MidCity Place

AHU & CHW Infrastructure Upgrades

Project breakdown

Decarbonisation project located in Central London.

We successfully improved the building’s EPC rating to a “B” with a score of 48.

The work was finished in phases to prevent any disruption to the operational building, which was fully occupied.

Phase 1

Our engineers have completed multiple projects within live environment of MidCity Place. Our works have included AHU “pod” upgrades, chiller replacements, and CHW infrastructure upgrades.

The initial set of works at MidCity Place was a multi-phase chiller replacement project using state of the art energy efficient chillers. We carried out a full energy audit and design review as maximising efficiency was paramount to the client. Project works included a new site wide water filtration and treatment system and upgrades to the existing heat pumps.

Our project team created a detailed phased changeover methodology, which risk and fall-back planning, to prevent the loss of any cooling services throughout all parts of the building whilst our works took place.

Crane lifts were organised and co-ordinated to allow the removal of an existing chiller to coincide with the delivery of its replacement. Our enhanced programme enabled us to maintain operation of 3 out of the 4 chillers at any one time.

Because of our excellent delivery and risk mitigation procedures we were retained to undertake works to the AHU “pods” located upon the roof. Each “pod” contained an AHU, CHW coils and circuit, a boiler, a BMS system, and associated services to provide environmental control in a single package.

Our engineering staff co-ordinated the modification of the structure of each AHU “pod”. We enabled the installation of new, larger cooling coils, and then managed the full refurbishment of each AHU, keeping the AHUs live and partially operational as the works progressed to completion.

We were initially appointed at MidCity Place to provide an emergency temporary chiller when an existing unit failed.

Our staff utilised their strong relationships with TfL and City of Westminster Council to arrange for a crane lift and chiller delivery within 2 weeks of appointment, preventing the building from overheating during the summer period.

Relationship building was key throughout the project. It was these strong relationships that allowed us to agree services shutdowns with both Hurley Palmer Flatt and the building’s operations team 2 weeks in advance. During one of our project workshops, our engineers ran through the scope of the shutdown so the on-site operations team could fully understand which services would be out of use.

When re-commissioning systems and bringing them back online, we ensured that all testing of new plant had been completed, and that any system livening up took place out of hours.

We worked with the incumbent BMS contractor to ensure that our new works were compatible with the building’s existing BMS. We integrated the BMS contractor into our team whilst procuring the new plant, ensuring compatibility and client confidence.

Phase 2

The principle of the air handling unit (AHU) decarbonisation project was to remove the combustion of natural gas as the source of heating to the fresh air supply to reduce the energy consumption of the AHUs, and in turn assist in improving the building’s EPC rating, by adding heat recovery between the supply and extract air streams and utilising air source heat pumps (ASHPs) to provide the heating and cooling to the fresh air supply.

The building was occupied during the AHU decarbonisation works and the project was undertaken in a phased manner, with the AHUs operating during occupied hours in a temporary condition whilst they were being refurbished. We provided the design and installation of the entire electrical and mechanical services installation associated with the AHU decarbonisation works.

The works consisted of mechanical ventilation validation, maintaining AHU temporary operating conditions, packaged plantroom strip-out and plantroom modifications, air handling unit modifications, runaround coil heat recovery and the replacement of multiple supply and extract fans through the building. We also provided the thermal insulation to the mechanical services and the acoustic equipment and acoustic treatment to the mechanical services installations.

In addition, we also provided the secondary support steelwork and access platforms and ladders associated with the electrical services installations. The testing and commissioning of both the electrical and mechanical services installations, the provision of operating and maintenance manuals and record drawings for the completed electrical and mechanical services installations. The provision of co-ordinated working drawings for the entire services installations and the provision of the services design calculations, drawings, schedules, wiring diagrams and control descriptions.

One of the primary challenges encountered was the structural constraints within one of the plant rooms, which made it impossible to install the cooling coil in its originally planned position due to the limited space between the attenuator and ductwork. To address this, we implemented a practical solution by installing a slimline attenuator at roof level, ensuring compliance with local authority acoustic criteria. This adjustment allowed the EF coil to remain within the plant room while the attenuator was relocated to the roof.