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F18

Error code

high severity Siemens

F18 Error: # Siemens Dishwasher F18 Error Code Your Siemens dishwasher

# Siemens Dishwasher F18 Error Code Your Siemens dishwasher has stopped mid-cycle and is displaying the F18 error code on its display panel. This indicates that your machine has detected a water heating fault, meaning the water inside hasn't reached the temperature needed to wash your dishes properly. Whilst this might sound concerning, the good news is that many F18 faults can be resolved without calling out an engineer. The most common culprits behind this error are relatively straightforward to check yourself. The heating element, which warms the water, is often the main suspect and may have simply failed or accumulated limescale over time. The temperature sensor, which detects whether the water has heated sufficiently, could also be faulty or loose. Additionally, the inlet hose delivering water to your machine might be kinked or blocked, or there could be an issue with the thermostat that controls the heating process. Before you panic or book an expensive repair visit, this guide will walk you through the likely causes and what you can safely inspect yourself to potentially resolve the problem.

Diagnostic Steps

  1. 1

    Step 1

    Check the heating element is not scaled up — descale if necessary

  2. 2

    Step 2

    Test the NTC thermistor for correct resistance

  3. 3

    Step 3

    Inspect wiring connections to the heater

  4. 4

    Step 4

    If element is faulty, replacement is required

⚠️ Always disconnect your appliance from mains power before starting any repair. If in doubt, consult a qualified engineer.

Frequently Asked Questions

What does the F18 error mean on a Siemens dishwasher?↓
# Siemens Dishwasher F18 Error Code Your Siemens dishwasher has stopped mid-cycle and is displaying the F18 error code on its display panel. This indicates that your machine has detected a water heating fault, meaning the water inside hasn't reached the temperature needed to wash your dishes properly. Whilst this might sound concerning, the good news is that many F18 faults can be resolved without calling out an engineer. The most common culprits behind this error are relatively straightforward to check yourself. The heating element, which warms the water, is often the main suspect and may have simply failed or accumulated limescale over time. The temperature sensor, which detects whether the water has heated sufficiently, could also be faulty or loose. Additionally, the inlet hose delivering water to your machine might be kinked or blocked, or there could be an issue with the thermostat that controls the heating process. Before you panic or book an expensive repair visit, this guide will walk you through the likely causes and what you can safely inspect yourself to potentially resolve the problem.
Can I fix the F18 error myself?↓
Many F18 faults can be resolved by a competent DIYer. Always disconnect from mains power first. If unsure, consult a qualified engineer.

Quick Summary

Code
F18
Brand
Siemens
Parts to check
0