GB/T 21361-2017 PDF in English
GB/T 21361-2017 (GB/T21361-2017, GBT 21361-2017, GBT21361-2017)
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GB/T 21361-2017: PDF in English (GBT 21361-2017) GB/T 21361-2017
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 27.200
J 73
Replacing GB/T 21361-2008
Motor Vehicle Air-conditioning Unit
ISSUED ON. JULY 12, 2017
IMPLEMENTED ON. FEBRUARY 1, 2018
Issued by. General Administration of Quality Supervision, Inspection and
Quarantine;
Standardization Administration of the People’s Republic of
China.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative References ... 4
3 Terms and Definitions ... 5
4 Models and Basic Parameters ... 7
5 Requirements... 8
6 Test Methods ... 12
7 Inspection Rules ... 18
8 Marking, Packaging, Transportation and Storage ... 19
Appendix A (Normative) Test Method of Refrigerating Capacity of Air
Conditioning Unit ... 22
Appendix B (Normative) Test Method of Noise of Air Conditioning Unit ... 36
Appendix C (Normative) Test Method of Vibration of Air Conditioning Unit ... 42
Appendix D (Informative) Test Method of Refrigerating Capacity of Air
Conditioning Unit on the Site of Usage ... 45
Foreword
This Standard is drafted in accordance with stipulations in GB/T 1.1-2009.
This Standard serves as a replacement of GB/T 21361-2008 Motor Vehicle Air-
conditioning Unit. In comparison with GB/T 21361-2008, there are the following main
technical changes.
---The definition of refrigeration coefficient of performance is added (please refer
to 3.10);
---The requirements of radio disturbance characteristics and air quality are added
(please refer to 5.2);
---The requirement of operation test is modified (please refer to 5.5.2);
---The requirement of airtightness is modified (please refer to 5.5.1);
---The requirement of noise is modified (please refer to 5.5.10);
---The requirement of measuring grounding resistance is deleted (please refer to
5.6.4.3);
---The method of measuring the refrigerating capacity of motor vehicle air-
conditioning unit on the scene of usage is added (please refer to Appendix D).
This Standard was proposed by China Machinery Industry Federation.
This Standard shall be under the jurisdiction of National Technical Committee (238) on
Refrigeratory Equipment of Standardization Administration of China (SAC/TC 238).
The responsible drafting organizations of this Standard. Hefei General Machinery &
Electrical Products Inspection Institute, Shanghai SONGZ Automobile Air Conditioning
Co., Ltd., Hefei General Machinery Research Institute.
The participating drafting organizations of this Standard. Zhejiang Dun’an Artificial
Environment Co., Ltd., Nanjing Aotecar New Energy Technology Co., Ltd., EMERSON
Climate Technologies (Suzhou) Co., Ltd., Guangzhou JYAC Automobile Air
Conditioner, Suzhou Xin Tong Chuang Automobile Air Conditioning Co., Ltd., Zhejiang
Chunhui Industrial Group.
The main drafters of this Standard. Rongye, Qinfeng, Xie Hongxi, Cai Peiyu, Chen
Xiangji, Liuqiang, Ouyang Yong, Pengfei, Yang Chenguang, Wu Weixin.
The release of previous versions of the standard replaced by this Standard is as follows.
---GB/T 21361-2008.
Motor Vehicle Air-conditioning Unit
1 Scope
This Standard specifies the terms, definitions, models, basic parameters, requirements,
test methods, inspection rules, marking, packaging, transportation and storage of
motor vehicle air-conditioning unit (hereinafter referred to as “air-conditioning unit”).
This Standard is applicable to motor vehicle air-conditioning unit for the purpose of
refrigeration.
NOTE. please refer to GB/T 3730.1 for the definition of motor vehicle.
2 Normative References
The following documents are indispensable to the application of this Standard. In terms
of references with a specified date, only versions with a specified date are applicable
to this Standard. The latest version (including all the modifications) of references
without a specified date is also applicable to this Standard.
