E18Bosch · Dishwasher · Dishwasher

Bosch Dishwasher error code E18

Water flow too low to fill the tub

Needs attention soon

Quick answer

On Bosch Dishwasher (2000s onward), E18 is a fault. It means water flow too low to fill the tub. A first thing to check: Supply tap closed partway or the house valve not fully open.

Applies to: Bosch Dishwasher; Bosch dishwasher codes · Dishwasher · 2000s onward
Type of code: Fault; Urgency: Needs attention soon
First safe check: Open the tap the hose is connected to all the way, then confirm it stays open for the length of the cycle.

Checked 2026-09-26

What E18 means on this model

The machine did not get the water volume it needed within the fill time, which points at the supply rather than at the machine. Bosch specifies about ten litres a minute through the tap, so a partly closed supply valve or a hose kinked behind the cabinet explains most of these.

Symptoms you will notice

Machine stays full of nothing and the door will not unlock
Drum is completely empty when you open it
Cycle sits at the first fill step for several minutes
Clothes come out dry because no water ever entered

Common causes

The code tells you what the control detected, not which part failed. These are the causes we see most often, roughly in order of likelihood:

Supply tap closed partway or the house valve not fully open
Inlet hose kinked, crushed behind the machine, or frozen
Inlet hose connected to a hot tap when the cycle wants cold
Debris in the mesh screen at the valve end of the inlet hose
Failed inlet valve or valve solenoid
Weak household water pressure

What you can safely check

These are homeowner-level checks. None of them need you to open a live electrical compartment or work on gas.

Open the tap the hose is connected to all the way, then confirm it stays open for the length of the cycle.
Trace the inlet hose behind the machine. Pull it forward and look for a crush mark, a tight bend, or a kink at the fitting.
Hold a glass under the tap for ten seconds. Weak flow there is the whole answer.
Close the tap, unscrew the inlet hose at the machine, and look at the small mesh screen in the end of the hose.
Compare the hose markings to the tap markings. Blue to blue and red to red, on a machine with both hoses.

Do not do these

×Do not use a hose that is too long or too small a diameter. Restricted flow makes the level sensor report a fault that is not really there.
×Do not leave a hose routed over a sharp appliance edge, which flattens it without anyone noticing.

When to call a technician

Book a technician, do not keep resetting it

This fault will not clear on its own. Every power cycle gives the control one more failed attempt, and repeated attempts are what turn a cheap part replacement into a seized or contaminated system.

If the appliance has stopped mid-cycle, is making a noise you have not heard before, or smells burnt, stop reading here and call. Those are symptoms of something the fault code does not describe well enough.

Replacing a hose and cleaning a screen is straightforward. A valve replacement means pulling the machine out and working in a wet cabinet, so it is a technician job for most people.

What it costs to fix

Parts

Inlet hose under $20. Inlet valve or solenoid $30 to $90. Pressure switch on older platforms $25 to $60.

Labor

Thirty minutes to an hour for a hose or screen. Budget an hour to an hour and a half if the valve has to be replaced behind the machine.

DIY or technician