F33 appears; washer-dryer may not heat water or may stop during heating phase.

Safety first: Unplug the unit and allow time for any hot components to cool.

• Access heater: Remove the rear panel and locate the wash heater at the base of the tub.
• Test heater element: Disconnect the heater wires and measure resistance across the terminals. If open (OL) or far from spec, replace the heater.
• Check thermal cutoff and thermostats: Test any inline thermal devices for continuity. Replace any that are open.
• Inspect wiring: Ensure all heater connections are tight and free of burns or corrosion.
• Control relay: If heater and wiring are good, the heater relay on the main control may be faulty. Replace the control board if indicated by diagnostics.