GB/T 191 Packaging Pictorial Markings for Handling of Goods
GB/T 3785.1-2010 Electroacoustics - Sound Level Meters - Part 1. Specifications
GB 4706.32 Safety of Household and Similar Electrical Appliances - Particular
Requirements for Heat Pumps, Air-conditioner and Dehumidifier
GB 5226.1 Electrical Safety of Machinery - Electrical Equipment of Machines -
Part 1. General Requirements
GB/T 6388 Transport Package Shipping Mark
GB 8410 Flammability of Automotive Interior Materials
GB 9237-2001 Mechanical Refrigerating Systems Used for Cooling and Heating -
Safety Requirements
GB/T 13306 Plates
GB/T 18655 Vehicles, Boats and Internal Combustion Engines - Radio
Disturbance Characteristics - Limits and Methods of Measurement for the
Protection of On-board Receivers
GB/T 27630 Guideline for Air Quality Assessment of Passenger Car
JB/T 7249 Terminology of Refrigeration Equipment
SAE J 1627-1995 Performance Criteria for Electronic Refrigerant Leak Detectors
SAE J 1628 Technician Procedure for Using Electronic Refrigerant Leak Detectors
for Service of Mobile Air-conditioning Systems
3 Terms and Definitions
What is defined in JB/T 7249, and the following terms and definitions are applicable to
this document.
3.1 Motor Vehicle Air-conditioning Unit
Motor vehicle air-conditioning unit refers to an air-conditioning system that is
constituted of compressor, condenser, throttle element, evaporator, draught fan and
necessary control units. It is adopted to adjust the interior temperature and humidity in
motor vehicle and provide comfortable environment to passengers.
3.2 Indirect Drive Air-conditioning Unit
Indirect drive air-conditioning unit refers to air-conditioning unit whose compressor is
driven by an independent auxiliary power.
3.3 Direct Drive Air-conditioning Unit
Direct drive air-conditioning unit refers to air-conditioning unit whose compressor is
driven by motor vehicle’s main power.
3.4 Air Enthalpy Difference
Air enthalpy difference refers to a method of measuring air conditioning unit’s capacity.
It measures air conditioning unit’s air supply parameter, air return parameter and
circulating air volume; determines air conditioning unit’s refrigerating capacity through
the product of air volume, air supply and air return enthalpy difference.
3.5 Refrigerating Capacity
Refrigerating capacity refers to the heat that air conditioning unit drains away from
enclosed space, interior space or area of motor vehicle under stipulated refrigerating
capacity and test conditions.
NOTE. the unit of refrigerating capacity is (W).
3.6 Air Flow Rate
Air flow rate refers to the volume flow rate of air that enters air conditioning unit within
a unit time under stipulated refrigerating capacity and test conditions.
NOTE. the unit of air flow rate is (m3/h).
3.7 Compressor Drive Power
Compressor drive power refers to the power consumed by driving the compressor
under stipulated refrigerating capacity and test conditions.
NOTE. the unit of compressor drive power is (W).
3.8 Accessory Electric Power
Accessory electric power refers to the total power of evaporator fan, condenser fan,
electromagnetic clutch and electronic control system of air conditioning unit under
stipulated refrigerating capacity and test conditions.
NOTE. the unit of auxiliary power consumption is (W).
3.9 Energy Efficiency Ratio; EER
Energy efficiency ratio refers to the ratio of air conditioning unit’s refrigerating capacity
to the compressor drive power under stipulated refrigerating capacity and test
conditions.
NOTE. the unit of energy efficiency ratio is (W/W).
3.10 Refrigeration Coefficient of Performance; REER
Refrigeration coefficient of performance refers to the ratio of air conditioning unit’s
refrigerating capacity to the compressor drive power under stipulated engine speed.
Refrigeration coefficient of performance shall be calculated in accordance with
Formula (1).
Where,
---the ratio of air conditioning unit’s refrigerating capacity to the compressor
drive power at a low engine speed;
---the ratio of air conditioning unit’s refrigerating capacity to the compressor
drive power at a nominal refrigerating engine speed;
---the ratio of air conditioning unit’s refrigerating capacity to the compressor
drive power at a high engine speed.
NOTE. the unit of refrigeration coefficient of performance is (W/W).
4 Models and Basic Parameters
4.1 Models
4.1.1 In accordance with the drive mode of refrigerating compressor, it can be divided
into.
---Indirect drive;
---Direct drive.
