Mission High School, located around the neighborhoods of Castro and Upper Market, is one of eighteen high schools within the San Francisco Unified School District (SFUSD). It relies on two steam boilers to heat their radiators that are spread throughout the classrooms and hallways, one of which had already failed and was abandoned. The second boiler was past its useful life and had frequent mechanical failures.
As the prime contractor, ACCO sought out subcontractors for electrical, controls, concrete, demolition, insulation and abatement. However, the largest obstacle was to remove and replace the two existing 4,300 MBH cast iron steam boilers that lay underneath the school in the mechanical room pit. The project took place during the summer when school was out and needed to be substantially complete prior to the start of the next school year.
What ACCO Delivered
With limited access and elevation differences within the path of travel, ACCO took this obstacle head on and produced engineered solutions by building site-specific rigging equipment to rig the new boilers in by sections. The mechanical pit also had very high ceilings, so ACCO designed pipe stands in order to support the steam header, equalizer piping and flue.
In addition to the steam boiler system, the sump pumps were also recommended to be replaced to protect the schools’ new investment. ACCO achieved the target schedule of completing the replacement before the beginning of the school year and stayed on budget. Once school started, ACCO pulled trend data in order to modify the control set points for accuracy.