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Gas Fitting
Gasfitter Red Seal Certification
Testing, Leak Detection & Commissioning
Knowledge Check
Testing, Leak Detection & Commissioning
Knowledge Check
Knowledge Check
1 / 9
What does a CO reading above 100 ppm air-free in flue gas indicate?
A
Excellent efficiency
B
Good air-to-gas ratio
C
Incomplete combustion requiring service
D
Normal operation
Check Answer
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