Dyson AM20 Dehumidifier Fails to Drain, Repair Instructions

Understanding the Drain Failure

When a Dyson AM20 Dehumidifier stops draining, it usually indicates a blockage, a faulty valve, or a simple maintenance lapse. Because the device relies on a small internal pump to push condensate into a water tank or directly into a drain hose, any interruption can lead to water backing up, overflowing, or simply not reaching the drain. Before you start digging around, make sure you have the right tools: a flathead screwdriver, a small bucket, a clean cloth, a flashlight, and optionally a flashlight with a red light to preserve night vision.

Safety First

1. Unplug the unit – This is the most critical step. Never work on a powered appliance.
2. Clear the area – Keep the floor dry and free of obstacles.
3. Use protective gear – Gloves are useful to avoid splashing or slipping.
4. Have a drainage plan – Place a shallow tray or bucket under the unit to catch any accidental spillage.

{{IMG:Dyson AM20 dehumidifier}

Preliminary Check: Is the Problem Really the Drain?

Sometimes the unit may appear not to drain, but the issue lies elsewhere:

• Full tank – The dehumidifier will stop pumping if the water tank reaches capacity. Empty it and check for normal operation.
• Air filter blockage – A clogged filter can reduce airflow, causing condensation to build up too quickly. Clean or replace the filter before digging deeper.
• Incorrect positioning – The AM20 is designed to sit on a flat surface. Tilting or uneven placement can interfere with the internal pump.

If these basic checks do not resolve the issue, proceed to a more detailed troubleshooting sequence.

Visual Inspection

Open the rear panel of the unit. The main areas to inspect are:

• Drain hose – Look for kinks, clogs, or disconnections.
• Pump assembly – A damaged impeller or a bent shaft can stop the pump from working.
• Valve – The small valve that directs water to the tank or hose may be stuck open or closed.

If you spot any visible damage, consult a professional. The following steps assume the hardware is intact but a blockage is suspected.

Disassembly: Removing the Drain Hose

1. Locate the hose – The drain hose is usually connected near the rear of the unit, just above the pump.
2. Detach gently – Unscrew the hose connector or pull it out, depending on the design.
3. Pull the hose straight – Avoid twisting; the hose can be fragile.

Tip: Keep the hose in a clean area to avoid contaminating it further.

Cleaning the Drain Hose

A common culprit is a simple blockage of the drain hose by dust, dirt, or even a small piece of debris. Here’s a straightforward method to clear it:

1. Flush with water – Use a garden hose or a clean tap. Direct a steady stream into the hose inlet.
2. Use a small brush – A toothbrush or a bent wire can help dislodge stubborn particles.
3. Repeat until clear – Ensure water runs smoothly to the outlet.

{{IMG:cleaning drain hose}

Checking the Pump and Valve

If the hose is clear and the unit still fails to drain, the issue likely lies inside the pump assembly.

1. Open the pump cover – Usually a removable panel on the rear.
2. Look for impeller damage – The impeller should rotate freely. If it is bent or stuck, the pump will not function.
3. Inspect the valve – The valve should open and close smoothly when the pump runs. If it is stuck in the closed position, it will prevent water from moving to the tank.

How to Test the Pump

• Hand‑turn test – Turn the impeller by hand. It should move smoothly.
• Check for noises – A humming or grinding noise indicates a mechanical problem.

If you discover any damage or obstructions, replace the affected part. The Dyson AM20 uses a proprietary pump, so purchasing the correct replacement part from an authorized dealer is recommended.

Reassembly and Final Checks

1. Reconnect the drain hose – Ensure the connector is tightened but not over‑tightened.
2. Replace the pump cover – Secure any screws or clips.
3. Plug the unit back in – Position it on a stable, flat surface.
4. Turn on the unit – Allow it to run for 30 minutes, observing the water tank or drain hose for normal operation.

If the unit still does not drain, consider the following:

• Water supply line issues – If the unit is connected to a continuous drain line, verify the line is not kinked or blocked.
• Firmware glitch – Unplug the unit, wait a minute, then plug it back in to reset the internal software.
• Professional service – Persistent problems may involve internal electronics or the pump motor itself, warranting expert attention.

FAQ – Quick Answers

When to Call a Professional

If after completing the steps above the unit still fails to drain, it is time to seek professional help. Common reasons for professional intervention include:

• Internal pump failure – The motor or impeller may need replacement.
• Electrical issues – Problems with the pump controller or water level sensor require diagnostic tools.
• Warranty coverage – If your unit is still under warranty, unauthorized disassembly can void it.

Dyson’s support line can guide you through advanced troubleshooting or arrange a service appointment.

Maintaining Drainage Health

Regular maintenance extends the life of your Dyson AM20 and prevents drain issues:

• Clean the water tank weekly – Remove mineral buildup and mold.
• Check the filter monthly – A clean filter keeps airflow optimal.
• Inspect the drain hose every month – Look for kinks or debris.
• Run a cycle with no water load – This helps the pump clean itself and flushes the hose.

By following these simple habits, you’ll keep the drain functioning smoothly and avoid future headaches.

Final Thoughts

A failing drain in a Dyson AM20 Dehumidifier is usually a solvable problem. Start with the simplest steps—unplug, check the tank, inspect the hose—then move to more detailed inspections of the pump and valve. If you are comfortable working with small appliances, most issues can be fixed at home. However, always prioritize safety and do not hesitate to contact a professional when the problem appears beyond basic repair.

Remember that prevention is key: regular cleaning and proper operation will keep the dehumidifier draining efficiently for years.