A dishwasher not draining water is one of the most common dishwasher problems. Sometimes water remains at the bottom of the appliance after the program finishes, while in other cases the dishwasher stops during the wash cycle and does not drain the water at all. The problem may be caused by something as simple as a clogged filter, but it can also indicate a fault with the drain pump, drain hose, drainage connection, sensor, or electronic control system.
First, check the dishwasher's drain filter. During washing, food particles, grease, and other debris from the dishes collect in the filter. If the filter has not been cleaned for a long time, it may restrict the flow of water. As a result, the dishwasher may not drain properly, leaving water inside the appliance after the program is completed.
A clogged or kinked drain hose can also prevent the dishwasher from draining. When grease, food particles, and other debris accumulate inside the hose, the water flow may become restricted or stop completely. In addition, if the hose is trapped behind the dishwasher or sharply bent, the drainage system may not function properly.
A faulty drain pump is one of the more serious causes. The pump is responsible for removing dirty water from the appliance after the washing process. If a foreign object enters the pump, the impeller becomes jammed, or the pump motor fails, the water will not drain. In some cases, unusual humming or other abnormal noises may be heard when the pump attempts to operate.
The dishwasher's connection to the drainage system should also be checked. If the drain hose is connected to the kitchen sink trap, a blockage in the trap may prevent water from draining out of the dishwasher. In this case, the problem may not be with the dishwasher itself but with the drain or sink trap connection.
Foreign objects entering the drainage system are also relatively common. Pieces of broken glass, small bones, labels, and other small objects may pass through the filter and reach the pump area. These objects can block the pump impeller and stop the drainage process.
A faulty water level sensor may also prevent the dishwasher from draining properly. The sensor provides the electronic control system with information about the amount of water inside the appliance. If it sends incorrect information, the dishwasher may mistakenly determine that the water has already been drained and stop the drainage process too early.
In some cases, the problem is caused by the electronic control board. The control board sends the signal that activates the drain pump. If the relevant section of the board is faulty, the pump may not start even when the pump itself is in working condition. Voltage fluctuations, moisture, and the natural ageing of electronic components can cause the control board to fail.
An error code displayed on the dishwasher can also help identify the cause of the problem. Different brands and models use different error codes for drainage-related faults. The meaning of a specific error code can usually be found in the appliance's user manual. If the same error keeps appearing, professional diagnostics are recommended.
In some dishwasher models, a small amount of water around the filter after the program has finished may be normal. However, if a noticeable amount of dirty water remains at the bottom of the appliance, an unpleasant smell develops, or the next program does not start, there is a high probability of a problem with the drainage system.
In addition to failing to drain water, the dishwasher may also stop midway through a program. If the appliance cannot remove the water from the previous stage, its safety system may prevent it from proceeding to the next stage. Therefore, a dishwasher getting stuck during a program and failing to drain may be caused by the same fault.
Pay attention to the following signs: if water remains at the bottom of the dishwasher, unusual noises occur during draining, the appliance displays an error code, there is an unpleasant smell from the drain, water is leaking, or the circuit breaker trips, do not continue using the appliance. Attempting to disassemble the pump or electronic components of an appliance connected to the electrical supply may cause additional damage and create a safety hazard.
If your dishwasher is not draining water, it is recommended to contact a professional dishwasher repair technician. The technician can diagnose the appliance on site and check the drain filter, drain hose, pump, drainage connection, water level sensor, and electronic control board. Once the cause of the fault has been identified, you will be informed in advance about the required repairs and their cost.