CAME OUT FOR AN ESTIMATE ON A AIR DUCT CLEANING SYSTEM. INSTALLED SIAQ 4223 PREM ADC ERSA, *2 6 DROP CEILING GRILLS. MADE SURE EQUIPMENT WAS INSTALLED PROPERLY, AND WORK AREA WAS CLEAN WHEN FINISH. CHECK THERMOSTAT, AIRFLOW, AIR FILTER, AND ALL ELECTRICAL CONNECTIONS, EVERYTHING IS RUNNING GOOD.