The dishwasher worked in the usual mode for many months, but suddenly stopped in the middle or at the end of the cycle and refused to drain the water. Do not rush to despair and look after new equipment. The reason may be a simple malfunction that you can fix yourself. In the article, we will consider why the Bosch dishwasher does not drain the water and what to do about it.
Causes of water accumulation in the pan
Why doesn't the water drain? There are several scenarios. The simplest ones are clogging or squeezing the drain hose. Check if it is evenly located - maybe it is bent or turned out to be transferred by some object.
The sewage system at the junction with the drain hose could clog.
Other causes of stagnation of water in PMM Bosch:
- Drain filter clogged. Food debris, small debris fall into the filter during washing. It is advisable to inspect the part for blockage after each cycle.
- Clogged pipe, siphon. Check all parts of the drain.
- The pump is broken, or its impeller is jammed. Despite the fact that the dishwasher is equipped with a filter, small particles penetrate deep into the equipment, blocking the work of parts.
- Pressostat sends incorrect readings. The level sensor is responsible for the amount of water in the hopper. If the pressure switch fails, the board “does not know” that there is water left in the chamber and does not start the pump.
- Defective control unit. He directs the work of all mechanisms in the car. The pump triac may have failed. Then the pump does not receive a signal to turn on and pump out water.
In case of such malfunctions, the DTC E24, E25 or “END” may be displayed on the machine display.
We will figure out what to do if there is water in the dishwasher.
DIY PMM Bosch repair
Begin testing with a drain hose and sewer. Disconnect the hose, take a deep container and lower it into it. Run the drain mode. If water spills freely, then the cause is a blockage in the sewer. You can clean it with special powders or call plumbing.
How to drain the water from the hopper? Through the drain hose, as described above, either substitute a container and drain off the residues by tilting the dishwasher. Automatic draining is carried out in each model in different ways, the steps are described in the instructions. Here are a few options:
- turn the ratchet switch and the drain valve will open;
- in the PMM series SRV, SGV, you need to reset the programs and close the camera door more tightly;
- for SMV, SPV models, a three-second press of the “Start” key is triggered.
Then open the hopper door and unscrew the drain filter in the pan. Rinse it under pressure from the tap, additionally clean the mesh with a brush.
Next, inspect the impeller of the pump. How to do it:
- Behind the filter is a drain pump. There is often water in this hole - pump it out with a sponge.
- If there are bolts, unscrew them.
- Pull the cover to the side and toward you.
- After removing the flap, inspect the impeller. Have you noticed that threads, hair, which block the operation of the mechanism, are wound around it? Then put on gloves and clean the impeller.
If the problem was not noticed immediately, the drain pump worked for a long time, trying to pump out the water. As a result, the part could burn out.
How to check and replace the pump:
- Open the chamber door and remove all the basket for dishes.
- Flip the PMM onto the back wall.
- Remove the bottom panel.
- A drain pump is attached to the circulation unit on the side.
- Disconnect the wiring from the pump.
- Unscrew the fixing screw.
- Scroll the part counterclockwise.
Now inspect the pump for blockage. Diagnostics of the electronic part is carried out with a multimeter. If you notice a problem, then it is better to install a new part.
Is the pump working as expected? Inspect the pressure switch - in Bosch dishwashers it is also attached to the engine. The part looks like a plastic box with a tube and a pressure reservoir. How to replace the pressure switch in the dishwasher, read the article.
The most unpleasant breakdown is the failure of the control module. A breakdown can occur for various reasons: a sudden power surge, moisture, short circuit. Failure can fail not the entire unit, but its individual elements. Then the board can be repaired, but only a specialist should do this.
How to get to the electronic unit:
- fully open the hopper door;
- unscrew the perimeter screws from the inside;
- close the door and remove the outer panel;
- disconnect the wiring from the control board;
- Inspect the unit for damage.
Now you can contact the master. You should know that replacing a module is not always cheaper than buying new equipment, especially if the dishwasher has already served 10 years. But if you choose spare parts, buy only original accessories with which the dishwasher will work for many more years.