What does the OE error code mean on an LG dishwasher?

LG's wording is that the unit has detected a drain issue, most often resulting from food clogs or an installation issue. It is a drainage code, not a pump-failure code — the machine is reporting that water did not leave when it should have, which has several causes that cost nothing to fix.

How long can an LG dishwasher drain hose be?

LG specifies that it should not exceed 12 feet, and adds that no extension of any type may be added. A hose extended to reach a relocated sink is outside specification even if it is not kinked or blocked.

How high should the drain hose end be?

LG requires the end of the drain hose to be at least 12 in (305 mm) and within 40 in from the base of the appliance, so that water cannot siphon out of the tub. Note that this is measured from the base of the appliance, not from the floor as some other manufacturers specify.

LG's page says 40" (106mm). Which is right?

Those two do not match — 40 inches is roughly 1016 mm. The 12" (305 mm) figure on the same line converts correctly, so the inch values are the internally consistent pair. Use the inch figures and confirm against the installation manual for your specific model.

My LG dishwasher is new and shows OE straight away.

Check the garbage disposal knockout plug. LG states that where the disposal is new, or where a dishwasher is being connected for the first time, the opening for the drain hose may still be plugged, and that the plug must be removed by an installer or plumber. A sealed port produces this code from the first cycle.

LG Dishwasher OE Error Code: Three Numbers, One of Them Wrong

OE is a drainage code. LG’s own definition: the dishwasher “has detected a drain issue, most often resulting from food clogs or an installation issue.”

Note what LG puts in that sentence and what it leaves out. Food clogs or installation. Not a failed pump. The code tells you water did not leave the tub; it does not tell you the machine is broken, and on a large share of these nothing is.

LG publishes three numbers that decide the installation half, and one of them is printed incorrectly on their own page. Both are worth knowing before you measure anything.

The three numbers

Maximum hose length: 12 feet. LG’s wording is unusually firm — “The drain hose should not exceed 12 feet in length. Do not add any type of extension.”

That second sentence is the one that catches people. When a kitchen is reconfigured and the dishwasher ends up further from the drain, the natural fix is a coupler and another length of hose. LG rules that out regardless of the total length.

Minimum height of the hose end: 12 in (305 mm) from the base of the appliance. Below that, drained water runs back down.

Maximum height of the hose end: 40 in from the base of the appliance. Above that, the pump is being asked to lift water further than it was designed to.

Both height limits exist for the same stated reason — “to avoid water being siphoned from the tub.”

About that third number

LG’s page prints the height requirement like this:

The height of the drain hose end must be at least 12“ (305 mm) and within 40“ (106mm) from the base of the appliance to avoid water being siphoned from the tub.

Those two figures do not describe the same distance. Forty inches is roughly 1016 mm. 106 mm is about 4.2 inches — which would be below LG’s own 12-inch minimum on the same line, so the spec would contradict itself.

The 12“ (305 mm) pairing on that line converts correctly, so the inch figures are the internally consistent set. Work in inches: not less than 12, not more than 40, measured from the base of the appliance.

We are not going to tell you what LG meant by the metric figure, because we do not know and guessing at a specification is how people end up installing to a number nobody published. Confirm against the installation manual for your specific model — that is the document that governs your machine, and it is the one to trust if it disagrees with anything here.

We are flagging this rather than quietly quoting the inches because if you are working in millimetres, that page will send you to a height that fails.

Why LG’s rule is not Whirlpool’s rule

If you have read general dishwasher drainage advice, you have probably met the 20-inch figure. Whirlpool specifies a drain loop at least 20 inches from the floor.

These are different rules with different reference points. LG measures from the base of the appliance and sets a window, 12 to 40 inches. Whirlpool measures from the floor and sets a minimum, 20 inches.

They are solving the same problem — stopping wastewater siphoning back into the tub — with different geometry. Applying Whirlpool’s number to an LG, or measuring LG’s window from the floor, gets you a plausible-looking figure that is not the specification for your machine.

Use your manufacturer’s rule, measured from your manufacturer’s datum.

LG’s order, which is worth following

LG lists the steps in this sequence, and it is a sensible one because it runs cheapest-first:

Clean the filter. Food residue is LG’s leading cause and it costs nothing.
Check the drain hose — clogged, kinked, or frozen. That last one is easy to dismiss and genuinely happens where a hose runs through a garage, crawlspace or unheated utility room in winter.
Check the air gap on the sink deck, and the in-sink disposal, for debris.
New dishwasher or garbage disposal — the knockout plug, below.
Force the drain.
Request a repair.

Only the last of those costs money, and it is sixth.

The knockout plug, and who LG says should remove it

For a new installation, this is the most likely single cause:

If the garbage disposal is new or it is the first time a dishwasher has been connected, the opening for the dishwasher’s drain hose may still be plugged. The plug must be removed by either an installer or plumber.

A disposal ships with its dishwasher inlet sealed so it does not leak when installed on its own. If the plug is still in place, the drain hose is clamped onto a closed port and the machine reports OE from its very first cycle. The pump runs normally; nothing moves.

LG describes the removal as done with a hammer and screwdriver — and also says it should be done by an installer or plumber. That is LG’s position and we will leave it there rather than talk you into striking something inside a disposal.

The timing tells you whether this applies. Never drained since installation, or since a new disposal went in: very likely this. Worked fine for two years and started last month: not this.

Force the drain

LG lists this as a step in its own right, before requesting service. It runs the drain pump directly so you can hear whether it is doing anything, which separates a blocked path from a pump that is not running.

The button sequence differs by model and we are not publishing one, because a sequence from a video about a different LG dishwasher either does nothing or puts the machine into a test mode you did not intend. It is in your manual.

When OE is not really about the dishwasher

Everything downstream of the machine belongs to the drainage of your kitchen, not to LG. A blocked disposal, a partially blocked sink waste, or an air gap full of debris all produce this code on a perfectly healthy dishwasher.

The general checks — including how much standing water is supposed to be in the bottom of the tub, which is more than most people expect — are in a dishwasher that is not draining.

And if your machine is showing something other than OE, or a blink pattern rather than a code, start at how to find your dishwasher’s error code.

Where OE usually ends

Food in the filter. LG’s own leading cause, free, and step one for a reason.

A new installation that has never drained. The knockout plug.

A hose that was extended or rerouted during a kitchen job. The 12-foot limit and the no-extension rule, or a hose end outside the 12-to-40-inch window.

Winter, and a hose running somewhere unheated. LG lists frozen explicitly. It thaws.

All clear and OE returns. LG’s own conclusion is that the unit requires repair service. We are not publishing a drain pump part number: they differ across model families and the route to the right one is your model number, from the sticker on the edge of the door, through a parts retailer’s fitment tool. Five of LG’s six steps cost nothing, and between them they account for most of these.