What causes Miele Washer F20?

A failed heater element, including one whose built-in overheating protection has tripped (Miele technical documentation: a tripped protector means the element must be replaced as an assembly). An open or short circuit, or poor insulation, in the heater element wiring and connections (Miele technical documentation). A faulty heating relay or power electronics that don't switch the element on (repair-level check behind the heater circuit test). A one-off glitch that clears after a 2-minute power reset (Miele support). The NTC water temperature sensor sits in the heater element seal; Miele uses separate codes (F1 short, F2 open) for a failed sensor, so a technician checks it against its resistance table while testing the heating.

How do I fix Miele Washer F20?

If the countdown has just paused mid-wash, give it time. Miele explains that Thermostop pauses the time-left display until the water reaches the set temperature, then the program carries on. If F20 or Heating fault is shown, unplug the machine or switch off the breaker (or fuse). Wait at least 2 minutes, then reconnect the power and switch the machine on. Restart the program. Miele says that if the fault persists, contact Miele Service or book a repair online. Until it's repaired, you can usually still wash on cold programs, but warm and hot washes won't heat properly. Note the program and temperature you used when F20 appeared, since it helps the technician.

When should I call a pro for Miele Washer F20?

F20 comes back after the 2-minute reset: Miele says to contact Miele Service. A technician tests the heater element circuit for an open or short circuit and correct insulation, as Miele's technical documentation directs, and replaces the heater element (with a new seal) if it has failed or its overheating protector has tripped. The NTC temperature sensor in the element seal is checked against Miele's resistance table (about 12.0 kOhm at 25 C, 4.52 kOhm at 50 C). If the element and wiring test good, the heating relay and electronics are checked next. The machine is under warranty or extended cover: use Miele Service first.

Code: F20🧺 Miele Washer

Miele Washer F20: Heating Fault (Water Not Reaching Temperature) Meaning and Fixes

Q: What does Miele Washer F20 mean?

F20 (or "Heating fault") on a Miele washing machine means the water didn't reach the selected temperature in the time allowed. Miele says to unplug the machine or switch off the breaker, wait at least 2 minutes, switch it back on and restart the program. If F20 comes back, the heating circuit has a fault, usually the heater element or its wiring, and Miele says to contact Miele Service. Miele's support pages in the US, UK and Australia say Fault F20 or Heating fault is shown when there is a fault with the heating. They also explain the Thermostop function behind it: Thermostop makes sure the set program temperature is reached. If the water hasn't reached temperature within the specified time, Thermostop starts and the time-left display pauses; once the temperature is reached, the program resumes. A paused countdown on its own is normal, but when heating still fails, F20 is stored. Miele's technical documentation for its washers (the Touchtronic W1113 family and the PW 5065/6055/6065 range) lists F20 as a heating fault with the cause "the selected temperature has not been reached before the Thermostop time has elapsed; the heating is defective," and symptoms of poor wash results, suds that aren't warmed and long program times. The service check is the heater element circuit for an open or short circuit and correct insulation.

Reviewed 2026-10-26 · Based on 5 manufacturer & service sources

What the code means

Miele's support pages in the US, UK and Australia say Fault F20 or Heating fault is shown when there is a fault with the heating. They also explain the Thermostop function behind it: Thermostop makes sure the set program temperature is reached. If the water hasn't reached temperature within the specified time, Thermostop starts and the time-left display pauses; once the temperature is reached, the program resumes. A paused countdown on its own is normal, but when heating still fails, F20 is stored. Miele's technical documentation for its washers (the Touchtronic W1113 family and the PW 5065/6055/6065 range) lists F20 as a heating fault with the cause "the selected temperature has not been reached before the Thermostop time has elapsed; the heating is defective," and symptoms of poor wash results, suds that aren't warmed and long program times. The service check is the heater element circuit for an open or short circuit and correct insulation.

Likely causes

A failed heater element, including one whose built-in overheating protection has tripped (Miele technical documentation: a tripped protector means the element must be replaced as an assembly)
An open or short circuit, or poor insulation, in the heater element wiring and connections (Miele technical documentation)
A faulty heating relay or power electronics that don't switch the element on (repair-level check behind the heater circuit test)
A one-off glitch that clears after a 2-minute power reset (Miele support)
The NTC water temperature sensor sits in the heater element seal; Miele uses separate codes (F1 short, F2 open) for a failed sensor, so a technician checks it against its resistance table while testing the heating

Safe DIY checks

⚠ Before you start

Miele's technical information warns that the heater circuit still carries mains voltage (240 V) even with the machine switched off, so it must be unplugged or the breaker switched off before anyone touches it. Heater element and sensor checks mean removing the front panel and draining water, which is a job for a trained technician. Don't run the machine with exposed or damaged wiring.

If the countdown has just paused mid-wash, give it time. Miele explains that Thermostop pauses the time-left display until the water reaches the set temperature, then the program carries on.
If F20 or Heating fault is shown, unplug the machine or switch off the breaker (or fuse).
Wait at least 2 minutes, then reconnect the power and switch the machine on.
Restart the program. Miele says that if the fault persists, contact Miele Service or book a repair online.
Until it's repaired, you can usually still wash on cold programs, but warm and hot washes won't heat properly. Note the program and temperature you used when F20 appeared, since it helps the technician.

🛠 When to call a pro

F20 comes back after the 2-minute reset: Miele says to contact Miele Service.
A technician tests the heater element circuit for an open or short circuit and correct insulation, as Miele's technical documentation directs, and replaces the heater element (with a new seal) if it has failed or its overheating protector has tripped.
The NTC temperature sensor in the element seal is checked against Miele's resistance table (about 12.0 kOhm at 25 C, 4.52 kOhm at 50 C).
If the element and wiring test good, the heating relay and electronics are checked next.
The machine is under warranty or extended cover: use Miele Service first.

Parts that commonly fix it

Always match the part number to your exact model.

⚙

Washer heating element (exact Miele part for your model)

Only after a technician confirms the element has failed. Miele says a new seal and retaining washers must go in with a new element. Order by model and serial number.

Search eBay →

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Digital multimeter

For checking the heater element for an open circuit and the NTC sensor's resistance with the power disconnected.