Tumble Dryer
F17
The F17 error code on a Siemens tumble dryer signals a fault with the moisture sensor or drying cycle regulation, preventing the drum from completing a timed or auto-dry programme. It’s a moderately serious fault — the dryer may stop mid-cycle — but it’s often something you can resolve yourself.
What does this error mean?
F17 indicates that the Siemens dryer’s moisture sensor strips (located inside the drum) are failing to detect a change in laundry dampness, or the control board isn’t receiving a valid reading from those sensors. In automatic drying modes, the machine relies on these sensors to judge when clothes are dry; if the signal is absent or erratic, the dryer aborts the cycle and throws F17. This can be a sensor fault, a wiring issue, or simply dirty sensor bars causing a false reading.
Est. repair cost
£0 DIY (cleaning fix) · £15–£35 DIY moisture sensor part · £80–£200 professional repair depending on fault
🔍 Likely causes
🛠️ Step-by-step fix
Reset the dryer first: unplug it from the wall, wait 5 minutes, then plug back in and try a fresh cycle. A temporary software glitch can trigger F17 and a hard reset often clears it.
Clean the moisture sensor bars: locate the two small stainless-steel strips on the inside front wall of the drum (usually just below the door opening). Wipe them firmly with a cloth dampened in white vinegar or isopropyl alcohol to remove any fabric softener or limescale film. This single step fixes F17 in a large proportion of cases.
Check and clean the lint filter: remove the filter (typically in the door recess), pull apart the mesh screens, and rinse under warm running water. Allow it to dry fully before reinserting. Do this after every 1–2 loads as a matter of habit.
Clean the condenser unit (condenser/heat-pump models): open the condenser flap at the bottom front of the machine, slide out the condenser, and rinse it gently under a cold tap until the water runs clear. Refit and lock it securely before running a test cycle.
Inspect the wiring at the moisture sensor: if you are comfortable doing so, pull the dryer forward, remove the back or front panel as described in your model’s service diagram, and check that the connector to the moisture sensor is fully seated with no visible corrosion or broken wires. Reconnect any loose plug. Do not attempt this step if you are unsure — proceed to calling a professional instead.
If none of the above steps clear F17, do not attempt to replace the control board yourself — this requires disconnecting mains-voltage components and should be handled by a qualified appliance engineer.
📞 When to call a professional
Call a qualified appliance engineer if F17 persists after cleaning the sensor bars, lint filter, and condenser, or if you suspect a wiring or PCB fault. Tell the engineer you have an F17 fault code, that you’ve already cleaned the moisture sensors and filters, and ask them to check sensor continuity and the wiring harness before quoting for a control board. Siemens-authorised engineers or reputable independent appliance repair companies (check for Which? Trusted Trader or Checkatrade listings) are your best options in the UK.
⚖️ Repair or replace?
A professional repair — typically sensor replacement or a wiring fix — costs around £80–£140 in the UK including parts and labour. If the fault is a control board, expect £130–£200+. As a rule of thumb, if your Siemens dryer is over 8 years old and the repair quote exceeds half the cost of a new equivalent model (budget £350–£600 for a mid-range Siemens condenser or heat-pump dryer), replacement is the more economical long-term choice. For a dryer under 6 years old in otherwise good condition, repair is almost always worth it.