Siemens E15 on a dishwasher
Anti-flood float has tripped — water is sitting in the base of the dishwasher.
The same code appears on Bosch and Neff machines — they share the same control platform.
DIY-able with care
Involves dismantling or a part swap — confident DIYers only
About 57 min to work through
Free to £200
DIY: Up to £60 in parts
What E15 actually means
Bosch dishwashers have a polystyrene float in the base tray. Water collecting under the tub lifts it, which trips a microswitch, locks the machine out and usually leaves the drain pump humming continuously. The lockout is deliberate: the machine is trying not to flood your kitchen. It is also, happily, one of the more fixable dishwasher faults.
Before you start
Electrical safety: You will be tilting an appliance with water in its base while it is plugged in unless you isolate it first. Unplug at the wall before you start.
Water: Turn off the supply tap as well, in case the leak is on the fill side.
What causes it, most likely first
Water in the base tray from a minor internal leak
Most likelyVery often a small amount of water has found its way into the base over months — from a weeping seal, an overfilled salt reservoir, or a one-off overflow — and has finally reached the float.
How to check: Tilt the machine back and see whether water runs out of the base. If it does, drying it out may clear the fault entirely.
Salt spilled into the base or an overfilled salt reservoir
CommonSpilling salt when refilling, or overfilling until brine escapes, corrodes and leaks into the base. A classic cause a few weeks after someone first topped the salt up.
Leaking door seal or detergent dispenser
CommonWater escaping past the door seal runs down the inside of the door and into the base rather than onto the floor, so the leak is invisible until the float trips.
Split sump, spray-arm feed or hose connection
OccasionalInternal hoses and their clips harden with heat cycling. Finding the split usually means removing the machine and taking the side panel off.
Failed heat exchanger or tub seam
RareA perforated heat exchanger leaks continuously and is generally the point at which replacing the machine beats repairing it.
How to fix it, step by step
Isolate the machine and turn off the water
Unplug at the wall and close the supply tap under the sink. If the pump is droning, unplugging is the only way to stop it.
2 minBail out any standing water in the tub
Scoop water from the sump with a cup and finish with a sponge, then lift out the filter assembly at the bottom and clean it thoroughly under the tap. A blocked filter is often part of the story.
10 minCup, SpongeTilt the machine to drain the base tray
With a helper, ease the machine out and tilt it backwards about 45 degrees over towels, holding it for a minute or two. Water in the base will run out at the back. This alone clears the fault on many machines.
15 minTowelsLeave it to dry, then restore power
Stand the machine upright and leave it several hours — overnight is better — for the base to dry fully. Then plug in and run a short empty cycle, watching for the fault to return.
10 minIf E15 comes straight back, find the leak
A fault that returns within one cycle means water is still actively getting into the base. Check the salt cap is tight and the seal intact, and look hard at the door seal. Beyond that it needs an engineer with the side panel off.
20 min
Need an engineer for this E15?
We list 75 dishwasher repair businesses across the UK, 28 of which are Siemens-authorised. Diagnostic callouts typically start around £55, and many will put that towards the repair if you go ahead.
- 0800 037 4915London
- 01344 669700BracknellSame day
- 01634 557996Chatham
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 £190. Worth getting the quote first, then deciding — on a machine under about five years old a repair usually still wins.