MORRISVILLE, VERMONT—Kevin Amyot had serious qualms last spring when contractor Ed Friedrich first proposed a major pump-retrofit project at the Sunset Motor Inn, one of the properties Amyot manages for the H. A. Manosh Corporation in Morrisville.
Friedrich’s $13,000 estimate called for the replacement of 18 fixed-speed circulating pumps in the heating system at the Sunset with 10 circulators from the Grundfos Pumps Corporation. Six of the pumps would be conventional, fixed-speed circulators.
But the remaining four replacement units would be energy-saving, variable-speed, Magna smart” circulators. This quartet coupled ECM (electronically commutated motor) technology with sophisticated electronics for matching pump output to changing system demand—automatically and without human intervention—delivering substantial energy savings in the process.
Amyot was impressed with the new technology, and not just in the abstract. Friedrich had already done a successful retrofit at the home of company president Howard Manosh, and the latter’s downsized electric bills provided eloquent testimony of the energy savings the new smart circulators could provide. (More on this initial project in a bit.) Still, $13,000 was a hefty outlay to update a system that continued to function at an acceptable level most days of the week. “At the outset, I just couldn’t see how we’d recoup our investment any time soon, “says Amyot.
Not that the older circulators didn’t have performance “issues” of their own. Installed in the 1980s, the pumps generated a fair amount of mechanical noise while moving hot water from the 500,000 Btu per hour, coal-fired stoker and two backup, propane-fired boilers in the motel’s mechanical room through hundreds of feet of pipe to Sunset’s 59-unit guest quarters. (The property also includes three stand-alone houses that are not part of the heating and domestic hot water system.) All the humming and vibrating was a frequent target for guest complaints.
Further aggravating the situation, the system operated 24/7/365—whether hot water was needed or not. Consequently, there wasn’t much opportunity for relief, even at night (thus, the guest complaints). Of course, that round-the-clock operation was also the most fertile ground for energy savings.
Then there were the maintenance headaches: Given the pumps’ age, repairs were many and often. Couplers inside the pumps would weaken and break, or their bearing assemblies would need rebuilding. And because a motel must never be without hot water, all such breakdowns were tantamount to emergencies.
Amyot estimates he spent between $1,000 and $1,500 each year on parts alone. For the sake of speed, internal personnel handled most repairs; but if he expensed their labor as well, the total annual maintenance tab would have approached $3,000.
One of the Best
In the end, the high regard Howard Manosh and Kevin Amyot have for the professional skills of Ed Friedrich trumped their worries over cost and payback. A 22-year veteran of the plumbing and heating industry, Friedrich worked with the tools for nearly 15 years before establishing County Plumbing & Heating with two other partners—Gina Lanpher and Tom Sheltra—in 2003.
Today, the Morrisville-based, 14-employee firm has eight service vans covering a largely rural trading area and is doing a variety of work: plumbing, heating and air-conditioning, and drain- and sewer-cleaning. “Ed is highly experienced,” says Amyot. “But he also stays abreast of the latest trends and keeps us informed of them. That’s what makes him one of the best boiler people in the area, in our opinion.”
So Amyot set aside his misgivings and green-lighted the retrofit project last summer. Following the successful three-day installation, validation of this decision came almost immediately in the form of a sharply lower electrical bill. In fact, after only three months of operation, Amyot was projecting an astonishingly swift payback of one year.
Total electrical consumption at Sunset in August 2011, the final full month using the old pumps, was 12,760 kilowatt-hours (kWh). (See Exhibit I on final page of this article.) During September and October, consumption declined 34 percent and 42 percent, respectively. In November, the beginning of the heating season in what was a mild autumn in the Northeast, consumption finished at roughly 4,400 kWh, a two-thirds reduction from August.
Translated into dollars, the hotel’s November electric bill was $840 versus $2,400 three months earlier. Amyot now expects the motel’s electricity usage will drop by half over the course of an entire year. “With the savings on electricity alone, I can see a payback of between 18 to 24 months.” But he also figures to need 20 percent less coal, since the stoker now fires strictly on demand, as opposed to 24/7. Meanwhile, maintenance has dropped to zero.