GB 50243-2016 Code for Acceptance of Construction Quality of Ventilation and Air Conditioning Works

General Provisions

• 第 1.0.2 条This code applies to the acceptance of construction quality of ventilation and air conditioning works in buil…
• 第 1.0.3 条The requirements for construction quality acceptance set out in the engineering technical documents and contr…
• 第 1.0.4 条This specification shall be used in conjunction with the current national standard "Unified Standard for Cons…
• 第 1.0.5 条The acceptance of construction quality for ventilation and air conditioning works shall, in addition to compl…
• 第 3.0.1 条The acceptance of construction quality for ventilation and air conditioning works shall, in addition to compl…
• 第 3.0.3 条Major materials, finished products, semi finished products, accessories, and equipment used in the project sh…
• 第 3.0.4 条Ventilation and air conditioning works shall be constructed in accordance with the specified procedures, and …
• 第 3.0.5 条Before concealed works are covered up, the contractor shall notify the supervision unit and other relevant pa…
• 第 3.0.8 条At the completion acceptance of ventilation and air conditioning works, complete technical documentation of t…

Terminology

• 第 2.0.1 条Ventilation and air conditioning works : including supply air, exhaust air, smoke control and smoke exhaust s…
• 第 2.0.2 条Air duct : A conduit made of metal, non metal, or composite materials, used for conveying air.
• 第 2.0.3 条Duct system : A system composed of ducts, components, fittings, and connectors.
• 第 2.0.4 条Duct components : refers to air outlets, valves, hoods, cowls, silencers, access doors, test holes, etc.
• 第 2.0.5 条Duct fittings : refers to elbows, tees, crosses, reducers, square to round transitions, etc.
• 第 2.0.6 条Detachable air conditioning unit : refers to air conditioning equipment consisting of a refrigeration compres…
• 第 2.0.7 条Packaged air conditioning unit : An air conditioning device that assembles the refrigeration compressor, cond…
• 第 2.0.8 条Air handling unit (AHU) ：Air conditioning equipment assembled from various functional sections (such as mixin…
• 第 2.0.9 条Fresh air volume : The amount of fresh air supplied to a room per unit time.
• 第 2.0.10 条System airflow rate : The total volume of air delivered by a ventilation or air conditioning system per unit …
• 第 2.0.11 条Air leakage rate : The amount of air leaked from the duct system per unit time.
• 第 2.0.12 条Air leakage rate : The ratio of air leakage volume to system air volume.
• 第 2.0.13 条Duct strength : The ability of a duct to withstand the specified pressure without damage or excessive deforma…
• 第 2.0.14 条Duct stiffness : The ability of a duct to resist deformation.
• 第 2.0.15 条Duct tightness : The ability of a duct system to prevent air leakage under specified pressure.
• 第 2.0.16 条Duct system working pressure : The maximum static pressure value borne by the inner wall of the duct under no…
• 第 2.0.17 条Permissible air leakage of duct system : The maximum permissible air leakage under the working pressure of th…
• 第 2.0.18 条Duct system air leakage test : A test of the airtightness performance of the duct system.
• 第 2.0.19 条Ductwork system strength test : A test to verify the ductwork system's ability to withstand working pressure.
• 第 2.0.20 条Duct system airtightness test : Testing the sealing performance of the duct system.
• 第 2.0.21 条Duct System Air Leakage Test Apparatus : Equipment used to measure the air leakage rate of duct systems.
• 第 2.0.22 条Ductwork system strength test apparatus : Equipment used to measure the strength of a ductwork system.
• 第 2.0.23 条Duct System Airtightness Test Apparatus : Equipment used to measure the airtightness of a duct system.
• 第 2.0.24 条Duct system air leakage test methods : including positive pressure testing and negative pressure testing.
• 第 2.0.25 条Ductwork system strength test methods : including static pressure testing and dynamic pressure testing.
• 第 2.0.26 条Ductwork system airtightness test methods : including the light leak method and the air leakage rate method.
• 第 2.0.27 条Duct system air leakage test results : expressed as leakage air volume or leakage rate.
• 第 2.0.28 条Ductwork system strength test results : Indicated by whether the ductwork sustains damage or excessive deform…
• 第 2.0.29 条Duct system airtightness test results : Indicated by whether the duct system meets the allowable air leakage …
• 第 2.0.30 条Duct System Air Leakage Test Report : A document recording the test process and results.
• 第 2.0.31 条Duct System Strength Test Report : A document recording the test process and results.
• 第 2.0.32 条Duct System Airtightness Test Report : A document recording the test process and results.
• 第 2.0.33 条Duct System Air Leakage Test Record : A table for recording test data.
• 第 2.0.34 条Duct system strength test record : A table recording test data.
• 第 2.0.35 条Duct System Airtightness Test Record : A table for recording test data.
• 第 2.0.36 条Duct system air leakage test instruments : such as air leakage testers, micro manometers, etc.
• 第 2.0.37 条Duct system strength testing instruments : such as pressure gauges, strain gauges, etc.
• 第 2.0.38 条Ductwork system airtightness testing instruments : such as light leak detectors, air leakage testers, etc.
• 第 2.0.39 条Ductwork system air leakage test personnel : should have received professional training and possess the corre…
• 第 2.0.40 条Ductwork system strength test personnel : should have received professional training and possess the correspo…
• 第 2.0.41 条Ductwork system airtightness test personnel : should have received professional training and possess the corr…
• 第 2.0.42 条Ductwork system air leakage test environment : The test shall be conducted under no wind or light wind condit…
• 第 2.0.43 条Duct system strength test environment : The test should be conducted under conditions with no or minimal vibr…
• 第 2.0.44 条Duct system tightness test environment : should be conducted under no wind or light wind conditions.
• 第 2.0.45 条Duct system air leakage test safety : Relevant safety operating procedures shall be followed.
• 第 2.0.46 条Ductwork system strength test safety : Relevant safety operating procedures shall be followed.
• 第 2.0.47 条Ductwork system airtightness test safety : Relevant safety operating procedures shall be followed.
• 第 2.0.48 条Duct system air leakage test standard : shall comply with the provisions of this code and relevant standards.
• 第 2.0.49 条Duct system strength test standard : shall comply with the provisions of this code and relevant standards.
• 第 2.0.50 条Duct system airtightness test standard : shall comply with the provisions of this code and relevant standards.
• 第 2.0.9 条2. The terms themselves do not constitute acceptance "clauses," but they are the foundation for understanding…
• 第 2.0.16 条3. In hotel buildings, functional areas such as guest rooms, lobbies, restaurants, and meeting rooms have rel…

