Dishwasher
F12
The F12 error code on a Hoover dishwasher indicates a water fill or inlet problem — the machine isn’t detecting enough water entering the drum within the expected time. It’s a moderately common fault that’s often fixable at home, but can require a professional if the inlet valve or control board has failed.
What does this error mean?
F12 signals that the dishwasher’s control board has timed out waiting for the drum to fill with water. The machine monitors how long it takes to reach the correct water level via a pressure sensor or float switch — if it takes too long or water doesn’t arrive at all, it throws F12 and stops the cycle. This is a protective measure to prevent the pump and heating element from running dry.
Est. repair cost
£80–£150 professional repair; £15–£35 DIY inlet valve part if self-replacing
🔍 Likely causes
🛠️ Step-by-step fix
Turn the dishwasher off at the mains and turn off the water supply tap (usually under the sink). Wait 10–15 minutes, then power back on and run a short cycle — a simple reset clears temporary faults.
Check the water supply tap under the sink is fully open. It sounds obvious, but a partially closed tap is a surprisingly common cause of F12.
Inspect the inlet hose at the back of the machine. Straighten any kinks, ensure it isn’t pinched behind the appliance, and confirm it’s securely connected at both ends.
Unscrew the inlet hose from the back of the dishwasher and check the small mesh filter screen at the connection point. Rinse it under the tap and use a soft brush to clear any limescale or debris.
Run a hot tap nearest to the dishwasher for 30 seconds before starting a cycle — this confirms your household water pressure is adequate and purges any air from the line.
If all of the above checks out and F12 persists, the inlet solenoid valve is the most likely culprit. Replacement valves for Hoover dishwashers cost £15–£35 online. This involves pulling the machine out, disconnecting the hose, and removing a single panel — a confident DIYer can do this, but if you’re unsure, call an engineer.
📞 When to call a professional
If the inlet hose, filter, and water supply are all fine but the error persists, stop DIY and call an appliance engineer — the inlet valve or pressure switch likely needs replacing, or worse, the control board has failed. When calling, tell the engineer you have a Hoover dishwasher showing error code F12, that the water supply and inlet hose have already been checked, and ask them to quote for an inlet valve replacement as a starting point.
⚖️ Repair or replace?
A professional repair for F12 — typically an inlet valve or pressure switch replacement — costs £80–£150 including labour in the UK. If your Hoover dishwasher is under 5 years old, repair is almost always worth it. For machines over 8–10 years old, weigh the repair cost against a new mid-range dishwasher (£300–£500), especially if other components are ageing — replacement often makes more financial sense.