The short answer
When a Ostba washer will not drain, the usual cause is the pump filter or lint trap loaded, and on this platform it is far more often the route the water takes than the pump that moves it. This is a compact automatic machine with programmes of its own, hose-fed and hose-drained rather than plumbed in, and that is what sets the order below. These are fitted under a counter in an office or a small kitchen, which means a cutout, a fixed position and very little airflow at the back.
What you observe
- Water standing in the tub at the end of the cycle — The complaint in its plainest form.
- It drains slowly rather than not at all — Slow and stopped have different causes; note which you have.
- The pump hums with no water moving — Something is stopping the flow rather than the pump failing.
- The tub empties while it should still be washing — The opposite fault, and it comes from the same hose.
- NEAR MISS — water is on the floor rather than in the tub — That is a leak, and the leak page for this appliance is the right one.
Causes, most likely first on this platform
- The pump filter or lint trap loaded — Ranked immediately after the routing because it is the most common physical blockage and the easiest to clear: hair, lint, a coin or a hair grip collects at the filter and the flow drops to nothing over a few weeks. Anything that depends on air behind the cabinet is therefore compromised before the appliance has done anything wrong.
- The drain hose higher than the machine can lift water — First on a portable, and it is a design constraint rather than a defect: these machines drain by gravity or with a very small pump, and a hose hooked over a tall sink or run up a wall simply will not empty.
- A kinked or crushed hose — A machine pushed back against a wall traps its own hose.
- A blocked standpipe or sink downstream — The machine may be innocent.
Check in this order, and why
- First: open the filter cover and clear the trap — Second because it is the most common physical blockage and it is designed to be opened by the owner. On a unit fixed into a cutout, start with what the cutout is doing to the air behind it.
- Second: lay the drain hose low and run the drain step again — It tests the top-ranked cause without tools, and on this platform it is usually the whole answer.
- Third: pull the machine out and follow the hose along its whole length — A crush point is never at the end you can see.
What an owner can safely check
- Open the filter cover and clear the trap — Put a shallow tray and a towel down first — there is more water behind it than people expect.
Tools: shallow tray, towelsAbout 20 min
- Lay the drain hose low and run the drain step again — On this platform the routing decides whether the water can leave at all, and this is usually the whole answer.
About 15 min
- Pull the machine out and follow the hose along its whole length — A crush point is never at the end you can see.
Tools: flashlightAbout 15 min
- STOP HERE before removing the pump — Bail the tub out first if you must move the machine, and hand it over rather than opening the cabinet.
Before you open anything
Safety
Unplug the machine before you open any cover — mains wiring and standing water share the inside of this cabinet. Bail the tub out before you tip or move it, both because the water will go over the floor and because a full machine is far heavier than it looks. Never run it with a cover off to watch what happens, and keep the drain hose secured before every spin rather than after the first flood.
When to call a technician
Call once the hose is low and unkinked, the filter is clear and the household drain runs freely. Bail the tub out before anyone moves the machine.
Nearest pages of this class
What this page does not cover
This page is written for the appliance class and this symptom, not for one family or model line. Where a family- or model-specific page exists for your unit, it is the more specific answer and it is linked from the sibling list — go there first if your model is named there. Deliberately not here: wiring colours, board part numbers, torque figures and panel-removal sequences, all of which differ by family.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
