Hoover E4 fault codewhat it means and how to fix it
Too much foam or too much water. Hoover’s entire published remedy is about detergent, which tells you what they think causes it.
Take care
What E4 means
E4, or four flashes of every LED, is published by Hoover as there being too much foam and/or water. Their remedy is one sentence: use the correct amount of detergent, and detergent designed for use in a washing machine. That is unusually direct, and the second half of it is not filler. Washing-up liquid, hand soap and dishwasher products in a washing machine drum produce foam that a machine designed around low-foam detergent cannot cope with, and it is a genuine cause rather than a hypothetical one.
What makes foam more than a nuisance is what it does to the machine’s senses. The water level is measured by pressure in an air tube connected to the tub, and foam is neither air nor water: it compresses wrongly, so the machine can no longer tell how much water it has.
Foam also climbs into the pressure tube itself and into the pump, so a machine full of it fails to spin, fails to drain properly and can end up reporting drainage or level faults on top of this one. Note that Hoover’s wording is foam and/or water, which puts genuine overfilling in the same row — a fill valve that passes water when it should be closed reaches the same result with no foam involved at all.
What causes it
| Cause | What is actually happening | How likely |
|---|---|---|
| Too much detergent for the load | Hoover’s own explanation, and the usual one. Dosing for a full drum on a half load, or dosing for hard water in a soft water area, gives foam the machine cannot clear. | Common |
| The wrong product entirely | Washing-up liquid, hand soap or a dishwasher product in the drawer. Hoover specify detergent designed for use in a washing machine because this genuinely happens. | Occasional |
| Detergent residue from previous washes | Powder builds up in the drum and the drawer on cool cycles and releases all at once on a warmer one, so the foam appears on a wash that was dosed correctly. | Occasional |
| A load that foams by itself | New towels, microfibre cloths and anything previously washed with a heavy dose carry their own detergent into the drum before you add any. | Occasional |
| Fill valve passing water | The and/or water half of Hoover’s wording. A valve that does not close fully overfills the tub with no foam at all, and standing water after the machine has been off overnight is the tell. | Rare |
What to try yourself
Cancel the programme and let the machine stand. Foam collapses on its own given time — Hoover put no figure on it — and everything else is easier once it has.
Run a rinse and spin with no detergent at all. Repeat it if the water in the glass is still cloudy. This is the quickest way to get the foam out of the machine rather than out of the drum.
Check what went in the drawer. If it was anything other than machine washing detergent — washing-up liquid, hand soap, a dishwasher tablet — that is your answer, and it will take two or three rinses to clear.
Halve your normal dose for the next few washes. If you are in a soft water area, the dose on the back of the box is written for hard water and is too much for you every single time.
Clear the pump filter once the foam has gone, because it will have collected some. Then run Hoover’s own drum clean to shift the residue that has built up: the Auto-Hygiene cycle on One Touch models, or the monthly service wash the manual recommends, with an empty drum and a proprietary washing machine cleaner or powder detergent as they specify, and the door left open afterwards to dry. Hoover suggest it every 50 washes.
If this happens again on a correctly dosed load, look in the drum after the machine has stood off overnight. Water sitting in an empty machine means the fill valve is passing and that is a repair rather than a habit.
Get a qualified appliance engineer to look at your Hoover E4
We do not pass enquiries to a repair firm, so there is no form here. When you book a qualified appliance engineer, tell them the make, the model and the exact code or message on the display, and ask whether they carry parts for this make — that is what turns one visit into a repair rather than a quote.
What it costs to fix
Typical repair cost
£0–£160
Time on site
1 hour
Nothing in almost every case — rinses and a change of dosing. A fill valve fitted is £95 to £160 if genuine overfilling turns out to be the cause rather than foam.
Typical UK prices including parts and labour, updated September 2026. Your quote may differ.
Own this appliance and had this code? . Nothing is published until a person has read it.
Related Hoover fault codes
- E3Get it checkedThe machine is not draining. Hoover’s remedy runs from the filter outwards to your own plumbing, and one step tells you how to empty it into the sink.Related: same brand
- E2Get it checkedThe machine cannot load water. Hoover send you to a filter most owners have never heard of, inside the fill hose connection at the back of the machine.Related: same brand
- E7Get it checkedA door problem. If the door is locked shut, Hoover want you to unplug and wait two to three minutes before trying it again, and the wait is the point.Related: same brand
Own a Hoover washing machine? Save it and its codes come first next time.
Related guides
Common questions about Hoover E4
How much detergent should I actually use?
Less than the box says, in most of the UK. Dosing instructions are written for a full drum in a hard water area, so a half load in a soft water area needs perhaps half of it. If your clothes come out feeling slightly stiff, or the drum smells of detergent when it is empty, you are using too much.
Can foam damage the machine?
It is not usually destructive, but it does more than look dramatic. Foam gets into the pressure tube the machine uses to measure water level, so the machine stops knowing how full it is, and it gets into the pump, so spins fail. Clear it out properly rather than pushing through, or you will collect a drain code on top of this one.
Why does E4 mention water as well as foam?
Because Hoover’s wording is too much foam and/or water, which covers genuine overfilling. If there is no foam in the glass and the machine still reports this, suspect a fill valve that is not closing fully. Standing water in a drum after the machine has been off overnight confirms it.
I used a liquid tab, not powder. Can that still foam?
Yes. Tabs and capsules are dosed for a full load and cannot be split, so a small wash gets a full dose by design. They are also the easiest way to over-dose without feeling like you have, because there is no scoop to look at.
Technical review
Not reviewed by an engineer
No engineer has read this page. Severity follows what the manufacturer publishes, and we would rather tell you that than let a byline imply a sign-off.
Sources and how we verified this
We establish the facts from the sources below and then write the explanation ourselves. We do not copy manufacturer wording and we do not host their manuals.
- Manufacturer technical and service documentation
This page has not been reviewed by an engineer, and we would rather tell you that than imply otherwise. The severity rating follows what the manufacturer publishes: where they say isolate the appliance and call someone, so do we.