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Commercial Office · Braintree, MA

A phased approach restores VAV rooftop performance before winter sets in.

KS Partners contracted FMC Technologies to develop a turn-key solution for their 300 Granite Street property that would immediately deliver cost savings and improve occupant comfort through tailored HVAC optimization.

300 Granite Street building
300 Granite StreetBraintree, MA
<6wks
Phase I completion
12
Stages of cooling control
2
Implementation phases
The challenge

Broken VAV controls put building performance at risk.

In 2018, KS Partners acquired the commercial office building at 300 Granite Street in Braintree, Massachusetts. They immediately identified significant issues with the control of its variable air volume (VAV) rooftop units — problems that created high HVAC system operating costs, excessive equipment failures, and a poor tenant experience.

The building's VAV rooftop units' control system was missing several key control points, leaving it unable to provide precision control of the units' 12 stages of cooling, electric heat, and its economizer. This fundamental gap in control infrastructure meant the system was operating far below manufacturer specifications and optimal performance.

  • Issue 01

    Missing control stages

    The VAV unit control system was not fully installed and did not adhere to manufacturer-specified load/unload sequences, leading to improper cycling that damaged several compressors.

  • Issue 02

    Harsh economizer control

    The VAV unit economizer dampers were subject to harsh, binary on/off control rather than the intended smooth control modulating based on outdoor and indoor air conditions.

  • Issue 03

    Limited terminal control

    The terminal boxes lacked direct digital control, reducing their control capabilities including localized control and night set-back systems, adversely impacting overall operation.

The solution

Phased HVAC optimization with EMS integration.

FMC designed a fix for the VAV rooftop units and rolled out a building-wide EMS around it — in two phases, because getting Phase I done before winter mattered more than getting everything done at once. The tenants didn't notice the work; they noticed that the building stopped swinging.

  1. Phase I
    Staged compressor installation. FMC installed the required control points and staged the compressors as prescribed by the rooftop unit manufacturer, preventing future damage and creating energy savings opportunities.
  2. Phase I
    Enthalpy-based economizer. FMC implemented an enthalpy-based economizer with more efficient changeover settings incorporating humidity levels and installed resets that would connect to the EMS in Phase II.
  3. Phase I
    Interim zone control. As an interim solution, FMC added zone-based scheduling and night setbacks to improve performance until the EMS installation in Phase II.
  4. Phase II
    Building-wide EMS. Phase I's groundwork made for a smooth, flexible transition to the building-wide EMS implementation — a robust platform for future energy optimization and advanced building intelligence.
The results

Immediate improvements and a foundation for growth.

FMC completed Phase I of 300 Granite Street in less than six weeks from approval, and the building consistently maintained a comfortable interior temperature immediately after implementation. The indoor environment for the building's tenants improved substantially, with more consistent thermal control and reduced HVAC-related failures.

Beyond the immediate comfort and efficiency gains, FMC's work in Phase I laid the essential groundwork for a smooth and flexible transition to the Phase II building-wide EMS implementation. By addressing the foundational control issues first, the organization created a robust platform for future energy optimization and advanced building intelligence.

Let’s talk

Got a plant that needs to come back online before winter?

Phased retrofits are our bread and butter — we're used to working around tenants, budgets, and deadlines that don't move. Tell us what you're up against.

Talk to FMC
Or call 978·856·7862