A ground-floor restaurant was generating persistent cooking odors that migrated through the building’s air handling system to upper-floor tenants. Installing GPS-iMod directly on the air handler solved odor complaints with zero tenant disruption.
| HVAC Coil on Unit 3 | HVAC Coil on Unit 8 | |||
| Bacteria CFU/in2 | Mold-Fungi CFU/in2 | Bacteria CFU/in2 | Mold-Fungi CFU/in2 | |
| Swab 1 | 30,000,000 | 650,000 | 900,000 | 3,400,000 |
| Swab 2 | 20,000,000 | 500,000 | 20,000,000 | 2,800,000 |
| Swab 3 | 3,100,000 | 3,500,000 | 40,000,000 | 30,000,000 |
| Average | 17,700,000 | 1,550,000 | 20,300,000 | 12,066,667 |
500 South College is a multi-tenant commercial building with a ground-floor Indian restaurant and tenants on the upper
floors. During peak lunch hours, cooking odors from the restaurant were being drawn into the building’s outside air intake
at the rear of the structure. The air handling system then distributed those odors throughout the building, with the fourth-floor office tenant bearing the worst of it.
The ventilation design pulled restaurant cooking odors into the supply air and distributed them to every floor served by
that air handler. The second floor, occupied by a church operating only on weekends, and the third floor with limited daytime tenancy were less affected. But the fourth-floor tenant’s complaints were persistent.
For the building team, responsiveness was critical. Tenant complaints left unresolved erode trust and threaten retention.
Larry Reed, Assistant Chief Engineer at 500 South College, moved quickly. As soon as the complaint came in, Reed brought
in his trusted HVAC vendor to evaluate the situation and identify a solution.
After evaluating the airflow dynamics and odor pathway, Reed’s vendor recommended GPS-iMod, a simple modular needlepoint bipolar ionization system that is field-assembled in 6-inch increments to provide coverage across the coil width of commercial air handlers. The system was approved and installed in a single afternoon, mounted directly on
the existing air handler to treat incoming outside air before it entered the ductwork.
No ductwork modifications were required, and no tenant spaces were disrupted. Once installed, the results were immediate.
The GPS-iMod solution delivered:
Complete odor elimination across all occupied floors.
Zero tenant disruption during installation.
No ductwork modifications or mechanical rework.
No impact to the restaurant’s operations.
The fourth-floor tenant’s odor complaints stopped entirely. The restaurant continued full operations without any restrictions, and the building’s HVAC system required no additional modifications. A problem that threatened tenant satisfaction was resolved with a targeted, low-disruption solution that kept 500 South College’s reputation for responsiveness intact.
This project illustrates how GPS-iMod can solve indoor air quality challenges beyond energy savings and code compliance. In multi-tenant buildings where odor transfer between spaces threatens tenant satisfaction and retention, GPS-iMod’s soft ionization technology provides a fast, non-invasive solution that neutralizes the odor at the air handler.
For building engineers and facility managers facing cross-tenant odor complaints, GPS-iMod offers a path that avoids the cost and disruption of traditional mechanical fixes. Its modular design adapts to any air handler in 6-inch increments, and it installs without modification to existing equipment. This project delivered complete odor elimination in one afternoon, with no impact to tenants, no ductwork changes, and no ongoing operational
adjustments.
Questions?
