Furnace precision tune up; clean and tune up furnace; clean burners, test ignition components, adjust gas level, test safety circuit, check indoor motors, checked all electrical components, tested indoor air flow, checked heating temperatures, and tested overall furnace operation. Found that main flame safety and ignitor are failing. Big components will cause furnace not to operate of they fail. Inducer motor is making high pitched winding sound. This is due to bearing failure. This puts motor at much higher risk of failure. Blower motor starter is failing which can lead to damage of the larger blower in lower furnace cabinet. Due high costs of repairs, age and current condition of furnace, I do encourage replacement. AC precision tune up. Clean and tune up AC; cleaned condenser coil, checked all outdoor electrical components, tested indoor air flow, checked refrigerant levels, and tested overall AC operation. Ac is low on refrigerant charge. This will cause excessive run times