4.1.2 In accordance with structural model of motor vehicle air conditioning unit, it can
be divided into.
---Integral type;
---Split type.
4.1.3 In accordance with the evaporator’s layout mode of motor vehicle air conditioning
unit, it can be divided into.
---Overhead type;
---Rear type;
---Bottom type;
---Internal type.
4.1.4 In accordance with the air supply mode of motor vehicle air conditioning unit, it
can be divided into.
---Direct air supply type;
---Air flue type.
4.2 Basic Parameters
4.2.1 The basic parameters of air conditioning unit include. refrigerating capacity, air
flow rate, compressor drive power, accessory electric power and noise.
4.2.2 In terms of air conditioning unit without connection with air hose, external static
pressure shall be 0 Pa. Air condition unit with connection with air hose shall adopt
nominal external static pressure.
5 Requirements
5.1 General Requirements
5.1.1 Air conditioning unit shall comply with the stipulation in this Standard; air
conditioning unit shall be manufactured in accordance with drawings and technical
documents that are approved through a stipulated procedure.
5.1.2 The surface of painted parts shall not manifest obvious bubbles, flow marks,
leakage, exposed primer, and unexpected wrinkles or damages.
5.2 Requirements of Components and Materials
5.2.1 All the components and materials of air conditioning unit shall respectively
comply with the stipulation in relevant standards; satisfy the requirements of functional
performance and guarantee the safety.
5.2.2 The heat insulation layer of air conditioning unit shall manifest satisfying heat
retaining property and non-absorbency; it shall be non-toxic and odorless. Its
combustion characteristic shall comply with the stipulation of technical requirements in
GB 8410. The heat insulation layer shall be firmly and evenly pasted.
5.2.3 The selection and installation of electrical components of air conditioning unit
shall comply with the requirement in GB 4706.32 and GB 5226.1, and the requirement
of radio disturbance characteristic of GB/T 18655.
5.2.4 The external insulation layer of wires and cables used in air conditioning unit
shall adopt anti-flaming, low-smoke and halogen-free materials. The current-carrying
capacity of wires and cables shall satisfy the operating requirements.
5.2.5 The quality of air supply from the evaporator shall comply with the requirement
of air quality in GB/T 27630.
5.3 Structural Requirements
5.3.1 The drainage structure of air conditioning unit shall be reliable. During the
operation, condensation water and raindrops shall not leak into the car. The air outlet
of air conditioning unit shall not spray with water.
5.3.2 The opening size of fresh air outlet of air conditioning unit shall comply with the
requirement of fresh air volume. The fresh air outlet shall be equipped with the function
of air-water separation, which can prevent raindrops or snow from entering the car
during the operation. The filter screen shall be conveniently assembled and
disassembled.
5.4 Requirements of Assembly
5.4.1 Before assembly, the various components of the refrigerating system of air
conditioning unit shall be clean and dry.
5.4.2 The various pipelines and components in air conditioning unit shall adopt
necessary positioning measures to guarantee that there is no failure caused by
vibration, impact, or the affect of heat or cold during the operation.
5.4.3 The connection of various components of air conditioning unit shall be firm; there
shall be no leakage of water or oil.
5.4.4 The installation and layout of electrical circuits, electrical equipment and self-
control devices shall be safe, firm and reliable.
5.5 Performance Requirements
5.5.1 Air-tightness
The test shall be conducted in accordance with Method a) in 6.3.1 or Method b) in
6.3.1.
a) When Method a) in 6.3.1 is adopted in the test, the assembly of the evaporator
and the condenser shall not manifest any leakage;
b) When Method b) in 6.3.1 is adopted in the test, the annual leakage rate of the
assembly of the evaporator and the condenser after helium leak detection shall
be lower than 5 g/a.
5.5.2 Operation
When the test is conducted in accordance with the method in 6.3.2, the assembly of
the evaporator and the condenser shall be able to function normally. The safety
protection device shall be sensitive and reliable; the motion of control components,
such as temperature and electrical appliances, shall be normal. All the test items shall
comply with the requirement in design.
5.5.3 Waterproof property
When the test is conducted in accordance with the method in 6.3.3, the seam joint
where the air conditioning unit is connected with car body shall not manifest any water
leakage.
