A washing machine relies on precise internal communication to perform each stage of the cycle correctly. One of the most critical components responsible for that accuracy is the water level detection system. When your washer stops recognizing how much water is inside the drum, the entire wash cycle becomes unreliable. You may notice the machine overfilling, underfilling, stopping mid-cycle, refusing to start, or showing unexplained error codes. All these symptoms often point to a single issue: a malfunctioning pressure sensor or a kinked pressure hose.
Understanding how these components work and what happens when something disrupts them can help you act quickly, prevent damage, and avoid costly repairs in the future.
How the Washer Detects Water Level
Inside every modern washer, there is a pressure sensor (sometimes called a water level switch) that communicates with the control board. Its role is simple but essential: it measures the air pressure inside a small hose that connects to the bottom of the tub. As the water level rises, the air pressure increases, and the sensor interprets this change to determine how much water is present. This information allows the washer to fill correctly, maintain balance, use the right settings for the cycle, and prevent overflow. When the sensor or the hose malfunctions, the entire logic of the machine is disrupted.Signs the Washer Is Not Detecting the Water Level Correctly
Several symptoms may appear, depending on the nature of the malfunction:- The washer fills with too much or too little water
- The machine refuses to start a cycle
- The cycle stops unexpectedly
- Water continues running even when the drum is full
- The washer drains immediately after filling
- Repeated error codes related to water level or pressure
- Clothing comes out poorly washed because the water level was incorrect
Common Cause 1: A Malfunctioning Pressure Sensor
Pressure sensors can fail due to age, moisture damage, electrical faults, or internal corrosion. When this happens, the sensor sends incorrect signals to the control board. For example:- It may think the drum is empty when it is actually full
- It may detect overfilling that isn’t happening
- It may fail to switch between water levels
- It may misread pressure changes and cause cycle interruptions
Common Cause 2: A Kinked or Blocked Pressure Hose
In many cases, the sensor itself is fine, but the hose connected to it is not. The pressure hose can become kinked, twisted, clogged with detergent residue, or clogged with lint. When airflow inside the hose is restricted, the sensor cannot read the pressure correctly. A kinked hose may cause:- Overflow due to inaccurate readings
- Underfilling because pressure does not rise correctly
- Sudden draining because the sensor thinks the drum is too full
- Intermittent errors that appear only during certain cycles
Why You Should Not Ignore These Issues
Problems with water level detection are more serious than they appear. Incorrect water levels can cause the machine to overwork, strain the motor, waste water, and damage internal parts. Ignoring the problem may lead to:- Flooding
- Drum imbalance
- Premature wear of the motor
- Failure of the control board
- Mold growth from leftover water
- Safety hazards due to electrical moisture exposure