What is the recommended concentration of carbon monoxide (CO) in flue gasses for most heating and water heating appliances?

The recommended concentration of carbon monoxide (CO) in flue gasses for most heating and water heating appliances is 50-100 ppm. This range is deemed acceptable because it balances safety and operational efficiency.

Carbon monoxide is a colorless, odorless gas that can be harmful or even fatal at elevated levels. Therefore, monitoring and maintaining CO levels within this specified range helps ensure that appliances are functioning properly and are safe for use. Operating within these limits allows for effective combustion while minimizing the risk of CO accumulation, which can lead to dangerous situations for occupants.

Concentrations outside this range indicate potential operational problems, either from incomplete combustion or malfunctioning equipment. Higher levels (e.g., in the 100-150 ppm or 150-200 ppm ranges) could suggest that there’s a blockage, improper installation, or maintenance issue that needs addressing to maintain safety and efficiency. Thus, adhering to the recommended level of 50-100 ppm is crucial for safe appliance operation and compliance with safety standards.