5.5.4 Refrigerating capacity
When the test is conducted in accordance with the method in 6.3.4, the practically
tested refrigerating capacity of air conditioning unit shall be not less than 95% of the
nominal refrigerating capacity.
5.5.5 Compressor drive power
When the test is conducted in accordance with the method in 6.3.6, the practically
tested power of the compressor of air conditioning unit shall be not more than 110% of
the nominal compressor drive power.
5.5.6 Accessory electric power
When the test is conducted in accordance with the method in 6.3.4, the practically
tested accessory electric power of air conditioning unit shall be not more than 110% of
the nominal accessory electric power.
5.5.7 Refrigerating operation under maximum load
Refrigerating operation of the air conditioning unit under the maximum load shall satisfy
the following requirements.
a) After the test is conducted in accordance with the method stipulated in 6.3.7,
the various components of the air conditioning unit shall not be damaged and
shall be functioning normally;
b) In the first 1 h of continuous operation, the air conditioning unit shall be able to
function normally;
c) After re-starting the air conditioning unit after 3 min of suspension, within the
first 5 min after it starts operation, the overload protector is allowed to be tripped
off. However, no motion is allowed after that. If the overload protector is not
reset within the first 5 min after it starts operation and is reset within 30 min
after it is suspended, the air conditioning unit shall be operated continuously for
1 h.
5.5.8 Condensation operation
The air conditioning unit shall be able to operate normally under the working condition
of condensation. The condensation water shall not be blown out of the air conditioning
unit with the wind, instead, it shall be smoothly drained out of the drain hole (pipe).
5.5.9 Low-temperature operation
The air conditioning unit shall be able to operate normally under the working condition
of low temperature. The air flue of the evaporator shall not be blocked by frost. The air
outlet of the air conditioning unit shall not blow out flake ice or waterdrops.
5.5.10 Noise
The noise (sound pressure level) of the evaporator’s side of the air conditioning unit
shall be tested in accordance with the method in 6.3.10; the tested value shall not
exceed 70 dB(A). In the test of noise (sound pressure level) of the condenser’s side of
the air conditioning unit, the tested value shall not exceed 70 dB(A).
5.5.11 Air flow rate
The air flow rate of the air conditioning unit under practical air condition shall be tested
in accordance with the method in 6.3.5; the value of air flow rate shall not be less than
95% of the nominal air flow rate.
5.5.12 Energy efficiency ratio
The practically tested value of energy efficiency ratio of the air conditioning unit shall
be not less than 95% of the indicated value, and not less than 1.9 W/W.
5.5.13 Refrigeration coefficient of performance
The practically tested value of refrigeration coefficient of performance of the air
conditioning unit shall be not less than 95% of the indicated value, and not less than
2.0 W/W.
5.5.14 Vibration resistance property
After vibration test, the compressor, evaporator and condenser of the air conditioning
unit shall not manifest any breakage, crack or leakage. Components shall not be
damaged; fasteners shall not be loosened; the property shall comply with the
requirement.
5.6 Safety Requirements
5.6.1 Safety of refrigerating system
The property of the refrigerating system or refrigerating components of the air
conditioning unit shall comply with the stipulation of strength test in 5.1.1.1 and system-
wide test in 5.1.1.2 in GB 9237-2001.
5.6.2 Safety property of control devices
The air conditioning unit shall be equipped with safety protection measures or devices
that prevent the operating parameters (such as temperature and pressure, etc.) from
exceeding the stipulated range. The setting of the protection devices shall comply with
design requirements and be sensible and reliable.
5.6.3 Mechanical safety
The design of the air conditioning unit shall guarantee reliable stability during normal
transportation, installation and usage. The air conditioning unit shall have sufficient
mechanical strength; its structure shall guarantee that in the vibration test in
accordance with the method in 6.3.11 and the normal operation of motor vehicle, its
components will not be damaged, the fasteners will not be loosened, and the property
can comply with the requirement. After the vibration test, air-tightness test shall be
conducted; it shall be guaranteed that there is no leakage. Protective cover, protective
net or similar components shall have sufficient mechanical strength.
