What should be done to annular spaces around penetrations for vents and combustion air intake pipes?

Permanently sealing the annular spaces around penetrations for vents and combustion air intake pipes is essential for safety and efficiency. These spaces can act as pathways for air leaks, which may compromise the performance of the ventilation system. By sealing these spaces, you ensure that there is no unintended air infiltration, which can lead to improper combustion, safety hazards, and energy losses.

Sealing these areas also helps prevent the entry of moisture, pests, and other contaminants, which could affect the integrity of the gas equipment and the overall functioning of the system. This practice aligns with safety codes and standards that require secure installation of venting systems to maintain the efficacy and safety of propane applications.

Other options, such as covering with insulation or leaving open for airflow, do not address the potential hazards associated with unsealed penetrations. Temporarily blocking is not a permanent solution and could lead to the same issues as leaving the openings unsealed. Therefore, permanently sealing the penetrations is the most effective and safest approach.