Regulations & SafetyQuestion 66 of 240
Which practice is safest when pressure-testing a system for leaks?
a.Use regulated dry nitrogen, and never use oxygen or compressed air with refrigerant present
b.Use pure oxygen for a stronger test
c.Pressurize with acetylene for faster results
d.Use the refrigerant charge itself at maximum pressure
Explanation
Leak testing should be done with regulated dry nitrogen because it is inert and will not react, and oxygen or acetylene must never be used since they can cause a violent reaction or explosion in the presence of oil or refrigerant. Compressed air can introduce moisture and, mixed with refrigerant under heat, form combustible conditions. Always use a pressure regulator so the system is not over-pressurized.
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