Basic Requirements

• 第 3.0.2 条Construction enterprises undertaking ventilation and air conditioning projects shall hold the corresponding q…
• 第 3.0.6 条Pipes and equipment in ventilation and air conditioning works shall be insulated and protected against corros…
• 第 3.0.7 条Finished product protection should be carried out properly during construction. In hotel construction, instal…

Duct fabrication

• 第 4.1.3 条Duct material requirements : Hotel ducts shall be made of non combustible materials (e.g., galvanized steel s…
• 第 4.1.4 条Fire damper installation : Fire dampers with a nominal actuation temperature of 70℃ must be installed where d…
• 第 4.2.1 条Steel duct thickness : Guest room supply air ducts (low pressure system) steel plate thickness ≥0.5mm; public…
• 第 4.2.3 条Duct sealing requirements : Joints and flange connections of hotel air conditioning ducts (medium pressure sy…
• 第 4.2.5 条Duct reinforcement : Hotel ducts with a side length ≥630mm (e.g., main ducts in the lobby and banquet hall) m…
• 第 4.2.7 条Duct flange connection : For hotel ducts, the flange bolt spacing shall be ≤150 mm (medium and high pressure …
• 第 4.3.1 条Duct cleaning and protection : After hotel ducts are fabricated, their interiors must be clean, free of oil a…
• 第 4.3.4 条Flexible short duct : A flexible short duct of 150–300 mm in length shall be installed at the connection betw…
• 第 4.3.7 条Duct supports and hangers : Spacing of duct supports and hangers in hotels: for horizontal installation, ≤4 m…

