The 172-unit residential complex built in the early 1970’s, was served by (2) 4,000 MBH boilers and an 8” diameter combination domestic and heating hot water piping loop. Individual loops provided hot water to serve the fan coils, kitchen sink, lavatory, and tub/shower for 4 units. The existing boilers did not meet local emission standards and were no longer available. Our team was faced with the challenge of replacing the heating source for a fully occupied facility.

Project Requirements

Replace an existing central hot water heating plant while minimizing the interruption to hot water delivery to the residents.

What Geo. H. Wilson Delivered

As the prime contractor, Geo. H. Wilson Inc. worked with local mechanical engineer, Young Engineering, to develop a modular design of (5) individual boilers that could be installed in a sequence to minimize periods of shut downs. During the design phase, we teamed up with San Jose Boiler Works to provide ZBI Infinite Energy Z IW-1000 boilers. We were able to lower the BTU’s by increasing the velocity of the water circulating in the existing loop. We were challenged by the constraint of supplying water hot enough for heating but low enough to meet code requirements while not being detrimental to residents. Our installation included a temperature mixing valve and 100 gallon buffer tank to insure that we met those goals.

The project duration was nine months, consisting of three months of design, two months to procure permits, two months for equipment lead time, and two months for installation. The serial nature of the project was required to meet the goals of minimized interruption to the residents. We met our contract budget with the revised contract price developed upon completion of the design.

Project Team

Owner: Villas of Capitola
General Contractor: Geo. H Wilson
Mechanical Engineer: Young Engineering