a conventional on/off operation,” explained Yates.
For the home, Yates used injection pumping so that they could more easily sip the energy required at varying flow rates while the injection pump could operate without needing to sense the changing flow rates for radiators, baseboard, radiant zones or the Bradford White indirect tanks.
The zone control panel for the apartment also incorporates the flexibility to either do injection or direct pumping by simply turning on-off valves conveniently located on the panel. l FON
www.fueloilnews.com | FUEL OIL NEWS | MAY 2011 31