Duct components

• 第 6.2.1 条The material, specifications, and model of duct components (such as control valves, silencers, fire dampers, …
• 第 6.2.4 条The blades of the multi leaf control damper shall fit tightly, be evenly spaced, and adjust flexibly. When us…
• 第 6.2.8 条Duct access doors (inspection doors) shall open and close smoothly and tightly; when used on ducts within hot…
• 第 6.2.9 条The installation elevation and position of duct components (such as valves and air outlets) shall meet the de…

Air duct components

• 第 6.2.2 条Fire dampers and smoke exhaust valves (outlets) must comply with fire protection product standards, and their…
• 第 6.2.3 条The material of explosion proof air valves must comply with the design requirements; in environments with exp…
• 第 6.2.5 条Silencers and acoustic elbows shall be fabricated and installed with smooth, undamaged surfaces; the infill m…
• 第 6.2.6 条Air diffusers shall be installed in the correct position and securely, with tight connections to the ductwork…
• 第 6.2.7 条Flexible short ducts (e.g., at fan to duct connections) shall be made of corrosion resistant, moisture proof,…

Ductwork system installation

• 第 6.2.1 条Before duct installation, debris inside and outside the duct shall be removed, and cleaning and protection sh…
• 第 6.2.2 条Duct connections must not be installed within walls or floor slabs, and supports and hangers must not be loca…
• 第 6.2.3 条The connection interface between the duct and the brick or concrete flue shall be inserted in the direction o…
• 第 6.2.4 条When an air duct passes through a fire rated or explosion proof wall or floor slab that requires enclosure, a…
• 第 6.3.1 条The spacing of duct supports and hangers shall comply with the requirements: for horizontal installation, whe…
• 第 6.3.2 条Air duct connections shall be tight and secure; flange gasket material shall meet the system function require…
• 第 6.3.3 条During duct installation, supports and hangers should not be located at air outlets, valves, access doors or …
• 第 6.3.4 条When ducts pass through deformation joints, flexible connections shall be used and compensation devices shall…
• 第 6.3.5 条Flexible short ducts shall be installed at the connections between air ducts and equipment such as fans and a…
• 第 6.3.6 条After the duct system is installed, tightness testing shall be carried out according to the system category. …
• 第 6.3.7 条After the duct system is installed, duct air leakage testing shall be carried out (20% sampling for medium pr…
• 第 6.3.8 条Permissible deviation for duct installation: levelness ≤3‰, total deviation ≤20 mm; verticality ≤2‰, total de…
• 第 6.2.5 条2. In hotel buildings, the installation of smoke control systems (such as pressurized air supply to corridors…
• 第 6.3.9 条3. Due to grease and high temperatures in the kitchen exhaust system, the installation of its ductwork requir…

Ventilation and air-conditioning equipment installation

• 第 7.2.1 条Before equipment installation, verify the model, specifications, and parameters, and check that the appearanc…
• 第 7.2.2 条The dimensions, positions, elevations and anchor bolt hole locations of equipment foundations (such as fans a…
• 第 7.2.3 条Fan installation: Vibration isolators (e.g., springs, rubber) should be uniformly loaded, and flexible short …
• 第 7.2.4 条AHU installation (including fresh air handling units and air handling units): independent foundations shall b…
• 第 7.2.5 条Fan coil unit installation: allowable levelness deviation ≤3‰; flexible connections shall be used for connect…
• 第 7.2.6 条VAV terminal unit installation: independent supports and hangers shall be provided; connections to air ducts …
• 第 7.2.7 条VRF outdoor unit installation: vibration isolation pads shall be provided; ventilation and heat dissipation c…
• 第 7.2.8 条VRF indoor unit installation: shall be level (permissible deviation ≤1‰), condensate pipe slope ≥8‰, and elec…
• 第 7.2.9 条Air purification equipment (e.g., guest room fresh air purification units) installation: independent maintena…
• 第 7.2.10 条Silencer installation: independent supports and hangers shall be provided; connections to air ducts shall be …
• 第 7.2.11 条Installation of smoke exhaust fans (for hotel corridors and stairwells): vibration isolation devices shall be…
• 第 7.2.12 条Equipment and pipe connections: Flexible short pipes shall not be used as load bearing components for alignme…
• 第 7.2.13 条Equipment trial run: Fans, AHUs, etc. shall run continuously for 2 h, with bearing temperature rise ≤40℃ and …

