When measuring for baseline in the combustion appliance zone (CAZ), should the CAZ door be open or closed?

The correct approach to measuring for baseline in the combustion appliance zone (CAZ) is to have the CAZ door closed. This practice ensures that you are capturing accurate data regarding the air pressure and combustion efficiency in a controlled environment, as an open door would allow an influx of outside air, potentially skewing the results.

By measuring with the door closed, you are able to understand how the CAZ behaves under normal operating conditions—reflecting how appliances would operate during typical scenarios without external influences. This is critical for assessing the performance and safety of combustion appliances, since fluctuations in air pressure can impact their operation, leading to issues such as backdrafting or incomplete combustion.

Measuring with the door closed helps ensure consistent and reliable data, which is vital for proper analysis and subsequent recommendations regarding safety and efficiency improvements for the systems in question.