it's making a loud gurgling or bubbling noise, almost like water is running through it, is that normal?

Diagnosis

The gurgling, bubbling, or "trickling water" sound you are hearing in your Midea MAD50C1ZWS is typically the result of refrigerant transitioning between liquid and gas states as it moves through the evaporator and condenser coils. This process is known as "refrigerant migration." When the compressor kicks on or off, the pressure changes rapidly, causing the refrigerant to bubble through the expansion valve and capillary tubes. In this specific 50-pint model, the noise is often more pronounced because the unit utilizes a high-efficiency compressor that creates significant pressure differentials. If you hear this sound primarily during the first 2-5 minutes of a cycle or immediately after the unit reaches its target humidity level and shuts down, it is a normal characteristic of the thermodynamic cycle. You can confirm this is normal if the unit is still actively pulling moisture from the air and filling the bucket (or draining through the hose) at a consistent rate. However, if the gurgling is constant, loud enough to be heard from another room, and is accompanied by a "hissing" sound, it may indicate a partial blockage in the refrigerant lines or a leak that has lowered the system pressure, causing the refrigerant to flash into gas prematurely.

How to Fix It

Since this is generally a normal operational sound, there is no mechanical "fix" required. However, you can minimize the perceived noise and ensure the system is running at peak efficiency by following these stabilization steps:

1. Level the Chassis: Place a bubble level on top of the unit. If the unit is tilted forward or backward, the refrigerant and oil in the compressor may not distribute evenly, increasing the gurgling sound. Adjust the feet or the surface until the unit is perfectly level.
2. Clear the Air Intake: Ensure there is at least 12-18 inches of open space around the back and sides of the unit. Restricted airflow causes the coils to get too cold, which can lead to excessive refrigerant bubbling and potential icing.
3. Clean the Filter: Remove the washable filter from the rear. Rinse it under warm water with mild soap, dry it completely, and reinstall. A clogged filter forces the compressor to work harder, increasing the velocity and noise of the refrigerant flow.
4. Set a Constant Humidity: Avoid switching the unit frequently between "Dry" mode and a specific humidity percentage. Set it to a steady 45% or 50% to allow the compressor to find a steady rhythm, which reduces the frequency of the loud startup/shutdown gurgles.

If That Didn't Work

If the noise is constant and the unit is no longer dehumidifying effectively, try these advanced troubleshooting steps:

• Perform a Hard Power Reset: Unplug the unit from the wall outlet for exactly 30 minutes. This allows any trapped refrigerant to settle and resets the internal control board. Plug it directly into a wall outlet rather than a surge protector, as these high-wattage compressors can experience voltage drops that cause erratic compressor behavior and noise.
• Check for Coil Frosting: Remove the filter and look at the metal evaporator fins. If you see a layer of ice or frost while the unit is running, the gurgling is likely caused by refrigerant struggling to move through a frozen block. Turn the unit off and let it defrost completely for 24 hours before restarting.
• Inspect the Drain Path: Ensure the bucket is seated perfectly flush against the chassis. If the bucket is slightly skewed, water may be trickling down the internal housing rather than flowing directly into the tank, mimicking the sound of refrigerant gurgling.
• Verify Refrigerant Charge: If the compressor is running (you feel vibration) and the gurgling is constant, but the coils are not getting cold to the touch, you likely have a refrigerant leak. Since this is a sealed system, this requires a certified technician to check the pressure levels.

Heads Up

• Never use a thin extension cord with this model; the MAD50C1ZWS requires a dedicated circuit to prevent compressor strain and abnormal noise.
• Clean the filter every two weeks during peak summer months to prevent the evaporator coils from freezing over.
• If you use the continuous drain hose, ensure the hose has a consistent downward slope; any "u-bend" or trap in the hose will cause water to back up and create a loud bubbling sound.
• Avoid placing the unit in rooms below 60°F (15°C) unless you are using a model with a built-in heater, as low ambient temperatures cause the refrigerant to behave erratically and increase noise.