"John Phillips" wrote
A fault I have seen on two washer-dryers (not your model, though) is in
the condenser/filter box (not sure what it is really called) on the
outlet as the outlet hose exits the case.

This box fills with lint, scale and other resudues over time. The air
and water flow during drying gradually reduces. Eventually the overheat
thermostat on the heater/blower operates and drying fails. If the
overheat themostat is self-resetting, drying failure is intermittent.

Thank you John, will check!

Steve