Lewis Palmer School District Admin Building Renovation

This project involved renovation of a historic school building to serve as the school district administration building. The 20,000 SF facility on three levels houses administrative offices, a training facility, and a district-wide computer network hub. AutoCAD drawings of the facility were not available initially. Schendt Engineering Corp. prepared AutoCAD background drawings based on existing drawings and site verification, then developed comprehensive mechanical and plumbing as-built drawings showing site-verified locations of existing boilers, radiators, unit heaters, steam piping, water heaters, and plumbing systems.

SEC evaluated new mechanical systems while giving particular attention to preserving the building's historical aspects. Initial client interest focused on heat pumps tied to city water distribution mains. However, two critical concerns emerged: winter water flow demands could not support capacity requirements, and concern about increased water main temperatures in summer potentially contributing to legionella growth. To address these issues, a geothermal ground-coupled heat pump system utilizing vertical heat exchangers was selected as the optimal solution.

A key challenge with heat pumps is achieving adequate heating capacity given ventilation requirements on cold days. To overcome this, a heat recovery wheel was installed to recover heat from the exhaust air stream to preheat outside air. This wheel achieves 70% effectiveness in recovering exhaust air heat, thereby eliminating the need for supplemental heating and optimizing system performance across all seasons.

The geothermal heat exchanger sizing was driven primarily by the cooling load of 60 tons, including the school district's internet hub computer room. Based on soil conductivity testing and calculated annual heating and cooling loads, the system required 42 vertical wells, 300 feet deep, to provide necessary capacity. Wells were split into 6 distinct reverse return loops to maintain system reliability in case of leaks. The complete system serves 60 rooms with 35 heat pumps providing independent zones of control for optimal comfort and energy efficiency throughout the facility.