Aggreko Oman was contracted to provide a temporary power and cooling solution to a laboratory building at a university hospital. The objective was to cool two floors of the laboratory. Aggreko’s involvement became necessary because the installed main, 60,000 CFM-capacity air handling unit (AHU) at the laboratory had suffered a major failure and could not be repaired. A temporary fix was put in place by the hospital’s maintenance department, which would enable continued laboratory operation until a new AHU could be fitted.
However, in addition to air handling capacities, the temperature in the laboratory building had to be maintained at 25 deg C and this presented a major challenge.
Each floor in the laboratory measured 15 x 60 x 3m and was fully enclosed in a concrete structure, with a clear ceiling with duct (inlet and return) in order to give full view of the hospitals laboratory.
To maintain the appropriate temperature within the laboratory, the AHU had to deliver 22 deg. C at the customer ducting inlet, which was located 27m from the Aggreko AHU, with no return air coming to the AHU. In a hospital laboratory, return air is not allowed to recirculate unless high-efficiency particulate arrestance (HEPA) filters are used and bacteria-eliminating infrared light filters are in place.
Aggreko provided cooling through flexible 500mm ducting, with chilled air from two 500 kW and two 300 kW pre-cooling AHUs that supplied the main AHU (70%) and provided fresh air (30%). The AHU was situated near the building. Two 750 kW air-cooled chillers, complete with pumps and buffer tank, were located outside.
Why was Aggreko selected?
The Aggreko solution fulfilled customer requirements, enabling the university hospital to replace its old AHU without the need to re-locate or shutdown laboratory facilities. Laboratory operations continued without disruption throughout the replacement programme.