Domestic Hot Water and Swimming Pool Heating
Project (Spring 2010): Reduce Hot Water Heating Cost
Place: AM Properties - Rockland, Maine
Purchaser: (Contractor) A&M Plumbing & Heating - Rockland, Maine, (Wholesaler) F.W. Webb, (Manufacturer's Rep) Dan Davis Sales
Andy MacMillan, owner of AM Plumbing & Heating and AM Properties is focused on high end vacation rentals on the coast of Maine. He realized that one of the largest expenses in his rental units was producing hot water. The units house up to 15 people and have four bathrooms and many bedrooms. Being in the plumbing and heating industry, it made sense for Andy to research solar hot water systems.
After carefully researching solar system design options, he realized that not only could he produce the majority of the domestic hot water demand from solar, he could also utilize excess heat produced in the summer to heat his pool.
Andy decided on using five Caleffi 4’ x 6.5’ ft. flat panels. Mounted in the awning style – the panels also serve to shade his porch. He used a Caleffi 120 gallon dual-coil solar hot water tank as a preheat tank and an iSolar™ Plus Controller to power the solar circulator and to control the Caleffi 3-way zone valve to divert excess solar heat to his pool. In the non-swimming months the iSolar™ controller also powers a second circulator connected to the upper tank coil. This allows any excess solar heat to be added to his radiant slab thereby reducing fuel consumed by the boiler.
A year after the installation, Andy was very satisfied with the solar system performance. It reduced his gas water heating bill by 20-25%, kept his pool warmer, and served successfully as a functional show piece for his customers.