When T Mobile and their nominated Facilities Supplier needed to replace their aging and troublesome chiller plant at their switching centre in Sunbury, they contacted Accent Services with a brief of
their requirements.

Calling on their 30 year plus experience and following in depth site appraisals, Accent put together a proposal that whilst meeting the Client’s specification, included significant changes to the plant so that T Mobile could move forward with a simpler and easier to maintain system.

Less is more

As a result of several changes within the Centre the existing system had grown and become complex relying on 5 chillers and 4 separate pump sets in operation, whilst still not providing true standby to all areas.

With Accent’s changed design only 3 chillers and 2 pumps are installed, with 1  chiller and pump purely for standby purposes. Projected savings of £30K per annum in energy costs are anticipated as a result of the new installation.

The new chillers operating on ozone friendly R134a refrigerant, utilise fully modulating screw compressors which precisely maintain system temperatures and avoid the on/off control of the previous units.

No time for down time

A major factor for this project was that it was not possible to shut down any areas during the upgrade, indeed  T Mobile insisted that standby plant was also in place.

A number of options were investigated from start to final completion to ensure a seamless transition from old to new.  This was finally achieved by installing temporary plant in certain key areas on a staged basis, to allow access points to be installed on the chilled distribution system.  It was then possible to install a complete temporary chiller and pump system to hold the building, whilst systematically replacing all redundant equipment and services over a three month period.

Hot stuff

Before a newly installed system can become operational, it must undergo a rigorous and thorough test schedule.T Mobile were left in no doubt as to the reliability of their new system as the test date fell on the hottest July day since records began.

Project facts at a glance

• c.£30,000 a year reduction in energy costs
• System simplified, reliability increased
• Built-in standby plant
• Zero ‘down time’ for customer
• Ozone depleting refrigerants removed