All common areas in Phase 1 and the cottages have radiant heat under the floors, and all of the units' walls are insulated with urethane to prevent cold air infiltration in Montana's chilly winters.

In the building business for 30 years, and as general contractors for the past 15 years, Don and John Murray, of Murray Brothers Construction, entered the design-build business in the early '90s. They are part owners of the Century Village development, which is operated by an outside management company. Lowell Springer, A.I.A., of Bozeman, Mont., is the architect on the project. The mechanical contractor is PhD Mechanical of Helena, Mont.

The Murray brothers had initially thought of installing a lower-cost package terminal air conditioning (PTAC) system for summer cooling needs. They were sensitive to operating costs, however, because their plans did not contemplate a sale of the property after its completion. Meanwhile, Springer was looking for an innovative comfort system with lower operating costs for the project. In the end, the prospect of a hydronic system with an integrated piping system lent itself to a LoadMatch Tri-Water solution.

Single Loop Cut Costs

Springer invited Taco Inc., Cranston, R.I., to propose a LoadMatch system that would provide an integrated piping system, combining heating, cooling, and fire protection. The resulting system employs 55 water-source heat pumps instead of PTACs. When supplemental heat is needed on very cold days, the system's more efficient and lower operating cost, natural gas boiler is designed to provide it.

Because LoadMatch is a single-pipe system, heat, cooling, and support for the fire sprinkler system all come directly off the main (single) pipe loop. In essence, the HVAC piping was free. Less expensive installation costs were achieved due to the fact that one pipe could provide water for all three functions. In the end, less pipe was needed and no ductwork was involved.

Taco said its LoadMatch system is designed to provide better comfort than DX air systems, or conventional four-pipe hydronic systems. The manufacturer said the system is self-balancing and eliminates the need for most balancing valves by replacing them with small, energy-efficient LoadMatch circulators. The LoadMatch circulators are designed to direct water to where it needs to go, as opposed to forcing the water through the system's piping loop.

In the case of the Century Village project, the system solution brought the project costs for heating and cooling into line with the developers' budget for the project. Plus, the system is expected to provide the owners almost $27,000 in energy savings in just a few years.

"The LoadMatch system is functioning very well, and our residents enjoyed a comfortable summer," said Don Murray. "In terms of indoor comfort, we expect the system will do just as well when the cold weather arrives."

Publication date: 11/21/2005