Air-conditioning cooling system

• 第 8.1.3 条The installation location, foundation elevation, and vibration isolation measures of refrigeration equipment …
• 第 8.2.1 条The installation deviation of refrigeration units (including modular units) shall comply with the standard: a…
• 第 8.2.2 条When connecting chillers to piping, do not force the connections to align; flexible connectors (such as rubbe…
• 第 8.3.1 条Cooling towers shall be installed in a well ventilated location, with a clearance of no less than 1.0 m betwe…
• 第 8.3.2 条The allowable installation levelness deviation of the cooling tower shall not exceed 5/1000 (i.e., ≤5 mm devi…
• 第 8.4.1 条The pipe materials, fittings, and valve models, specifications, and pressure ratings of refrigeration system …
• 第 8.4.3 条When refrigerant system pipes are welded or flange connected, the welds shall be free of defects such as crac…
• 第 8.5.1 条Refrigeration system valves shall be installed in the correct position and orientation, and shall be accessib…
• 第 8.6.1 条After the refrigeration system is installed, system blow down (purge with dry compressed air or nitrogen at 0…
• 第 8.6.2 条Refrigeration system vacuum test: evacuate the system to an absolute pressure ≤0.1kPa (or a vacuum degree ≥ 0…
• 第 8.6.3 条When charging the refrigeration system with refrigerant, charging shall be carried out according to the speci…
• 第 8.7.1 条Refrigeration system trial run: it shall be carried out after the individual trial runs of equipment such as …
• 第 8.7.2 条During the combined trial run of the refrigeration system, check whether each protective device (such as high…
• 第 8.1.3 条Hotel buildings have high requirements for noise and vibration control , so clause (vibration isolation measu…
• 第 8.6.1 条Clause ~8.6.3 (blow down, airtightness, and vacuum tests) is key to the safe operation of the refrigeration s…

Air-conditioning water system

• 第 9.1.2 条Material and equipment incoming inspection : The specifications, models, and performance parameters of pipes,…
• 第 9.2.1 条Pipe installation slope : The installation slope of air conditioning water system pipes (especially condensat…
• 第 9.2.3 条Pipe connections : Galvanized steel pipes shall use threaded or grooved connections; seamless steel pipes and…
• 第 9.2.5 条Valve installation : Valves shall undergo strength and tightness tests before installation. Valves installed …
• 第 9.2.7 条Expansion joint installation : Expansion joints (e.g., bellows expansion joints, square expansion joints) sha…
• 第 9.2.9 条Pipe supports and hangers : The type, material, spacing and installation position of pipe supports and hanger…
• 第 9.3.1 条Hydraulic pressure test : After the air conditioning water system is installed, a hydraulic pressure test mus…
• 第 9.3.2 条Flushing and Water Quality : After the system passes the pressure test, the system shall be flushed until the…
• 第 9.3.3 条Condensate system water filling test : After the condensate piping installation is completed, a water flow te…
• 第 9.4.1 条Insulation installation : The thickness and material of the insulation layer for air conditioning water pipes…
• 第 9.4.3 条Insulation joints : Insulation joints shall be tight and bonded with dedicated tape or adhesive. At valves, f…
• 第 9.2.1 条Hotel guest room areas (such as fan coil units and condensate water systems) have extremely high requirements…

