Project Details
Britannia Kings College is based at 7 Trinity Street, London SE1, a busy, well-established educational institution that depends on reliable building services to support students and staff throughout the year.
When the existing rooftop air handling unit reached the end of its serviceable life, the college engaged Weatherite Air Conditioning Limited to survey the installation, design a suitable replacement, and manage the full removal and installation programme. The result was a bespoke, high-performance AHU designed and manufactured in the UK installed with a total turnaround of just five days.
The Challenge
The existing Weatherite AHU had served the college for well over 25 years but was no longer performing to the current day building demands. A site survey was carried out to assess the condition of the unit, the constraints of the rooftop location, and the ventilation demands of the spaces it served.
The key requirements were clear:
• The replacement unit had to match the original footprint exactly. The rooftop location allowed no flexibility on size or configuration
• The college required a fast turnaround to minimise disruption to building occupants
• The new AHU needed to deliver improved performance and long-term reliability
• Removal of the old unit and positioning of the new one both required careful coordination at rooftop level
Our Approach
Following the site survey, Weatherite's in-house design team engineered a brand-new AHU built specifically to suit the rooftop constraints and ventilation requirements identified on site. By designing and manufacturing the unit ourselves, we were able to maintain complete control over the specification, quality, and programme — ensuring the unit arrived on site ready to perform from day one.
Our team worked closely with all parties involved to plan the removal and installation sequence carefully, keeping the programme as tight as possible while ensuring the work was carried out safely and to the standard the client expected.
Solutions
Weatherite Air Conditioning designed and delivered a complete AHU replacement, covering survey, design, manufacture, removal, installation, and commissioning. The solution featured:
• A bespoke air handling unit engineered to match the original rooftop footprint precisely
• The new 12.5m3/s AHU needed to fully modulate to meet the buildings usage and occupancy offering a considerable saving on running costs
• The new unit boasted R513A refrigerant in lieu of its R407c predecessor but still offered the 382 kw of cooling requirement over 4 tandem compressor sets giving exceptional control.
• The new unit had an upgraded Trend IQ5 control system and the software written also controlled the existing extract unit that had not been replaced.
• Full design, manufacture, and factory testing carried out at Weatherite’s UK facilities.
• Old unit safely removed from rooftop on a Saturday, with the new unit lifted into position the same day.
• Due to the restricted power supply on the site, we were unable to offer a heat pump version of the product, but we were able to improve on the old gas fired burners with highly efficient, fully modulating low Nox condensing burners.
• Connecting pipework and associated on-site works completed across the following days, with full commissioning finalised by Thursday
• The unit was pre-commissioned at the factory prior to the splitting of the two deliverable sections to minimise the installation programme to meet the clients needs.
Results and Impact
The project was delivered on time, within programme, and with minimal disruption to the college. By completing the physical removal and installation over a weekend, the impact on building occupants was kept to an absolute minimum. The total turnaround from removal of the old unit to full commissioning of the new one was five days.
• Five-day turnaround: from removal of the old unit on Saturday to full commissioning by Thursday
• Exact footprint match: no structural alterations or rooftop modifications required
• Improved performance: a high-specification replacement delivering reliable ventilation to the college
• Project value: over £190,000
• Minimal disruption: all major works completed over a weekend to protect normal building operations
This project demonstrates what is possible when survey, design, manufacturing, and installation all sit under one roof. From the initial site visit through to commissioning, every stage was managed and delivered by the Weatherite team — giving the client a single point of contact and complete confidence throughout.
Client Feedback
“Weatherite were the original manufacturer of our existing air handling unit, and it had reached the end of its functional and economic life, so they were the obvious people to speak to about a replacement. What made them stand out was that they could offer a new unit in the same footprint, with more efficient components and the quickest turnaround of any option we considered, and the controls and other components specified were all of a high quality.
We were happy with the cost, specification, build quality and delivery time of the solution Weatherite proposed. Everyone we dealt with was helpful with whatever issue was on the table at the time, and the controls expert, William, was particularly helpful and knowledgeable. I wouldn't say Weatherite exceeded our expectations exactly, but the speed with which problems were picked up and responded to was certainly well appreciated.
I would recommend Weatherite. They have shown themselves to be professional, knowledgeable, helpful and proactive in getting the project delivered, and the after-sales support has also been excellent.”
— Project Contractor, Britannia Kings College
