On February 6th 2020 at 22:42 hrs, Station 18 Folsom Fire Company was dispatched to 1818 5th ave for a CO alarm. Upon the arrival of ENG 18 it was found to be a 20 yr old CO alarm sounding. Crew entered with a gas meter, no readings found. Homeowner advised to replace CO alarm, the company was inservice for 15 minutes under the command of Deputy Chief Scott Kreamer.