View visual findings from this job here - https://visionshare.xoi.io/?id=XA-A243-7F77D842C73048E1996AE55476497739 Customer had an error message on their alarm system indicating smoke at HVAC 2: The fire department came yesterday morning, but we’re unable to find any issues while on site * at arrival inspected the units until I found that the back right unit was labeled HVAC 2 * these systems have external smoke alarms that are installed on the return duct work of the equipment outside * at arrival the system is on stand by set for 50, indoor temp 56 and the FAN ON * call for heating and test system operations- normal * check the indoor blower compartment- okay * shut the system down and preform powder cloud test on heat exchanger- no blow back- okay * call for heating again and cycle on and off- normal operations Inspected the smoke detector installed on the return duct work outside- these sensors often give false readings due to humidity and dust. When the screws were loosened