University of Maine at Presque Isle Cuts the Carbon with Variable Refrigerant Flow Heat Pumps and SEMCO Energy Recovery Ventilators

  • Tuesday, June 15, 2010

    Columbia, MO - June 15, 2009 - The University of Maine at Presque Isle was among the first American universities to join the American College & University Presidents Climate Challenge. As a signatory of the agreement in early 2007, university president Donald Gillman committed the campus to a rigorous plan to reduce its carbon footprint. A unique HVAC renovation at Folsom-Pullen Hall was among the first success stories in the university’s trek toward carbon neutrality.

    Folsom-Pullen Hall is one of the primary educational buildings on the Presque Isle campus and includes classrooms, labs, and the university’s major lecture hall. It had not received any major mechanical upgrades since being built in 1966. So for decades faculty and students were subjected to excessive mechanical noise and wildly fluctuating indoor temperatures, while the university had to pay the bill for the substantial inefficiencies.

    An in-depth evaluation conducted by Mechanical Systems Engineers of Yarmouth, Maine, showed a heat loss of 1,604,188 BTUH for the Folsom wing (assuming 15 cfm/occupant) during occupied cycles. The steam heated unit ventilators located on the outside wall in every space, did not incorporate any heat recovery. This, combined with insufficient sealing around the ventilators, accounted for 51% of this total heat loss when the units were in operation.

    Not only were the unit ventilators an energy sieve, they were the source of some very intrusive rattling in classrooms and required constant maintenance. Their replacement, and the associated replacement of an outdated oil-fired steam boiler serving the Folsom wing, would go a long way in helping the university reduce its carbon footprint.

    Several solutions were considered for upgrading the HVAC system, but ultimately Kurt Magnusson, PE, of Mechanical

    Systems Engineers advocated a combination of a central energy recovery ventilator (ERV) by SEMCO and a variable refrigerant flow system (variable speed heat pumps ). This solution would result in the best payback for the university while affording students and faculty the added benefit of air conditioning during summertime classes.

    Decoupling the ventilation from the HVAC served a couple of purposes. First, a separately ducted ventilation system would eliminate most of the noise associated with conditioning the building. Second, it allowed for maximum energy recovery from exhaust air. A SEMCO FV-5000 energy recovery ventilator with an electric preheat coil proved ideal for this cold climate application.

    For complete details about SEMCO FV-5000 helped the University of Maine go green and learn about this winning combination of technologies see the case study.