Some of our clients
Saturday 20th September 2014
St Mary's Hospital in Paddington (part of Imperial College NHS Trust) awarded the contract to replace one of its failed rooftop water chillers to JC Watson Refrigeration.
The buildings chilled water circuit was previously supplied by two Uniflair chillers operating in tandem. Both chillers had reached the end of their economic life, so JCWR was tasked with getting one chiller fully operational, by utilising working parts from both, then removing the donar chiller from site and replacing with a new Daikin chiller capable of running the entire building duty on its own. The remaining, operational Uniflair would then be utilised in times of excessive load or for future expansion of the chilled water network.
The site is accesible from one side only as it abounds the Grand union Canal. Access for the crane was severely restricted by the presence of London Underground tunnels and the limitations on vehicle axle loadings for vehicles transiting over, or along, the routes of the tunnels.
The size of crane required to accomodate the reach (85M) and lift (11 storeys) for this large chiller (8.8 tons) meant, under normal circumstances, that permission would be refused, due to the mobile crane axle weight being significantly over the maximum permissable set by London Undersground.
JCWR devised a unique solution to the problem, in that the crane was stripped down to its bare component parts, transported to site on articulated lorries and reassembled on site. This negated the transport weight limitations for the roads adjoining the Hospital. At the end of the lift, the crane was disassembled once more for transportation.
All of the above arrangements, including structural engineering calculations and liason with LUGL and the Metropolitan Police (Traffic) were undertaken on behalf of the Trust by JC Watson Refrigeration. This included the design and implementation of a Traffic Management plan for the Trust, as Blue light Ambulances had to be re-routed during the course of the lift. significant liason with London Ambulance was also undertaken including walkie talkie marshalling of the local road netwrk to ensure all emergency vehicles were correctly directed.
The installation of the chiller included mains electrical power, BMS and 8" chilled water flow and return connections on the roof. All works were successfully handled as a turnkey project on behalf of the Trust by JC Watson Refrigerations dedicated Contracts Team.