The Challenge

An older office building had constant-volume ventilation with no recovery. Energy bills were high and the system could not meet current efficiency expectations for a lease renewal.

The Solution

The existing air-handling unit was retrofitted with a crossflow plate exchanger and variable-speed fans. Ductwork changes were minimal because the core slotted into the AHU section.

Results

• Fresh-air heating load cut substantially in winter
• Improved indoor air quality through steadier ventilation
• Payback achieved within a few heating seasons

Lesson

Retrofits favour compact, simple exchangers. A crossflow plate core delivered most of the savings of a wheel with far less disruption.