What H5 Means
WHICH MACHINES THIS APPLIES TO: H5 appears in the documentation for both the TL751 XXLW and the TLS752 XXL family. The two Asko documents word it differently and this page keeps them apart rather than merging them, because they are not the same sentence.
TL751 XXLW SERVICE MANUAL - WHAT H5 MEANS: the error-mode section gives H5 as "Heater overheated", and defines the trigger precisely: it is reported "when the temp sensor indicates 185 F (85 C) or higher". So this is not an inference from a cut-out operating. The control is reading an actual temperature and acting on the number.
TLS752 XXL OWNER MANUAL - WHAT H5 MEANS: the operating instructions print H5 as "Heater temperature control problem", and the printed instruction is to contact customer care rather than to try anything.
WHY BOTH WORDINGS ARE GIVEN: they are compatible readings of the same error at different levels of detail, and there is no Asko document that combines them into one definition. The service manual describes what the control measured; the owner manual describes what the owner should conclude, which is that the temperature control has not done its job and the machine should be looked at.
WHAT ACTUALLY HAPPENS INSIDE THE MACHINE: the heater is meant to cycle on and off under the control of the temperature sensor, holding the air in a band. If the air keeps climbing past that band, either the heat is not being switched off when it should be, or the air is not carrying the heat away. The first is an electrical problem - a relay welded closed, a control that has lost its sensor - and the second is almost always airflow: a blinded lint filter, a packed exhaust duct, a closed outside flap.
WHY THIS PAGE CARRIES A HIGHER SEVERITY: the machine is reporting a measured over-temperature in a cabinet that contains lint. That is the specific combination that makes dryers a fire risk, and it is why nothing on this page suggests running another load to see whether it repeats.
HOW THE MACHINE TELLS YOU: the service manual records that the unit buzzes for ten seconds every ten minutes while an error stands, and that the error display goes off when the power is switched off and on. The display clearing does not mean the temperature behavior has changed.
CLASSIFICATION: problem, and the one in the H-series with a real hazard behind it.
Common Causes of H5
- Lint filter blinded by fabric softener film or packed with lint
- Exhaust duct crushed, sagging, packed with lint or blocked at the outside flap
- Heater relay welded or stuck closed so the heat is never switched off
- Temperature sensor reading low, so the control keeps calling for heat that is already there
- Blower wheel loose, damaged or obstructed so air is not moving through the drum
- Machine installed with no clearance at its air intake
🔧 One Safe Check You Can Try
Stop using the dryer, switch it off at the wall socket or the breaker, and let it cool right down before touching anything. Then do the airflow work, because restricted airflow is the most common way a heater ends up above its band. Take the lint filter out, peel the lint off, wash the mesh under a tap to clear the fabric softener film that blocks air invisibly, and dry it fully before refitting. Follow the exhaust duct along its whole length for a crushed section, a sagging flexible run that has collected lint at its low point, or a blocked outlet at the wall, and check that the flap outside actually opens when the machine runs. Look at the lint that comes out: a heavy gray mat rather than loose fluff means the duct has been restricted for a long time. Having done all that, the decision is not whether the dryer feels better but whether the code returns, and the safest way to find out is with someone qualified present rather than by running loads unattended. If the machine reports H5 again with a clean filter and a clear duct, leave it switched off. At that point the heat is not being switched off when it should be, and that is inside the machine.
⚠ Why You Shouldn't Go Further Than That
- The machine has measured an over-temperature, so it is switched off at the breaker and left to cool completely before the filter housing, the duct or anything else is handled.
- The heater, its relay and its cut-outs sit behind panels at 240 volts on the electric machines, and behind a gas valve and burner on the gas ones, so neither is opened by an owner.
- Repeatedly clearing the code and running another load is the one response this problem does not tolerate, because the cabinet it is happening in is full of lint.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.