RETROFIT | HYATT PLACE HOTEL Right: The basement-level restaurant The retail units meant all piped services from floors nine down to two, including drainage, had to be routed at high level along the first-floor corridor recovery. Wastewater from the hand basin, shower and WC is piped to the basement to a combined outfall for connection to the sewer. The hybrid VRF system features both refrigerant and water. In simple terms, refrigerant is circulated from the roof-mounted condensers to a DRAINAGE SYSTEM a heat exchanger. Water is circulated on coolth from the distribution box to the FCU in each room. A hybrid, rather than a full refrigerantcharged, VRF system was used to avoid the need to install a refrigerant leak-detection system in each guest room. Refrigerants are there is a leak. For compliance with BS EN378, where refrigerants are present in an enclosed space you either have to demonstrate that the volume of refrigerant charge able to leak into a single room doesnt exceed a set criterion, throughout the building and in each guest room, of which there are approximately has capability to detect a leak and to pump down the charge from the system to remove it from the unit, says Williams. The droplets evaporate to reduce the temperature of the gases and smoke in developing the energy strategy, which in combination with a new, high-performance faade enabled the project to achieve a CO2 reduction of 45% beyond Part L, as stipulated by the London Borough of Tower Hamlets. In addition to the inherent occupant safety of the hybrid VRF system, the hotel has a room. Mist systems use much less water than conventional sprinkler systems, which helps reduce the volume of water stored. We opted for a mist system 3 sprinkler water tank into the basement meant we would have lost about a third of the basement, which had to accommodate the kitchen, restaurant and gym, reduced time out of operation for repairs if a head were to discharge. 44 October 2021 www.cibsejournal.com CIBSE Oct21 pp42-45 Hyatt hotel Supp.indd 44 24/09/2021 15:22