This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Measurement of Passenger Compartment Refrigerant Concentrations Under System Refrigerant Leakage Conditions
- Ground Vehicle Standard
- J2772_201909
- Revised
Downloadable datasets available
Annotation ability available
Sector:
Issuing Committee:
Language:
English
Scope
This Standard is restricted to refrigeration circuits that provide air-conditioning for the passenger compartments of passenger and commercial vehicles.
This Standard includes analytical and physical test procedures to evaluate refrigerant concentration inside the passenger compartment. In the early phases of vehicle evaluation, usage of the analytical approach may be sufficient without performing physical tests.
The physical test procedure involves releasing refrigerant from an external source to a location adjacent to the evaporator core (inside the HVAC module). An apparatus is used to provide a repeatable, calibrated leak rate. If the system has multiple evaporators, leakage could be simulated at any of the evaporator locations.
This standard gives detail information on the techniques for measuring R-744 (CO2) and R-1234yf (HFO-1234yf), but the general techniques described here can be used for other refrigerants as well.
Rationale
This standard is being updated to include references to the United States Environmental Protection Agency’s Significant New Alternatives Policy (SNAP) use restrictions with regard to R-744 and R-152a (now supported as a secondary loop application only). The standard was originally developed to provide a consistent method for measuring refrigerant concentrations in a motor vehicle to be used in conjunction with risk assessments that are done for new refrigerants being developed for mobile air conditioning systems. This standard has not been updated for heat pump systems that use an interior condenser for heating. Interior condensers may create a new risk associated with a high-pressure heat exchanger in the cabin interior air flow path. Manufacturers should appropriately consider additional risks associated with using an interior condenser heat exchanger.
Recommended Content
Ground Vehicle Standard | Standard for Refrigerant Risk Analysis for Mobile Air Conditioning Systems |
Ground Vehicle Standard | Safety Standards for Motor Vehicle Refrigerant Vapor Compression Systems |
Topic
Data Sets - Support Documents
Title | Description | Download |
---|---|---|
Unnamed Dataset 1 | ||
Table 1 | Typical vehicle interior volumes | |
Table 2 | Typical air exchange rates | |
Table 3 | Example of calculation for released refrigerant | |
Table 4 | Example test plan conditions | |
Table 5 | Refrigerant flow rates for different evaporator failure modes. | |
Table 6 | Typical refrigerant properties for R-744 and R-1234yf |
Issuing Committee
Interior Climate Control Vehicle OEM Committee
The Interior Climate Control OEM Committee is responsible for developing and maintaining SAE Standards, Recommended Practices, and Information Reports that serve as guidelines for technicians who service mobile air conditioning systems and operate refrigerant recycling equipment as it applies to automobiles, light trucks and other vehicles with similar R12 systems. Participants in the SAE Interior Climate Control Standards Committee include OEMs, suppliers, consulting firms, government, and other interested parties.
Reference
* Redlines comparisons are available for those standards
listed in the Revision History that contain a radio button. A
redline comparison of the current version against a revision is
accomplished by selecting the radio button next to the standard and
then selecting 'compare'. At this time, Redline versions only exist
for some AMS standards. SAE will continue to add redline versioning
with ongoing updates to SAE MOBILUS.