Performed annual heating maintenance loomis, client signed up for one system. Client has 3 split systems, 2 under the house, 1 in attic. Silver flex ducts sealed units 12-13 yrs old. Rheem split systems under house, one 80% furnace, one 90% furnace. Tested systems, working at this time. Client has 5 filters due to be changed. 2x20-25-1, 2x14-25-1, 14-14-1. 3x tstats ok. Cycled system, running ok at this time. Recommend annual maintenance. Cleaned burners and flame sensor on 90 % unit under home, tested parts ok for now. Due to age of equipment recommend keeping up on maintenance. Might even look into washable filters, so you don’t have to buy 5 at a time. Tested system safety features, working correctly at this time. Ran system for 30 mins no faults ok for now. Signing back up for another year for all 3 systems, With washable filters x5. Client will call when filters arrive, for me to install filters.