If water does not appear to be coming into a Bosch WAT28400UC, Bosch's troubleshooting lists the causes and remedies: Start/Pause not selected (select it), the water taps are not turned on (turn them on), the supply hose is kinked or pinched (eliminate the cause), the water supply hose strainers are clogged (clean the water inlet strainers) and the water pressure is too low (eliminate the cause). The manual's error messages add: a cold water tap not turned on, a supply hose for cold water kinked, a strainer clogged or cold water pressure too low, and E:93 for hot water not available, shown at the end of the first cycle without hot water. Water that cannot be seen in the drum is normal.
Differential
Likely causes of “Bosch 300 Series WAT28400 front-load washer will not fill with water or fills too slowly”, and how to tell them apart
- 1
Taps off or Start/Pause not touched
What separates it There is no fill because the taps are off or Start or Pause was not touched
How to confirm Turn on the taps and select Start or Pause
- 2
Kinked or pinched hoses
What separates it There is a trickle or nothing because the hoses are kinked or pinched
How to confirm Eliminate the cause, and replace a damaged hose
- 3
Clogged strainers
What separates it There is a slow or stopped fill because the strainers are clogged
How to confirm Clean the strainers at the tap end and the washer end of each hose
- 4
Low water pressure
What separates it There is a slow fill because of low water pressure
How to confirm Check the other taps, and eliminate the cause
Before you touch a setting
Record this first — changing settings destroys the evidence
- Which message or symbol showed, for example E:93
- Whether hot and cold taps are on
- Whether the hoses are kinked or pinched
Try in this order
0 of 5 completedCheck the taps
ReversibleCheck the taps, and make sure that both are on and Start or Pause was touched.
Check the hoses
ReversibleCheck the hoses, which must not be kinked or pinched, and replace a damaged hose.
De-pressurize
ReversibleDe pressurize, by turning the tap off, selecting a wash cycle, touching Start or Pause, waiting 30 seconds and turning the selector to Off.
Clean the strainers
ReversibleAt the tap end and at the washer end using narrow pliers to pull the strainer from the inlet port; rinse under running water.
Reconnect and test
ReversibleReconnect and test, by turning on the tap and starting a warm water cycle to check the flow.
Model-specific
What is true of this model and not of its siblings
- Strainers at both ends
- The washer has strainers at the tap end of each supply hose and at the inlet ports on the back of the washer. If the water supply slows or stops completely, a strainer may be blocked; cleaning every 6 months reduces valve blockage in hard water areas. Rinse each strainer under running water and check that no debris is visible, then reconnect with the rubber washers seated at both ends.
- E:93 hot water
- E:93 displays at the end of the first cycle without hot water and is not displayed in later cycles if hot water is still unavailable; it is reset after a second cycle with hot water. Bosch's fix is to turn on the hot water tap, eliminate a kinked or pinched hot hose, check hot water pressure and clean the hot strainer, and to connect both supply hoses (hot and cold) for hot water appliances.
- Parts for this problem on the WAT28400 (RepairClinic, 2026-09-20)
- water inlet valve, part number 00635399, at $146.39; pressure sensor, part number 10009438, at $43.31; outlet hose, part number 11006030, at $53.33.
- Other models this page answers
- These steps also fit the 300 Series WGA12400UC washer, 800 Series WAW285H2UC washer, 800 Series WGB24600UC washer.
Stop boundary
When this stops being a self-service repair
- !If the fill fault persists after cleaning the strainers and confirming pressure, call Bosch customer service
- !If E:93 continues after both hoses are connected and hot water is available, call service
Evidence ledger
Sources behind this answer
Bosch's own US owner-support pages for washer error codes and self-help.
Parts and list prices as shown on RepairClinic's parts search for this model number on 2026-09-20.
Exact questions
Common questions
Why is no water coming into my Bosch washer?+
Taps off, Start/Pause not touched, kinked hoses, clogged strainers or low pressure.
How often should I clean the strainers?+
Bosch recommends every 6 months, especially in hard water areas.
Which hose is hot?+
Red is hot and blue is cold.
How do I check the flow?+
Start a warm water wash cycle after reconnecting.