The short answer
Expect lint choking the airflow before it has left the drum first. Owners reach for the heating element, but on a machine of this kind the element is well down the list — and fitting one into a blocked vent simply destroys the new part too.
What you observe
- The cycle takes far longer than it used to — A gradual increase in drying time is the earliest sign of a duct that is slowly closing up.
- It heats at first and then goes cold partway through — A safety thermostat is opening as the machine overheats, which is airflow again rather than an element.
- The outside of the machine is hot to the touch — Heat that cannot leave through the duct stays in the cabinet, which is a warning rather than a curiosity.
- NEAR MISS — you can smell gas near the machine — If you smell gas: do not switch anything on or off, leave the building, and call the gas utility or the emergency number from outside. Do not look for the leak yourself.
What actually causes this, ranked
- Lint choking the airflow before it has left the drum — Lint also gets past the screen into the housing below it, and that housing is rarely cleaned. It packs solid over years and produces exactly the same slow-drying, no-heat complaint as a blocked duct. First, because nothing else on the list explains as many of these calls, and ruling it out costs nothing but a few minutes. With a badge of this size the sensible order is the one that gets you to an answer without waiting on a part that may take weeks to arrive.
- The protection circuit tripped by a hot cabinet — It ranks here because it explains the symptom completely, and because it is the bridge between the free airflow checks above it and the parts below it. Second, because it produces the same complaint from the other side and is still an owner-side check.
- Half the electrical supply lost on an electric dryer — It belongs on the list because the fix may be at the consumer unit rather than in the appliance, and because no part inside the dryer will ever correct it. It belongs at this point because by now the field has narrowed and the remaining checks cost more time.
- A gas valve or flame sensor not proving the flame — Electric dryers heat with a coil element that eventually burns through; gas dryers light a burner with an igniter and a flame sensor, and any of those three can fail. In both cases the drum turns and the air stays cold. Bottom of the order, because reaching it means the three likelier answers were already wrong.
Check in this order, and why
- Take the lint screen out and hold it up to the light, then run water on it — Water that beads or sits on the mesh rather than running straight through means a softener film is sealing it. First: the answer here changes everything you do next.
- Ask whether the heat stopped suddenly rather than fading over weeks — A device that opens does so in one moment; a duct blocks gradually. The history separates them. Then this — it is the next cheapest thing that can be wrong.
- Switch the breaker for the dryer fully off and back on — A double breaker can trip on one side and still look closed, which is exactly the condition that produces this fault. Leave this one until the cheap checks are done; it is the slowest of the three.
What you can do yourself
- Vacuum the filter housing as deep as the nozzle will reach — Power off first, and take the hose right down into the slot rather than skimming the top.
Tools: vacuum, torchAbout 25 min
- Note when the heat stopped and what the load was — An overloaded machine on a long run of duct is the usual history behind an opened fuse.
About 10 min
- Have the outlet checked by an electrician if heat never returns — This is electrical work at a high-current outlet and it is not an owner test.
About 10 min
- STOP if the fault is now down to a sealed or high-voltage part — Those need tools, training and a discharge procedure. Write down what you found and hand it over.
Before you touch anything
Safety
Isolate the machine at the breaker before removing a panel, and never reach into a drum with the power available. If you smell gas near a gas dryer: do not switch anything on or off, leave the building, and call the gas utility or the emergency number from outside. Do not look for the leak yourself.
When to hand it over
Stop and call at the point where a panel has to come off. If you smell gas at any point, leave the building and call the gas utility or the emergency number from outside before doing anything else.
Pages next to this one
What this page does not cover
This is the generalized page for KTN dryers. If a page exists for your particular family or model line, it is linked from this section and it outranks this one for your unit. What is deliberately absent: part numbers, connector pinouts and the service-manual sequences, which are family-specific and wrong the moment they are generalized.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
