Discover how Axair Fans tackled a challenging Air Handling Unit (AHU) retrofit at the University of Oxford’s critical laboratories, delivering a robust, energy-efficient airflow solution.
When the University of Oxford needed to upgrade the air handling at its Environmental Sciences and Materials Facility (ES/MF), the stakes were high. This wasn’t just another HVAC job, this was about ensuring reliability for critical laboratory spaces, where downtime simply isn’t an option.
The existing fan system was a legacy double-inlet arrangement, with two motors, two belts, and one big problem: a single point of failure. For a facility where air quality and safety are paramount, this old setup posed a serious risk. Not only was reliability an issue, but efficiency and maintainability were falling short of what the University expected for such an important building.
The retrofit plan
From the outset, the team aimed to deliver a modern, future-proof solution. This meant utilising the benefits of a multiple fan array, an efficiency and redundancy-focused grid configuration of highly efficient plug fans. The pre-manufactured frame of the grid was fabricated and installed by AirHandlers Northern. This was then fitted out by Axair, which supplied and installed Rosenberg I-Wheel 450 EC plug fans and wiring cabinet. Wiring was completed to ensure future scalability with Modbus connectivity if required. Six fans were integrated into the wall, providing well above an N+1 redundancy setup, so if one fan went down, the system would continue to perform without compromising laboratory operations.
The scope of works:
Fan wall installation.
Removal of the old belt-driven fans and inverters, construction of a new wall with EC plug fans, and installation of a dedicated control enclosure for easier maintenance.
Flexible duct replacement
Survey and planned replacement of deteriorated flex ducting in the labs, with access challenges overcome using desk-surfer platforms.
BMS outstation upgrades
Progressive replacement of controls to bring Level 3 systems up to modern standards, with seamless integration to the University’s air quality and safety systems.
Every retrofit project has surprises, and Oxford was no different, but the team adapted quickly. Flexibility was key. Site inductions were arranged around university schedules, ensuring lab activity could continue while work progressed in the background.
The results
The new fan wall with six EC plug fans delivered a robust, energy-efficient airflow solution with true redundancy, the upgraded BMS outstations now provide real-time monitoring and tighter integration with laboratory systems, and the strong teamwork across contractors and University staff meant challenges were met head-on, with minimal disruption to ongoing research activity.
So, what lessons were learned from this case study? Firstly, always plan for the unexpected, access and services are rarely as straightforward as they appear on paper, clear communication between disciplines is critical when electrical, mechanical, and safety systems overlap, and N+1 might be standard, but designing above N+1 gives clients the peace of mind they need for critical environments.
Conclusion
From removing outdated belt-driven fans to installing a modern EC FanGrid, the Oxford labs project shows how retrofitting isn’t just about replacing like-for-like. It’s about rethinking reliability, safety and efficiency, and delivering solutions that will serve demanding facilities for years to come.
To learn more about how Axair’s AHU retrofit capabilities can transform reliability, efficiency and redundancy in critical environments, get in touch with the Axair, or learn more about AHU retrofit using a multiple fan array visit its solutions page.
https://www.axair-fans.co.uk/axair-industrial-fans/ecfangrid-ahu-multiple-fan-array
