HVAC Journeyman Practice Exam

Sediment traps in fuel-gas lines are not required for which of the following?

1. Hydronic boilers

2. Gas fireplaces

3. Residential furnaces

4. Commercial furnaces

The correct answer is: Hydronic boilers

Sediment traps in fuel-gas lines serve the purpose of capturing debris and impurities from the gas supply, which helps prevent these contaminants from entering and damaging gas-powered appliances. They are particularly important in systems where gas flow can carry debris, which could affect proper operation and safety. Hydronic boilers, in particular, do not typically require sediment traps because these systems are designed to operate with water rather than direct combustion from gas. The water acts as a medium that can prevent debris from causing operational issues, and the way hydronic systems are set up does not lend itself to the same risks associated with gas combustion appliances that are more sensitive to impurities. Gas fireplaces, residential furnaces, and commercial furnaces, on the other hand, are combustion appliances that can be adversely affected by debris in the gas line. Therefore, sediment traps are beneficial in those systems to ensure reliability, efficiency, and safety during operation. This distinction highlights the unique requirements of hydronic boilers compared to other gas appliances, justifying the lack of a necessity for sediment traps in their installations.