5.6.4 Electrical safety performance
5.6.4.1 Insulation resistance
The test shall be conducted in accordance with the method that is stipulated in 6.3.12.1.
The insulation resistance of the air conditioning unit’s live parts against non-charged
metal parts shall be not less than 2 MΩ.
5.6.4.2 Electrical strength
The test shall be conducted in accordance with the method that is stipulated in 6.3.12.2.
Impose the stipulated test voltage between the air conditioning unit’s live parts and the
non-charged metal parts for 1 min, there shall be no breakdown or flashover.
5.6.4.3 Ground connection
The air conditioning unit shall have reliable ground connection with obvious marking.
5.6.4.4 Safety signs
The air conditioning unit shall set up permanent safety signs (such as signs of ground
connection and warning, etc.) in obvious positions.
6 Test Methods
6.1 Test Conditions
6.1.1 Please refer to Appendix A for the test device of air conditioning unit.
6.1.2 The working condition of the test shall comply with the stipulation in Table 1.
Table 1 -- Working Condition
Unit. °C
Test Condition
Refrigerating
Operation
Nominal
Refrigeration
Maximum Load
Low Temperature
Condensation
Dry-bulb
Temperature
Dry-bulb
Temperature
Wet-bulb
Temperature
Wet-bulb
Temperature
Air Condition of Side Entrance of
Evaporator
Air Condition of Side Entrance of
Condenser
6.1.3 The speed of the compressor shall comply with the stipulation in Table 2.
Table 2 -- Compressor Speed
Unit. /min
6.1.4 The motor terminal voltage for the draught fan shall comply with the stipulation
in Table 3.
Table 3 -- Relations between Nominal Voltage and Terminal Voltage
Unit. V
6.1.5 The flow rate of the air inlet of the condenser shall satisfy the following
requirements.
a) When the condenser is installed on the windward side, it shall comply with the
stipulation in Table 4, but if the condenser is equipped with a draught fan, the
draught fan shall be shut down.
Model
Compressor Speed
Low Speed Nominal Refrigerating Speed High Speed
High Speed
Direct Drive
Indirect Drive
Vortex
Spiral
Swash Plate Piston
Crank Connecting
Rod Piston
NOTE 1. in principle, the refrigerating capacity of main engine drive type refers to the refrigerating capacity when
the compressor speed is the nominal refrigerating speed. When there is significant difference between the
compressor speed of 40 km/h common speed and the nominal refrigerating speed, then, compressor speed,
which is at the common speed, signifies the refrigerating capacity, but the compressor speed shall be indicated.
NOTE 2. during the test, the variation of the compressor speed shall be less than or equal to ± 2%.
Nominal Voltage Terminal Voltage
Table 4 -- Flow Rate of Air Inlet
Unit. m/s
b) When the condenser is installed on a side other than the windward side, the
motor-driven condenser draught fan shall be tested in accordance with the
terminal voltage in Table 3.
c) In terms of integral independent air conditioning unit, the flow rate of the air inlet
when the auxiliary engine reaches the nominal speed shall be considered as
the flow rate of the air inlet of the condenser.
6.1.6 The model and accuracy of the instruments and apparatuses shall comply with
the stipulation in Table 5.
Table 5 -- Model and Accuracy of Instruments and Apparatuses
Compressor Speed
Low Speed
Nominal Refrigerating Speed
High Speed
Flow Rate of Condenser’s Air Inlet
Category Model Accuracy
Temperature Meter
Air Pressure Meter
Electric Meter
Refrigerant Pressure Meter
Pressure Meter (atmospheric
pressure)
Speed Meter
Mass Meter Measured Mass
Measured Speed
Atmospheric Pressure
Reading
Air Duct Static
Pressure
Air Temperature
Refrigerant
Temperature
Mercury Glass Thermometer
Resistance Thermometer
Thermocouple
Temperature Sensor
Barometer, Air Pressure Transmitter
Pressure Gauge, Pressure
Transmitter
Indicative
Integrating
Pressure Gauge, Pressure
Transmitter
Tachometer, Strobe
6.1.7 In the refrigerating test of the air conditioning unit under nominal working
condition, the allowable deviation of the reading of various parameters shall comply
with the stipulation in Table 6.
