What should be monitored closely during a worst-case CAZ de-pressurization test?

During a worst-case CAZ (Combustion Appliance Zone) depressurization test, the primary focus is on accurately monitoring the CAZ pressure levels. This test is designed to evaluate how the appliance reacts under extreme conditions, particularly when negative pressure is created in the CAZ.

Maintaining proper CAZ pressure is crucial because it can directly affect the safe operation of combustion appliances. If the pressure levels drop too low during the test, it can lead to backdrafting, where products of combustion are drawn from the appliance into the living space instead of being vented outside, posing serious safety hazards. Monitoring these pressure levels helps ensure that the appliance is functioning properly and that harmful gases are not entering the home.

Other aspects, like ductwork condition, appliance operating temperature, and fuel consumption, while important in other contexts, do not provide the immediate safety information that CAZ pressure levels do in a worst-case scenario assessment.