What THERMISTOR Means
WHICH MACHINES THIS APPLIES TO: the text-display machines. The Use and Care Guide for the T711 to T781 range prints "Thermistor" in the T761 and T781 table. The TD70 service manual prints "Thermistor fault" for the TD70.2 and TD70.3 panels. The numeric machines in the same families report the same component as F3.
WHAT ASKO PRINTS FOR THE T761 AND T781: the entry contains one instruction and nothing else - "Call a service technician." The component is named and the meaning is not expanded. That absence is worth stating rather than filling: on those models Asko publishes the component and the action, and no description.
WHAT THE TD70 SERVICE MANUAL PRINTS: two causes, listed as "1. Thermistor circuit open" and "2. Thermistor malfunction", with the service action "Check the thermistor. Replace if necessary." So on that platform the message covers both the wiring going open and the sensor itself misbehaving.
WHAT THE THERMISTOR DOES: it is the temperature sensor in the air path, and the control uses it to decide when the heat goes on and when it goes off. It is the only thing telling the machine how hot the air in the drum is.
WHY THE PROGRAMME STOPS INSTEAD OF CARRYING ON: a dryer that cannot read the air temperature cannot safely keep heating. Some faults let a machine finish in a degraded state; this is not one of them, and the machine stopping is the correct outcome rather than an inconvenience.
WHAT AN OWNER SEES: either the message at the start of a programme, or a machine that has run normally for some time and stops part way through. An intermittent fault that only appears once the machine has warmed up is a recognisable pattern and it usually means a connection opening as it expands rather than a dead sensor.
CLASSIFICATION: fault. There is no published owner check on either platform.
Common Causes of THERMISTOR
- Thermistor circuit open, which the TD70 manual names as its first cause
- Thermistor itself malfunctioning, which the same manual names as its second
- Connector at the sensor loose, corroded or opening as the cabinet warms
- Wiring between the sensor and the control damaged or chafed
- Control unit misreading an otherwise sound sensor
🔧 One Safe Check You Can Try
There is no owner repair for this and neither document offers one, so the useful contribution is an accurate account of the behaviour. Note whether the message appears immediately when a programme starts or part way through, whether it appears on every programme or only on the hotter ones, and whether the loads before it started came out unusually hot or completely cold. Those three answers separate an open connection from a failed sensor before anything is opened, and they are worth writing down rather than trying to remember. If the dryer is going to wait for a visit, switch it off at the wall socket or the breaker and leave it off. Do not remove the back or the lower panel to look at the sensor or its plug. The thermistor on these machines sits in the hot air path at the fan casing, in the same enclosure as the heating element and its overheat cut-outs, all of which are at mains potential whenever the machine is connected to power, and the parts around it stay hot well after a programme ends.
⚠ Why You Shouldn't Go Further Than That
- The thermistor sits in the hot air path next to the heating element and its cut-outs, so the dryer is switched off at the breaker and left to cool before any panel is removed.
- Reaching that enclosure on a stacked or built-in machine means disconnecting the supply and moving the dryer, which is a two-person job.
- A resistance measurement on a thermistor is only valid with the machine isolated and the connector off, so there is no meaningful check to make on a live machine.
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.