SAE J2791:2019 download free.HFC-134a Refriqerant Electronic Leak Detectors , Minimum Performance Criteria.
The purpose of this SAE Standard is to establish minimum performance criteria for a modern class of electronic probe- type leak detectors intended for use in automotive air conditioning systems with HFC-134a refrigerant.
1. SCOPE
SAE J2791 provides testing and functional requirements to meet specified minimum performance criteria for electronic probe-type leak detectors. So they will identify smaller refrigerant leaks when servicing all motor vehicle air conditioning systems, including those engineered with improved sealing and smaller refrigerant charges to address environmental concerns and increase system efficiency. SAE J2791 does not address any safety issues concerning their design or use.
2. REFERENCES
2.1 Applicable Documents
The following publication forms a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply.
3. GENERAL DESCRIPTION AND OPERATING INSTRUCTIONS
31 The detector abel be suitable lot use In an automotive service garage and operate r ambient temperatures of IS to
49’C (59 to 120’F).
3.2 The detector shalt have at least three scales that can be manually selected: (1) 4 g/yr (0.15 oz?): (2) 7g/i (0,25 ozlyr); (3)14 g/,i- (0.5 ozl).
It shall be tested to meet the performance specifications of the standard by a qualified Independent laboratory. The laboratory shall maintain all documentation related to its testing. sicluding calibration and maintenance data for its equipment, for a period of five iesrs folloving the test of the specific detector.
3.3 If it passes, the detector shall carry a label that states ‘Desagn certified by (name of testing laboratory) to meet SAE J2791 with lettering in bold lace type at least 3mm high
3.4 If it does not pass, the detector may be retested subject to the limits of Section 10. ha detector fails beyond these retest bmits, it may be retested only after the marketer has documented changes made to correct the failure and given the data to the testing laboratory, A detector must pass the procedures in SectIons 7 and 8. A failure In either or both of those sections requires a complete retest. The detector also must meet the requirements of Section 9. passing the no-false-triggering requirement for transmission oil and engine oil (Nos. 14 and 15) and clearing withEi 20 seconds after a permitted false-tngger.
4. WHAT MUST ACCOMPANY THE DETECTOR
41 The marketing company shad provide operating instructions for the detedor that cover calbration, operating instructions and mstntenance. ricludrig replacement of any sensors, filters or power suppty
42 Tools, adapters and needed adjustment and cahtiration devices (irduding calibration and/or reference bottles) for the detector must be included with the detector.
4.3 The marketing company shad provide alt needed safety information arid labeling.
4.4 The marketing company shall provide the Section 9 list of all common ixider hood chemicals that may affect the operation of an electronic leak detector and indicate by V. if its detector will false-trigger from exposure to each of the chemicals on the list, or N lit will not false.trlgger
4.5 The resistance to false triggering shall be based on the test procedures described in Section 9. False triggering is defined as the detector making the same or similar indication (sound and/or tight) as if it detected a refrigerant leak.
5. REQUIRED BASIC FUNCTIONS
5.1 The detector may self-caabrate or require manual calibration, but once calibrated for an operation, It must hold that calibration br a time sufficient to perform the operations described in Sections 7 and 8 (Including 8.1 to 8.6). The does not preclude automatic recalibration far a probe that has been inserted into a contaminated atmosphere (as per Section 8). readlustment of sensitivity by operator selection, or an audible-and-or-visual warning of a condition beyond the operating scope at Its desige. The taller must be obviously different from the Indication of a refrigerant leak, although the same functional trigger may be used. Example: a steady liddcalor light vs. a flashing indicator light.
5.2 The detector must demonstrate automotive garage durability by continuing to function normally after being dropped
12 m (4.011) to a hard surface, such as a concrete floor. lor.v times. This test may be performed with the detector in
a protective caddy, provided the caddy is a standard part of the basic detector kit, and does not affect in-shop use of
the detector, or testing of the detector under all procedures In Sections 7.8.9 and 10.
The manufacturer of the detector shall explain lithe operating lnsthjctlons that if the detector takes longer than tao seconds to clear as a result of exposure to one of the ctienhicals in this section (up to the lest limit of 20 seconds), this indicates the probe apparently has encountered a large sample of contaminant. not necessanly a refrigerant leak. The instructions should add that the test area should be inspected for one of the permitted chemicals on the false-trigger list.
1. Windshield washer solvent (methanol base). Pois rib a beaker or petit dish,
2. Ford spot and stain remover (F3AZ-19521-WA). Pour into a beaker or petit dish.
3. Ford rust penetrant and wihdstor (F2AZ.19A501-A). Spray from aerosol onto a dish surface. until there is a bquld accumulation.
4. Ford gasket and mm adhesrve (F3AZ-196508-AA) Unthread and remove cap with brush holding a thick film ci the liquid for test.
5. Permatex Natural Blue cleaner and degreaser (biodegradable, non-caustic, with no dilonnated solvent, no petroleum advent, no phosphate). Pour into a beaker or petit dish.
6. Ford brake pails cleaner (F6A.Z-2C410.A5) Spray from aerosol onto a dish surface, until there Is a liquid accumulation.
7. Ford dear silicone rubber (F7AZ-19554-CA). Extrude bead 50mm (2.0 ii) or longer onto a dish sUrface.
6. Mcitcrcraft 0-05 anti-freeze/coolant. Pour into a beaker or petri dish. Heat to 150 to 180 F (66 to 82 C).
9. Gunk Liquid Wrench. Pour into a beaker or petit dish,
10. Ford Pumice/lotion hand cleaner (petroleum distillate, alcohol). Extrude from container onto a dish.
11. Ford Motorcraft DOT3 brake fluid. Pour fluid Into beaker or petit dish.
12. Ford Spray Carburetor Tune-Up Cleaner (D9AZ-l957-AA). Spray fran, aerosol onto a dish surface, until there is a liquid accumulation.
13. Ford silicone lubncant (COAZ.19553-AA) Extrude bead 50mm (2.0 In) or longer onto dish surface
14. Dexron automatic transmission fluid healed to 150 to 180 F(66 to 82 C). Pour Into a beaker or petn dish.
15. Mineral engine oil heated to 150 to 180 F (66 to 82 C). Pour into a beaker or petit dish.
10. REPEATING A TEST PROCEDURE AFTER A FAILURE
If a detector fails only one 10-sweep test, but passes all the other sweep tests, that one procedure may be repeated once. However, if it fails a second time, the entire test must be repeated. but not until the rnaitceter has provided documentation to the lest facility of changes made to the detector.
If a detector fails more than one 10-sweep test. it may repeat the entire lest procedure once. If it fails to pass a second time, it may not be retested until the marketer has provided documentation to the test facility of changes made Ia the detector.
If a detector passes all the sweep tests, but fats a false-tnggenng test (either by false.tflggeitng on engine or transmlsston oil, or by faang Ia clear front another chemical fates tflgger within 20 seconds), it may be retested against that chemical again, only at the conclusion of all other tests. If it falls a second time it may not be retested until the marketer has provided documentation to the test facility of changes made to the detector.