The wash is faultless, but at the end of a drying programme the load comes out warm and still damp, sometimes wetter round the seams.
Usually: Almost always the condensing side rather than the heat: a condenser channel furred with scale and fibre, or the small cold-water valve and gauze that feed it silted up so no spray reaches the duct.
On the visit: We run a drying cycle and watch for water actually entering the condenser channel, then strip the duct, descale it, clean the valve gauze and confirm the spray is landing where it should before we look at anything else.
The drying cycle runs for hours on an automatic programme and only stops when it is cancelled by hand, or it restarts as soon as it seems finished.
Usually: The humidity or conductivity sensor in the drum reading wrongly, a drifting drying thermistor, or restricted airflow that means the machine genuinely never reaches its dry threshold.
On the visit: We clean the sensor contacts, meter the sensor and thermistor against their proper values, run a timed dry alongside an automatic one to see which finishes, and check the whole air path for a restriction.
The drum turns during drying and the programme counts down normally, but the air coming off the door is cold and the load is untouched.
Usually: An open-circuit drying element, a one-shot thermal cut-out that has tripped after a lint restriction, or the relay on the board that feeds the heater failing to pull in.
On the visit: We meter the element and both cut-outs cold, then check for supply at the heater on a live drying cycle. If a cut-out has tripped we find what made it trip, because fitting a new one without clearing the restriction only buys a few weeks.
A whine, rattle or drumming noise that only ever happens on the drying part of the cycle, sometimes with a hot, dusty smell.
Usually: The drying fan impeller packed with fluff, a foreign object in the fan housing, or a worn fan motor bearing dragging so the airflow drops away.
On the visit: We take the fan housing off, clear the impeller and the duct behind it, turn the fan by hand to feel the bearing and run the motor under power. A worn motor is renewed; a fluffed impeller usually just needs clearing properly.
The machine stops part way through drying with a drain fault, or there is water sitting in the drum when the drying programme should be running.
Usually: The condensing water has nowhere to go. Both halves of the machine share one sump and one drain pump, so a filter full of fibre or a stalled impeller stops the dry as surely as it stops the wash.
On the visit: We strip the filter, sump and drain pump, clear the impeller by hand, check the hose run behind the machine, then run a drying cycle and stand there to confirm the condensing water is leaving properly.
Clothes come out of the wash far wetter than they used to, and the drying programme cannot catch up no matter how long it runs.
Usually: A spin problem, not a drying problem: worn carbon brushes, a slack or shredded belt, a silted pressure chamber leaving the machine unsure of the water level, or the load unbalanced so it never reaches full speed.
On the visit: We watch a full spin from cold, check brushes and belt, clear the pressure hose and chamber, and confirm the machine is reaching its rated speed. Fix the spin and the drying time usually falls back to something sensible.
The power to the kitchen trips out within a minute or two of the drying part of the cycle starting, while the wash runs through with no trouble.
Usually: The drying element or its harness gone down to earth, normally where moisture and fibre have collected around the heater housing, or a wire chafed through against the duct.
On the visit: We isolate the machine, insulation test the element and the heater wiring separately from the rest of the appliance, inspect the harness where it passes the duct, and renew whichever one fails the test rather than both.