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Samsung WW90 washing machine won't drain – diagnosis and fixes

SAMSUNG WW90 range · freestanding washing machine · based on 105 similar repairs

Diagnosed by Sean McCauley · SMC Services · Last verified 10 May 2026

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Likely causes (Samsung freestanding washing machine):

Problem summary

Your Samsung WW90 is retaining water at the end of the cycle and won't empty. The drum may be full of standing water or the machine stops mid-cycle. This is one of the most common faults in the WW90 range and often has a straightforward cause.

Likely causes

Based on our repair records, the most common culprits are:

Pump blockage or failure (around 62% of cases) The drain pump is responsible for pushing water out of the machine. It can become blocked by fluff, fabric fibres, or small objects, or it can wear out over time and stop working entirely.

Drain hose kink or blockage (around 29% of cases) The hose carrying water from the pump to your waste outlet can become kinked, crushed, or blocked by detergent sludge or debris.

Filter clogged (common contributing factor) The pump filter catches lint and small objects. If it's full, water cannot flow through properly.

Control board fault (less common, around 15% of cases) A fault in the printed circuit board (PCB) can prevent the pump from receiving the drain signal, even if the pump itself is working.

What you can try yourself

Before calling an engineer, check these points. Most are quick and cost nothing:

  1. Check the pump filter – Usually located at the bottom front of the machine behind a small panel. Turn off and unplug the machine, then open the filter access panel. You'll find a cylindrical or cartridge filter. Unscrew or unclip it and empty any debris. Rinse it under a tap and refit.

  2. Inspect the drain hose – Pull the machine away from the wall slightly (with the power off) and look at the hose running from the back to your waste outlet. Check it isn't kinked, crushed, or blocked. If it's very dirty inside, you may need to disconnect and flush it through with water.

  3. Look behind the drum – If you can safely access the pump area (after unplugging), check for fluff, hair, or small items like coins or buttons that may have been sucked into the pump inlet.

  4. Test the pump – If you're confident working with appliances, the pump itself can sometimes be accessed and tested. However, if the pump needs replacing, this usually requires partial dismantling.

If the filter is clear, the hose is straight and unblocked, and water still won't drain, the pump is likely faulty or the control board is not sending the drain signal.

When to call SMC Services

If your DIY checks don't solve it, or if you're not comfortable opening the machine, a qualified engineer will quickly identify whether the pump needs replacement or if the fault lies with the control board. Pump replacement is a straightforward wear-part fix on the WW90 range.

If you're in Northern Ireland, SMC Services can usually book a repair within 2-3 working days.

Step by step

  1. Empty the filter and hose. Unplug the machine. Open the pump filter panel at the base, unscrew the filter, and empty debris. Check the drain hose behind the machine for kinks or blockages. This clears the most common causes.
  2. Run a test cycle. After cleaning, plug in the machine and run a short drain cycle (or a quick rinse programme that includes drainage). If water now drains, you've found the cause. If not, move to the next step.
  3. Inspect the pump inlet. If you're confident with appliance access, you can check behind the drum for lint, hair, or small objects caught at the pump inlet. Any blockage here will stop the pump working. Do not attempt this if you're unsure how to safely access the area.
  4. Check for electrical faults. If the filter and hose are clear and water still won't drain, the pump motor itself may be faulty or the control board may not be sending a drain signal. These faults require an engineer to diagnose and repair safely.

Frequently asked questions

Can I run a hot cycle to clear a blocked pump?
Running a maintenance cycle or hot wash may help shift mild sludge buildup in the hose or filter, but it won't clear a mechanically blocked pump or a failed pump seal. If the machine won't drain at all, running more cycles risks water damage to surrounding areas.
Is the drain pump an expensive part?
The pump is a wear part and is typically affordable. Labour to fit it will depend on how accessible the pump is in your model. Our engineers can give you a cost estimate once they've diagnosed the fault.
My machine drains very slowly but does eventually empty. Is this the same fault?
Slow draining often points to a partial blockage in the filter or hose, or a pump beginning to fail. It's worth clearing the filter and checking the hose, as these can improve flow significantly.
Could a blocked coin trap cause this?
Many machines have a separate coin trap or debris trap before the pump. If this is full, water flow to the pump can be severely restricted. Check your manual for its location and empty it if accessible.
Do I need to replace the pump myself or call an engineer?
If you have experience with appliance repair and are confident dismantling your machine, you can replace the pump yourself. Otherwise, an engineer will remove, fit, and test the replacement to ensure it works correctly.

Get this fixed

The parts most often needed for this repair — order direct:

Fits your WW90 Samsung Drain Pump (DC31-00181A) £43.91 SMC02398 View part → Fits your WW90 Samsung Drain Pump (DC31-30008D) £47.65 SMC05796 View part → Fits your WW90 Samsung Main Pcb (DC92-01640G) £99.23 SMC05912 View part → Fits your WW90 Samsung Main Pcb (DC92-01768D) £86.82 SMC10912 View part →
Browse all spares

Prefer a pro? A local appliance engineer can carry out this repair. SMC's own repair service covers Northern Ireland only. The parts above ship UK-wide.

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About the data on this page

This page draws on 105 similar repairs from across 29 years of SMC Services records — over 116,000+ appliance repairs in total since 1997. The likely-cause percentages above are computed directly from the engineer reports we filed for this brand and fault, and we update them as new repairs come in.

SMC Services Ltd · Registered in Northern Ireland, Co. NI628091 · Domestic & Commercial Appliance Repairs.