Chimney Safety Institute of America (CSIA) Certification Practice Test

What temperature above their dew point is expected for Category I gas appliances?

1. 100 degrees

2. 140 degrees

3. 180 degrees

4. 200 degrees

The correct answer is: 140 degrees

For Category I gas appliances, the standard requires that the flue gas temperature be maintained at least 140 degrees Fahrenheit above the dew point. This is critical because it helps prevent condensation within the venting system. When flue gas cools below its dew point, the moisture in the gas can condense and potentially lead to corrosive damage in the venting materials, reduced efficiency, and a higher risk of chimney blockages or failures. Maintaining the flue gas temperature sufficiently above the dew point ensures that the exhaust gases remain in a vapor state, minimizing the risks associated with moisture buildup. This temperature threshold is an essential part of ensuring safe and efficient operation of these appliances.