What E21 actually means
The machine can't tell how much water is inside, so it stops rather than risk filling or heating blind.
On Hoover washing machines E21 means the control board is getting no signal at all from the APS pressure sensor that measures the water level in the drum. Without that reading the machine has no way of knowing when to stop filling or whether it is safe to heat, so it halts the cycle — usually early on, at the fill stage. On models without a display you'll see this as 11 flashes of the indicator light between pauses.
What usually causes it
- Faulty APS pressure sensor (the water level sensor)
- Damaged or disconnected wiring between the sensor and the control board
- Blocked or split pressure hose feeding the sensor
- Failed "Cuore" main control board — less common, but it does happen
What you can safely check yourself
Work through these in order. Anything beyond this — panels off, testing parts, anything to do with the wiring — is an engineer's job, and not one to attempt with the machine plugged in.
- Turn the machine off at the wall for a minute, then switch back on and try a short cycle — occasionally the code is a one-off and clears
- Check the machine isn't sitting with standing water in the drum from an aborted cycle; if it is, run a drain or spin programme
- Clean the pump filter at the front, as a badly clogged one can leave the machine sitting full and confuse the picture
When to call someone
This one usually needs an engineer once you have tried the checks above. We cover Nottinghamshire, Derbyshire and Leicestershire, and it's £66 including VAT for an engineer to come out and diagnose it — £84 in total if it's repaired on the visit with no parts needed. Any parts needed are quoted on site before we fit them — you decide. Every repair carries a 90-day workmanship guarantee.
Outside our area? The explanation above still stands — take it to a local engineer and tell them the code. Knowing it saves them time and you money.
Other Hoover washing machine codes
- Hoover E01 — The machine can't confirm the door is locked shut, so it ref…
- Hoover E02 — The machine hasn't taken in enough water in the time it allo…
- Hoover E03 — The machine hasn't managed to empty the water out within the…
- Hoover E04 — The machine has decided it's being overfilled with water and…
- Hoover E05 — The machine can't get a sensible reading from the sensor tha…
- Hoover E07 — The machine thinks the door lock is stuck in the locked posi…
- Hoover E08 — The machine can't tell how fast the drum motor is turning, s…
- Hoover E11 — The machine can't see a working drying heater circuit, so it…