Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
Current economizers cannot provide zero outdoor airflow when the damper is closed, and economizers cannot provide 100% outdoor airflow when the damper is fully open due to uncontrolled damper leakage and perimeter gap leakage. Typical closed economizer damper outdoor airflow without sealed perimeter gap is 10 to 25% and maximum outdoor airflow is 55 to 80%. If the perimeter gap is sealed per US Patent 9,671,125 or patents pending, then the uncontrolled perimeter gap leakage will be 5 to 10% due to damper leakage. Low leakage dampers will have lower leakage, but cannot prevent perimeter gap leakage. Most economizer controllers cannot provide the required minimum outdoor airflow per ASHRAE 62.1 due to economizer actuators not being calibrated per US 10,001,289 and patents pending.
