02-05-21, Performed the fall maintenance on two gas furnaces. I poured bleach down the primary drain to the upstairs unit for Mr. McDonald. Both systems are functioning within manufacture specs and no issues recorded at this time. All safeties are working, flue pipes are secure, Gas lines are tight, flames are blue, all safeties working, units are sealed properly, both blower capacitor’s are good, all wires are secured. Both systems have a good temperature rise. Both filters need to be replaced. Mr. McDonald said he will pick up filters today and have them installed. Returned both thermostats back to normal setting. Thank you for giving us the opportunity to serve you.