Anti-corrosion and insulation

• 第 10.1.2 条The combustion performance grade of insulation materials and their auxiliary materials (such as adhesives and…
• 第 10.1.3 条When thermal insulation materials arrive on site, verify test reports for thickness, density, thermal conduct…
• 第 10.2.1 条During the installation of thermal insulation for ducts and air conditioning equipment, the insulation shall …
• 第 10.2.2 条When the duct insulation layer is fixed with insulation pins, the number of insulation pins shall meet the re…
• 第 10.2.3 条Joints of duct insulation must be tight and flat. When using rolled material, the lap width shall not be less…
• 第 10.2.4 条The insulation layer at duct flange locations shall be treated separately, with a thickness not less than 80%…
• 第 10.2.5 条During the installation of thermal insulation for air conditioning water pipes and refrigerant pipes, the gap…
• 第 10.2.6 条When pipe insulation uses pipe shells, the longitudinal seams of the shells shall be staggered and firmly adh…
• 第 10.2.7 条Insulation at pipe accessories such as valves, filters, flanges and metal hoses shall be installed separately…
• 第 10.2.8 条A vapor barrier (e.g., aluminum foil, FRP) shall be provided on the outer surface of the insulation layer; th…
• 第 10.2.9 条A protective layer (such as metal sheeting, FRP, etc.) shall be provided over the outdoor pipe insulation. Th…
• 第 10.3.1 条The type, color, and number of coats of anti corrosion paint shall comply with the design requirements. Befor…
• 第 10.3.2 条Before applying anti corrosion coating, sheet steel ducts shall undergo rust removal. Unless required by desi…
• 第 10.3.3 条Anti corrosion coatings on pipe and equipment surfaces shall be uniform, free from missed spots, runs, peelin…
• 第 10.3.4 条Metal components such as supports and hangers and fasteners shall be treated for corrosion protection (e.g., …
• 第 11.2.1 条After system commissioning is completed, the temperature and humidity, airflow velocity and noise level of ai…
• 第 10.2.1 条2. In hotel buildings, anti condensation (Clauses 10.2.4 and 10.2.8) and fire protection (Clause 10.1.2) are …

System commissioning

• 第 11.2.1 条Before system commissioning, confirm that individual equipment trial runs have passed and that ductwork, wate…
• 第 11.2.2 条For major equipment such as fans, pumps, and chillers, the single machine trial run shall be continuous for n…
• 第 11.2.3 条For terminal equipment such as fan coil units and fresh air handling units, the individual trial run shall be…
• 第 11.3.1 条The system air volume commissioning result shall not deviate from the design air volume by more than 10%. For…
• 第 11.3.2 条The measured total system air volume shall not deviate from the design air volume by more than 5% or +10%. Fo…
• 第 11.3.3 条The deviation between the measured air volume of each air outlet (supply, return, exhaust) and the design air…
• 第 11.4.1 条The total flow of the air conditioning water system (chilled water, cooling water) shall not deviate from the…
• 第 11.4.2 条The flow deviation of each loop in the air conditioning water system (such as different floors and different …
• 第 11.5.1 条The system joint trial run shall operate continuously for no less than 8 hours, with all equipment, piping, v…
• 第 11.5.2 条During the combined system trial run, the indoor temperature, relative humidity, airflow velocity and noise l…
• 第 11.5.3 条For the linkage commissioning of smoke control systems (such as hotel corridors and stairwell vestibules), it…

Completion acceptance

• 第 11.0.2 条Before the completion acceptance of ventilation and air conditioning works, the combined trial operation and …
• 第 11.0.3 条At completion acceptance, the following documents and records shall be checked:<br 1. Drawing review records,…
• 第 11.0.4 条The visual quality inspection shall include the following items, with key focus on hotel engineering:<br 1. A…
• 第 11.0.5 条Upon completion acceptance of ventilation and air conditioning works, system energy efficiency performance te…
• 第 11.0.6 条The completion acceptance of ventilation and air conditioning works shall be organized by the construction un…
• 第 11.0.7 条Completion acceptance shall be qualified, and acceptance documents shall be produced. For hotels, particular …

Engineering reference only — verify against project conditions and the latest codes.