Aircon Installations Ltd is an approved contractor for the Metropolitan Police and has carried out numerous installations throughout the London area, including the replacement of water chillers at Paddington Green police station.

The existing installation comprised a basement level plant room containing two water cooled R22 water chillers, installed over 20 years ago. Directly above the chiller room is the ground floor pump room containing both the chilled water and the condenser water pumps. The original installation incorporated an open cooling tower, some 15 floors above, on the roof of the accommodation block, which was subsequently replaced with a series of dry condensers, presumably as a result of legionella issues.

The use of dry coolers greatly reduced the original cooling output and resulted in the compressors operating at much higher temperatures.

We took this opportunity to rethink the entire solution, resulting in the installation of two package air cooled water chillers on the second floor roof. The original water cooled chillers were removed and the plant room was returned to the engineering department as much needed workshop / storage space.

The 15th floor roof was totally cleared of all equipment, the condensers being cut into small pieces and manhandled down through the building. This totally cleared the roof area for much needed communications equipment.

The original chilled water pumps pumped the chilled water across the second floor roof to a remote air handling unit plant room, which provided primary air cooling to the induction system. These pipes were uncovered and altered to accommodate the installation of two Daikin twin screw water chillers on new structural steel work, provided by ourselves.

The net result was a system working at much greater efficiency, providing some 500 kilowatts of cooling at much reduced running costs.