Table 6 -- Allowable Deviation of Reading under Nominal Working Condition
6.1.8 In the test (other than nominal working condition) of the air conditioning unit, the
allowable deviation of various parameters of working condition shall comply with the
stipulation in Table 7.
Table 7 -- Allowable Deviation of Reading in Property Test
Unit. °C
6.2 General Requirements
6.2.1 All the tests of the air conditioning unit shall comply with the nominal voltage and
nominal frequency on the plate.
6.2.2 In terms of the split type of air conditioning unit, the pipe that connects the indoor
unit and the outdoor unit shall be tested in accordance with the full length or 10 m pipe
provided by the manufacturer. The length of the outdoor part of the connecting pipe
shall be not less than 3 m; the thermal insulation and installation requirements of the
outdoor part shall comply with the product specification.
6.3 Test Methods
6.3.1 Air-tightness test
Item
Air Temperature
/°C
Dry Bulb
Wet Bulb
Voltage /V
Air Volume Flow /(m3/h)
External Resistance of Air Flow/Air
Static Pressure/Pa
Deviation of Average Reading to
Nominal Working Condition
Maximum Deviation of Various Readings
to Nominal Working Condition
Item
Maximum Range of Variation
Average Range of Variation
Dry-bulb Temperature of Indoor and
Outdoor Air
Wet-bulb Temperature of Indoor and
Outdoor Air
Air-tightness test includes the following two methods.
a) Under the normal charging amount of refrigerant, the assembly of the
evaporator and the condenser shall satisfy the technical requirement
regarding R134a in SAE J 1627-1995. In terms of testable components whose
leak rate is 14 g/a, use an electronic refrigerant leak detector to conduct the
test in accordance with the operating procedure that is stipulated in SAE J
1628.
b) Charge dry nitrogen into the assembly of the evaporator and the condenser, till
it reaches the maximum pressure of unit operation, then, immediately seal it up.
6.3.2 Operation test
Test the operative condition of the assembly of the evaporator and the condenser; the
sensitivity and reliability of safety protection devices. Test whether the motion of control
components, such as temperature and electrical appliances, is normal.
6.3.3 Spraying test
When the air conditioning unit is installed on a finished motor vehicle, evenly spray not
less than 200 mm/h precipitation whose pressure is higher than 0.1 MPa onto
corresponding parts of the finished motor vehicle. The test shall last for not less than
10 min.
6.3.4 Refrigerating capacity test
Conduct the test in accordance with the nominal static pressure of air outlet of air
conditioning unit; the nominal refrigerating capacity test condition that is stipulated in
6.1; the method in Appendix A.
6.3.5 Air flow rate test
Test the air flow rate of the air conditioning unit simultaneously in the test of the
refrigerating capacity in accordance with the test method provided in Appendix A.
6.3.6 Compressor drive power and accessory electric power test
Test the compressor drive power and accessory electric power of the air conditioning
unit simultaneously in the test of the refrigerating capacity in accordance with the test
method provided in Appendix A.
6.3.7 Test of refrigerating operation under maximum load
Stably operate the air conditioning unit under the test condition of maximum load that
is stipulated in 6.1, then, shut it down for 3 min; re-start it and operate it for 1 h.
6.3.8 Test under condensation operation
Continuously operate the air conditioning unit for 4 h under the test condition of
condensation operation that is stipulated in 6.1.
6.3.9 Test under low-temperature operation
Continuously operate the air conditioning unit for 4 h under the test condition of low
temperature that is stipulated in 6.1
6.3.10 Noise test
Under nominal voltage and nominal frequency, test the noise of the air conditioning
unit in accordance with the stipulation in Appendix B.
6.3.11 Vibration test
Conduct the vibration test of the air conditioning unit in accordance with the stipulation
in Appendix C.
6.3.12 Test of safety property of electrical appliance
6.3.12.1 Test of insulation resistance
Use megohmmeter to test the insulation resistance of live parts of the air conditioning
unit against non-charged metal parts. The scale of the megohmmeter shall comply with
the stipulation in Table 8.
Table 8 -- Megohmmeter Scale
6.3.12.2 Test of electrical strength
Conduct the test of electrical strength of the air conditioning unit in accordance with
the test ......
...... Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
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