Unit Vents, School Exhaust, Pool Boiler and Air Handling Unit: Code Compliance Assessment and Mechanical Design

Pine Bush High School, Pine Bush, NY


Pine Bush High School needed to analyze its HVAC system to ensure that they met code compliance. MEP was subcontracted to conduct compliance tests and design mechanical and electrical systems.

MEP identified compliance issues and design upgrades to the existing HVAC system to make it more efficient and code compliant. Our building inspection also resulted in an additional mechanical ventilation study project.

Facility Description

Located in Pine Bush, New York and built in the 1970’s, Pine Bush High School is approximately 300,000 square feet consisting of two floors and a fractional basement partially underground.

Project Origin and Goals

This project originated as an energy performance contract by Ameresco in 2008 and targeted three mechanical systems consisting of classroom unit ventilators, exhaust for the entire school and new oil-fired pool summer boiler.

MEP conducted a technical and code compliance assessment of the entire building’s HVAC system as the design documents underwent full SED review and approval. Design of mechanical and electrical trades was included in MEP’s scope as the sub-consultant to the prime engineering company.


The Olympic size natatorium and spectator seating area are used extensively throughout the year. The space was served by a 10,000 cfm 100% outside air ventilation system equipped with split refrigerant dehumidification and tied into the central plant heating hot water boilers installed in 1991.

The air was exhausted via two rooftop exhaust fans. The existing system required extensive routine maintenance and was unable to maintain space conditions. The objective of the project was to replace the air handler with a re-circulating rooftop air handler and provide a summer boiler to serve the natatorium and the building’s domestic hot water needs.

MEP designed the installation of a 70% re-circulating 10,000 cfm rooftop system with refrigerant economizer and pool water heating capabilities. The design called for approximately 100 feet of new rooftop ductwork and 200 linear feet of pool water heating piping. A 700 MBH oil-fired boiler, associated hydronic pumps, fuel oil pumps and controls were designed to be installed within central plant boiler room. The boiler room was redesigned to provide sufficient combustion and dilution air.

School Exhaust

Approximately 44 classrooms and 8 miscellaneous areas were served by roof mounted gravity exhaust ventilators. This equipment produced excessive infiltration during the winter months which contributed a major energy loss component to the overall proposed savings. The gravity ventilators were replaced with approximately 25 exhaust fans, most of them serving two or three adjacent spaces.

Unit Ventilators

Twenty one rooms were equipped with unit ventilators that did not have provisions for outside air. MEP designed the installation of unit ventilators with outside air and economizer capabilities after evaluating central plant heating hot water capacities.

Building Inspection

MEP was also retained to carry out an inspection of the entire facility. Fifty one key areas and systems were examined and evaluated for NYS Building Code, SED guideline, and overall occupant safety compliance.

Among the inspected areas were ADA, egress passage, egress windows, materials handling and storage, door hardware, heating and cooling equipment, dual fuel firing control system, automatic and manual fire suppression equipment and alarms, outdoor air compliance, hot and cold water supply and distribution systems, plumbing fixtures, electrical systems, and communication systems.

The result of this inspection generated a separate project for MEP; a study in which every mechanical ventilation system was evaluated in depth (discussed in detail under another project narrative).


The school controls system was pneumatic in origin. Installing a new DDC based Building Energy Management system and associated retrofit of actuation apparatus was part of the scope for this project.