What to check yourself
Step 1. Work out what went into the dispenser
The answer is nearly always washing up liquid, the kind meant for a sink. It is the single most common cause and it is usually somebody in the house helping out. Dishwasher detergent is deliberately low foaming; hand dish soap is the opposite, and a squirt is enough to fill the machine with suds.
Step 2. Rinse the foam out before running anything else
Run a rinse only cycle with no detergent at all, twice if there is visible foam left. Some technicians add a splash of white vinegar or a spoon of salt to the tub to knock the bubbles down faster, which is safe and works.
Step 3. Check the rinse aid setting
This is the cause people never suspect. A rinse aid dispenser turned up to its maximum, or a lid not clicked shut so it empties in one go, produces persistent foam with entirely correct detergent. Look at the dial inside the door and turn it down a notch.
Step 4. Check the machine is level
LG names this alongside detergent, and the connection is not obvious: a machine tilted forward lets water and foam sit against the door seal instead of draining back to the sump. A spirit level across the bottom rack and a turn of the front feet settles it.
Step 5. Cut the detergent dose down
For a normal load in average water, most people use roughly twice what is needed. One tablet, or a filled main compartment, is plenty. Adding extra powder on top of a pod is what starts this in the first place.
When to call a technician
Rarely, and only if the code keeps coming back with correct detergent, a sensible rinse aid setting and a level machine. At that point the suspicion moves to the sensor or a water softener dosing wrongly, and that needs testing rather than another rinse cycle.
What the repair costs
| Repair | Part only | Fitted by a technician |
|---|---|---|
| Rinse cycles and a change of detergent | - | Free |
| Levelling the machine | - | Free |
| Diagnosis, if it persists with correct detergent | - | $75 to $130 |
A new machine of the same class runs $500 to $1,500. Once a quote passes about a third of that on an older appliance, the repair stops making sense.
Codes people confuse this with
Questions people ask
- I only used a tiny bit of washing up liquid. Surely that is not enough?
- It is. Hand dish soap is formulated to foam, and a dishwasher sprays water at it under pressure for an hour. A teaspoon can fill the tub. There is no dose that is safe here, which is why the answer is a rinse and a fresh start rather than less of it.
- How do I get rid of foam quickly?
- Rinse cycles with no detergent. If it is stubborn, a cup of white vinegar or a spoonful of ordinary salt sprinkled onto the foam collapses it faster. Both are harmless to the machine.
- My Samsung dishwasher showed bE and it was a button. Which is right?
- Both. The letters mean different things to different manufacturers: foam on an LG, a stuck button on a Samsung. Check the badge on the door before following any advice you find.
Which machines this applies to
Applies to
LG dishwashers across the LDF, LDT, LDP and LSDF ranges. Worth knowing before you search: on a Samsung dishwasher these same two letters mean a stuck button, not foam.
Last checked
2026-08-10