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Ariston F08 on a washer dryer

Heating fault — the heater relay or the element circuit has failed.

The same code appears on Hotpoint, Indesit and Whirlpool machines — they share the same control platform.

Verdict

Needs an engineer

Mains electrical, gas or sealed-system work

Urgency
Fix soon

About 50 min to work through

Typical cost

£95–£230

What F08 actually means

The board tried to heat the wash water and the feedback did not match what it expected — either the element is open circuit, the relay driving it has stuck, or the temperature sensor is lying to it. On some models the machine stops mid-cycle; on others it completes but washes cold. Because it involves a mains-voltage heating circuit, this is one to hand over.

Before you start

  • Electrical safety: The heating circuit carries high current at mains voltage and a stuck relay can leave the element live unexpectedly. Do not test or replace it yourself unless you are qualified to work on mains appliances.

What causes it, most likely first

  1. Failed heating element

    Most likely

    The element under the drum goes open circuit, usually after limescale has insulated it and driven it to overheat. Common in hard-water areas and on machines run mostly on low-temperature cycles.

    Heating element£15–£40 for the partEngineer

  2. Welded or failed heater relay on the control board

    Common

    The relay that switches the element can weld shut or fail open. A welded relay is the more serious case because the element can heat when it should not.

    Main control board (PCB)£70–£220 for the partEngineer

  3. Failed NTC temperature sensor

    Common

    If the sensor stops reporting a rising temperature, the board concludes the heater has failed even when it is working perfectly.

    NTC temperature sensor£8–£22 for the partEngineer

  4. Corroded element connections or chafed wiring

    Occasional

    The spade terminals on the element corrode in the damp environment behind the drum, adding resistance until the circuit reads as broken.

    Wiring loom / connector£10–£45 for the partEngineer

How to fix it, step by step

  1. Confirm what the machine is actually doing

    Run a 60°C cycle and feel the door glass twenty minutes in. Warm glass means the element is working and the fault is more likely to be the sensor. Cold glass throughout points at the element or the relay.

    30 min

  2. Power-cycle to clear a latched fault

    Switch off at the wall for five minutes and restore power. A single glitch will clear; a genuine heating circuit fault will come straight back.

    10 min

  3. Try a cold wash to keep using the machine safely

    If you need a wash before the engineer arrives, a cold or 20°C programme avoids the heating circuit entirely on most models. Stop using it altogether if you smell burning at any point.

    5 min

  4. Book an engineer and quote the code

    Say it is an F08. It tells them to bring an element and to test the relay and NTC, which often turns two visits into one. Ask for the all-in price before they start.

    5 min

Need an engineer for this F08?

We list 4 washer dryer repair businesses across the UK. Diagnostic callouts typically start around £55, and many will put that towards the repair if you go ahead.

Find washer dryer engineers near you

Parts you might need

Typical UK prices for the part alone, before fitting. Worth knowing before you accept a quote — the part is often a small share of what a repair is priced at.

  • NTC temperature sensor

    A small thermistor that tells the control board how hot the water is. When it fails the board usually assumes the worst and stops heating.

    £8–£22

  • Wiring loom / connector

    Chafed wires and corroded connectors mimic dead components. An engineer will always check continuity before condemning a part.

    £10–£45

  • Heating element

    The element sitting under the drum that heats the wash water to the selected temperature.

    £15–£40

  • Main control board (PCB)

    The appliance brain. Genuine boards are expensive and often need configuring to the model, so this is rarely a DIY part.

    £70–£220

Worth repairing, or replace it?

At the top of this range the repair costs a significant share of a graded replacement, which typically starts around £280. Worth getting the quote first, then deciding — on a machine under about five years old a repair usually still wins.

Work out if it's worth fixingCompare graded washer dryers

Related problems

Other Ariston washer dryers codes

All Ariston washer dryers fault codes