Dryer function will not heat; display shows F15 during drying cycles.

Safety first: Unplug the combo and allow the dryer section to cool completely.

• Access dryer heater: Remove rear panel or side panel (model dependent) to locate the dryer heater housing and thermostats.
• Check wiring: Inspect heater terminals and wiring harness for burns or loose connections. Repair as needed.
• Test thermal fuse and thermostats: Using a multimeter, check continuity of the thermal fuse and high-limit thermostat mounted on the heater duct. Replace any open components with JennAir-specified parts.
• Test heater element: Measure resistance across the heater element. An open reading indicates a failed element that must be replaced.
• Reassemble and test: After replacing faulty parts, run a timed dry cycle and verify that the drum heats and F15 does not return.

When to call a technician: If all heater components test good, the control board heater relay or wiring may be at fault and should be checked professionally.