In short
A Koolmore dryer running cold is usually telling you its exhaust is blocked. Start with the duct behind the machine crushed against the wall, then work outward along the duct to the outside flap. Only when the air path is clear does an element or a thermostat become the suspect.
Symptoms, including the misleading ones
- The vent flap outside does not open when it runs — No airflow at the outside terminal, which means the blockage is somewhere between the drum and the wall.
- Clothes are warm but still damp after a full cycle — Heat is present but moisture is not leaving, which points squarely at airflow rather than heating.
- 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.
Causes on a Koolmore dryer, likeliest first
- The duct behind the machine crushed against the wall — Everything the dryer takes out of the clothes has to leave through the duct. A run that is long, kinked, or packed with lint holds that moisture in, so the clothes stay damp while the machine runs hot inside its own cabinet. It comes first for a practical reason: the check takes minutes and it decides which half of this list you need. This is foodservice-grade equipment, which changes the order: what is cleaned daily fails from cleaning, and what is run constantly fails from running.
- The drum turning on one supply leg with no heat — An electric dryer takes a large-appliance circuit: the motor and the controls run from part of it, while the heating element needs the whole supply. Lose one side at the breaker or the outlet and you get a machine that tumbles perfectly and never warms. It sits second: less common than the one above, but still ahead of anything that needs a meter.
- 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. Third, and only worth attention once the two above are clean.
- The element open-circuit, or an igniter that no longer lights — 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. At the foot of the list, on likelihood alone.
Where to look, and in what order
- Pull the machine out and look at the duct behind it — A crushed or disconnected duct is visible immediately and explains everything on this page. Start here — it is free, and it decides which half of the list you are in.
- Note whether the machine has ever heated since it was installed or moved — A machine that has never heated in a new position points at the supply or the outlet rather than at a part. Follow with this: it either confirms the second cause or clears it for good.
- Look down into the filter housing with a torch — A mat of lint below the screen restricts the machine just as effectively as a blocked duct. Last of the owner-side checks; anything past it belongs to a technician.
The steps, with tools and times
- Disconnect the duct and clear it along its whole run, then refit it without kinks — Leave the machine far enough forward that the duct is not crushed when it goes back.
Tools: vacuum, duct brush, screwdriverAbout 60 min
- Cycle the dryer breaker fully off and on, then test a short cycle — If heat returns, the supply was the fault; if it trips again, stop and call an electrician.
About 15 min
- Wash the lint screen in hot soapy water, dry it, and refit it — Do this whenever water will not pass straight through the mesh; it is the single most neglected job on a dryer.
Tools: hot water, brushAbout 20 min
- STOP HERE if the next step needs a meter on live terminals — That is the line between an owner check and a service call, and it is not a line worth crossing for a fault that is already narrowed to two causes.
The safety part
Safety
Unplug the dryer or switch off its breaker before any panel comes off — a large-appliance circuit is behind that panel and it is not a place to guess. Never run the machine without its lint filter in place, and leave the door switch wired as the factory ran it: a drum that can turn with the door open is a hazard.
Where the owner fix ends
Book a visit when the air path is clear, the breaker has been cycled and there is still no heat. Call an electrician instead if the breaker trips when the machine runs, or if the machine has never heated in this position.
Where to go next
Generalized information
Scope of this page: Koolmore dryers generally, not one family. Model-specific information — wiring colours, part numbers, resistance and torque figures — belongs on the page for that family, and where such a page exists it outranks this one.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
