Only system, 3 zones, not heating. High limit switch was stuck opened and not allowing heat to cycle completely. Reset switch and system works. Heat exchanger has some rusted and hot spots, blower wheel getting dirty and no in line switch. All zones are working properly. Also, draft inducer motor has high amperage (3.2 amps, shouldn’t be higher than 3.7 amps , by the label). System is 13 years old. Due to the be and conditions of the system, recommend to upgrade the system, with 10 years warranty, and WiFi thermostat. Sent estimates for potential repairs (not recommend). Set a lead to quote upgrading the only system for today.