Performed fall Maintenance. Cycled system for heat. Verified proper heating sequence of operations. Temperature rise across heat exchanger is within range. Blower wheel and evap coil are clean. Ducts are all properly sealed. Tested and verified heating components are working properly. Merv 16 filter is dirty and should be replaced. Replaced with homeowner approval. Washed out electric cleaner on back house filtration system. Wiped down heating components and burner compartment. Whole home Air purifier is fully operational and working accordingly. This home now has 2 systems, homeowner is aware membership needs to be upgraded to a 2 system, office to call and make the adjustment. Cycled system, system is fully operational upon departure.