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As I See It

Days of on-off control are fading

We ran a story a couple months ago about a project that’s called the Anchor Homestead, a 4,500-sq.ft. 1850s farmhouse on Boston’s south shore that started its life with a gravity steam system. It wouldn’t be much of a stretch to guess that it was originally coal-fired. It’s projects like this that make me think about how far we’ve come.

Naturally, the heating system had been “upgraded” over the last 150 years to the point where it no longer functioned.  Our story talks about how Rich Swatton, president of ModCon Service & Support Inc., Westford, Mass., and his cohorts fixed the home in Hanover, Mass. All of the old black iron pipe was ripped out and replaced with PEX with supply and return lines going to each heat emitter. The PEX was manifolded and fed by ECM variable-speed circulators. In the basement, a modulating condensing boiler with a 5:1 turndown ratio and outdoor reset supplies hot water.

That’s a long way from shoveling coal into a gravity steam boiler. The days of on-off control are fading too, an not just in an old farmhouse in Hanover, Mass. Modulating, condensing, variable speed, variable water flow or variable refrigerant flow were all over the recent AHR Expo in Dallas. We begin our AHR coverage on page 1 of this issue, written by Senior Editor Candace Roulo and myself. We only have a limited amount of space in this issue and I would encourage you to read the entire 3,000+ word story on We’re planning on turning all of the product photos from the show into a slideshow to accompany the story.

For example, Grundfos introduced its Magna 3 commercial hydronic circulator that the company says will reduce energy use by 85%. The AutoAdapt function allows the variable-speed ECM-based circulator to use an integrated logic algorithm to “learn” the varying energy-usage patterns of an application over time, enabling the software to automatically determine the most efficient operating point.

Both ClimateMaster and WaterFurnace have taken already efficient geothermal heat pumps and converted them to variable capacity with EERs in the 40s.

Xylem previewed its integrated VFD sensorless control on Bell & Gossett in-line pumps. Available in the second quarter of 2013, the variable-speed drive sensorless controller uses advanced pumping software and algorithms to create an energy saving pump system.

Taco introduced its GeoSentry Geothermal Zone Valve that uses microcircuit-based logic to activate a gear-driven, electronic actuator.

Lochinvar’s Armor wall-mount commercial water heaters are not just 96% efficient, they use a Smart System operating control that includes a built-in cascading sequencer that allows for water heaters with different Btuh inputs to be installed together to maximize turndown capability.

I don’t have enough space to tell you everything that the ecobee thermostats can do, but let’s just say there’s an app for that. The Nest learning thermostat has gotten a lot of press lately but ecobee has contractor-friendly features, such as its Contractor Portal, which gives you a web connection into your customers thermostats, that you must check out. ecobee remains the go-to thermostat for professionals.

It was all that long ago that we didn’t have equipment that could “learn” usage patterns through software algorithms.

We’re a long way from shoveling coal. Think about how far we’ve come.


On a completely separate note, I want to welcome my friend, Eric Aune, to our pages. Eric has run Aune Plumbing LLC, a one-man shop in Zimmerman, Minn., since 2004, installing and servicing plumbing, hydronic, radiant, and solar equipment. He is also a veteran apprentice instructor at Dunwoody College of Technology in Minneapolis. Eric is going to write for us every month about his experiences and observations on being a small contractor. You can catch up with Eric at his Aune-Plumbing-LLC Facebook fan page and on his blog at where he writes rants with headlines such as, “Your brother-in-law did what?” He is also a co-owner, along with John Mesenbrink, of the website Eric lives with his lovely wife, Heather, and their two boys, for whom Eric is an indefatigable Boy Scout leader. He is also one of the funniest guys I know. I’m looking forward to seeing where Eric’s fertile mind takes us.

Follow me on Twitter @bobmader

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