Air pressure measurement to detect an obstruction in an airflow path

An aerosol-generating system comprising:

• a heater assembly for heating an aerosol-forming substrate;
• a power supply;
• an airflow path defined between an air inlet and an air outlet, the airflow path passing through the heater assembly;
• at least one sensor for sensing an airflow property of air in the airflow path;
• and
• electric circuitry comprising a memory and connected to the heater assembly and to the power supply, the electric circuitry being configured to measure a plurality of values associated with the airflow property during the course of a plurality of user puffs based on signals from the at least one sensor, determine an average of values from the plurality of values, and to compare this average of values with a predetermined value;
• wherein the electric circuitry is configured to detect an obstruction in the airflow path based on the comparison and is configured to limit the power supplied to the heater assembly if an obstruction is detected until the obstruction has been removed.