Transforming Suffolk Council’s Chambers Air Handling System.
Airway was contracted as a specialist sub-contractor by Dalkia, a part of the EDF group, to enhance the air handling system at Suffolk Council’s Chambers.
The existing system consisted of two separate AHUs and a rudimentary recirculation setup, providing heating through low-pressure hot water coils and cooling using outdated DX units.
In 2022 phase one commenced. Working in tangent with Suffolk County Council design team Concertus a new VES Heat Recovery AHU system was delivered to site in Ipswich. The old plant was all safely de-commissioned by our trained engineers ready to be crane lifted off the roof.
Airway and Dalkia coordinated with Ipswich Town Football Club to utilize their car park facilities for crane operations to remove the old equipment from the roof and install the new system. This occurred on a Saturday morning, involving the placement of a VES MAXI31 heat recovery AHU, two Mitsubishi R32 Heat Pump Condensers PUZ-ZM200, and the Mitsubishi PAC-I control interface.
Our team piped up the refrigeration system and control cables as well as modification and extension of some large 800x650mm rectangular ducting from the new AHU into the roof pods and connected onto the existing ductwork following into the Council Chamber. All the ducting was fully insulated with a weatherproof outer covering also installed.
During this period, Suffolk County Council and their designers at Concertus decided to make several specification changes. Airway engaged the VES site team to transition from a single-stage Heating/Cooling coil to a two-stage model. Additionally, adjustments were made to the control strategy based on the client’s preferences, and VES returned to integrate the system with the site’s Building Management System.
After all these changes the system was commissioned, and airflows read to prove the 1.47m3/sec on both supply air and return and in time for winter season at the end of September 2022.
The existing method of getting air into the chamber was via a number of floor grilles where supply air was pumped into a floor void and allowed to try and reach each floor grille with no means of volume control. Return air was via a Bell Mouth Return above a plasterboard ceiling where small open vents were cut into the ceiling to allow rising hot air into the void. This approach proved inadequate, necessitating the exploration of an alternative solution.
Collaboratively, Airway, Dalkia, and Concertus developed a new internal ducting plan. This plan included cutting back the supply air ductwork where it dropped into the floor void and installing new ducting and 8no. Waterloo Swirl Diffusers into the ceilings. It also required the existing Bell-Mouth Return air ducting to be changed to new ducting and connect also to 8no. Swirl diffusers. This would allow far more controlled airflow on both supply and return air into the chamber.
We successfully completed all our tasks, including comprehensive air flow testing and balancing, two days ahead of the revised schedule. This allowed us to meet the handover date of Monday, September 11th, as planned. The following day, a full Suffolk council meeting proceeded with over 120 delegates in attendance.