Air fryer runs but does not heat; fan operates and timer counts down, but food remains cold.

Safety first: Unplug the Klarstein air fryer and allow it to cool completely.

Steps:

• 1. Confirm no heat: Run a short cycle at maximum temperature for 3–5 minutes with an empty basket. Carefully feel for warm air at the exhaust. If completely cold, proceed.
• 2. Access heater and wiring: Remove the housing to expose the heating element, thermal fuse, and wiring harness.
• 3. Test thermal fuse and heater: With a multimeter, check continuity across the thermal fuse and then across the heating element. Replace any component that tests open.
• 4. Inspect wiring: Ensure all spade connectors are tight on the heater and thermal fuse. Replace any burned or loose connectors with high-temperature rated parts.
• 5. Check control board relay: If heater and fuse are good, inspect the heater relay on the control board for burn marks or cracked solder. Replace the control board if the relay is faulty.
• 6. Reassemble and test: Refit covers, plug in, and run a test cycle to confirm that heating is restored.

Warning: Do not bypass the thermal fuse to restore heat; this is a serious fire hazard.