HVAC System Design Requirements
The Hilton Design Guide (HDDG) sets comprehensive and stringent requirements for HVAC systems. For heating and cooling sources, the integrated COP of chillers shall be no less than 6.0, and IPLV no less than 12.0. Cooling tower selection shall determine the leaving water temperature based on wet-bulb temperature + 3 degrees. Guest room areas adopt a four-pipe fan coil unit (FCU) system to enable independent cooling or heating, with fresh air processed dispersedly by dedicated outdoor air systems (DOAS) and delivered to guest rooms. The fresh air volume for guest rooms shall be no less than 50 m3/h per room (double occupancy standard), equivalent to 25 m3/h per person. The indoor CO2 concentration control target shall not exceed 800 ppm (stricter than the 1000 ppm standard in GB 50736), requiring a demand-controlled ventilation (DCV) system to adjust fresh air volume based on CO2 concentration. Guest room air-conditioning operating noise shall not exceed 28 dB(A) during daytime and 25 dB(A) at night (Hilton requirements are stricter than the national standard). Noise in public areas such as the lobby shall not exceed 40 dB(A). AHU units adopt variable-frequency fans, configured with G4+F7 two-stage filtration, with HEPA high-efficiency filters added at terminals (required by Hilton luxury brands). The kitchen air-conditioning system adopts a once-through system, with exhaust air volume calculated at 3000 CFM per standard cooking station. All air-conditioning fresh air systems shall be equipped with energy recovery devices with a minimum sensible heat recovery efficiency of 65%.
Electrical Systems and Intelligent Requirements
HDDG requirements for electrical systems cover four major subsystems: power distribution, lighting, intelligent systems, and low-voltage systems. The power distribution system requires dual independent power supplies with emergency diesel generator sets, with generator capacity determined by total hotel fire load + 50% guaranteed load + 20% redundancy. Transformer load rate design shall not exceed 75% to reserve capacity for expansion. Lighting system design shall meet illuminance standards: guest rooms 100-150 lx, lobby 200-300 lx, ballroom 350-500 lx, corridors 50-100 lx. LED luminaire color rendering index (CRI) shall be no less than 85 (no less than 90 for guest rooms). Dimming systems shall adopt DALI or 0-10V dimming protocols covering all public areas. Intelligent systems require: building automation system (BACnet protocol) to monitor all MEP equipment; room control units (RCU) to control air conditioning, lighting, curtains, door locks, and SOS calls; energy management system (EMS) for real-time monitoring of sub-metered energy consumption; IPTV system supporting guest room interactive services; full wireless network coverage (AP spacing no more than 15 m). HDDG also requires intelligent lighting systems to achieve on-demand lighting and scene control. Low-voltage systems require structured cabling with Category 6A or above cables, with fiber to the floor distribution room.
Plumbing and Fire Protection System Requirements
HDDG plumbing system design requirements include: domestic water supply system vertical zoning with water pressure not exceeding 0.45 MPa, with pressure-reducing valve assemblies provided in each zone. Hot water system delivery time shall not exceed 7 seconds (slightly more lenient than Marriott MIDS's 5 seconds but stricter than the national standard of 10 seconds), and return water temperature shall not be lower than 55 degrees to prevent Legionella growth. Hot water systems are recommended to be equipped with solar preheating devices providing no less than 30% of the domestic hot water heating load. Sanitary fixtures shall be standard water-saving products—water closets no more than 4.0 L per flush, showerheads no more than 8.0 L/min. Fire protection systems shall simultaneously comply with local fire codes and NFPA series standards. Automatic sprinkler systems shall cover all areas including guest room closets and bathrooms (concealed sprinklers). Kitchen areas shall be provided with kitchen-specific fire suppression systems (ANSUL or equivalent) covering exhaust hoods and ducts. Hilton particularly emphasizes redundant design of fire protection systems: fire pumps shall be powered by dual power supplies + emergency generators, with pump control panels located within the pump room.
HDDG Review and Brand Compliance Process
Hilton projects must undergo a strict HDDG review process to ensure brand standard implementation. Phase 1: Brand Compliance Review—conducted twice by Hilton Asia-Pacific Technical Services during the schematic design phase and construction document phase. The review is based on the HDDG compliance checklist with a total of 310 check items covering HVAC, electrical, plumbing, fire protection, and intelligent systems disciplines. Phase 2: Technical Design Review—a third-party engineering consultant designated by Hilton conducts detailed review of construction documents for all disciplines. Phase 3: Construction Coordination Inspection—Hilton's Director of Engineering or delegated representative conducts quarterly site inspections to confirm construction quality and equipment brands comply with HDDG requirements. Phase 4: Commissioning and Acceptance Testing—HVAC system air and water balancing, water system flow testing, BAS point-to-point testing, and fire linkage testing shall be documented in reports issued by qualified commissioning consultants. Key equipment brands must come from Hilton's Approved Brand List, including chillers (Trane, Carrier, or York—choose one of three), boilers (Clements or Fulton), and generator sets (Cummins or Caterpillar). Brand substitutions require submission of a substitute brand evaluation report for approval by Hilton's Vice President of Engineering.