The devices responsible for ensuring that everything works smoothly are control elements represented by electronic units and sensors. One of the most important parts of any washing unit is the pressure switch.
If the water level sensor is faulty, the control module of the washing machine processes the signal incorrectly or does not receive it at all from this device. In such a situation, the water level in the tank is not controlled, and therefore underfilling or overflowing occurs. All signs of a malfunction of this sensor will be described below.
What is a pressure switch
When wondering what a water level sensor is, you need to understand that any process related to the supply of water to the washing unit must be strictly regulated by a given program. According to the principle of operation, the pressure switches of washing machines Lg, Samsung, Electrolux, Candy, Ariston or any other brands do not differ, but there may be differences in design, appearance and characteristics. This device looks like a small plastic piece, usually round in shape, with electrical wiring connected to it and a tube from the washing tub tank.
The pressure switch in a washing machine is a device that controls the water level in the tank, without which the operation of any unit is simply impossible. The element is small in size, and its replacement does not require major capital investments, but the importance of this part is enormous.
Appearance
The design of the simplest electromechanical unit is a cylindrical plastic case, inside of which there is an air chamber with a diaphragm, tubes, an inductor with a core and a contact group of conductors.
The complexity of the sensor depends on the number of washing programs in the washing machine . Pressure switches differ for different models of equipment, and this fact should be taken into account if it is necessary to replace a failed sensor.
The installation location of the pressure switch differs for different models and directly depends on the design of the machine.
- For machines with classic laundry loading and a steel drum, the sensor is located under the top cover.
- For models with top loading of laundry items, the pressure switch is installed below the tank.
- For washing machines equipped with plastic drums, the sensor is located in the rear of the housing.
Option for the location of the pressure switch in the washing machine
Operating principle of the sensor
The operating principle of the water level switch of a washing machine is based on the effect of pressure on a special membrane (diaphragm). When water is drawn into the tank of the washing unit, water fills the compression chamber and pressure corresponding to the level of the collected water is injected into the sensor housing through a special tube.
The compression chamber is usually built into the drain pipe. The pipe itself is connected to the tank and the volute from the drain pump using special clamps. There are cameras soldered directly into the tank itself. It happens that these cameras become clogged with slurry and dirt over time!
When pressure is applied to the membrane, the contacts close and open, as a result of which a signal about incoming water is sent to the control module. There are several types of pressure switch: pneumatic (mechanical) or with an oscillating circuit (electronic), in this case the mechanical principle will be described. They are also divided into single-chamber and double-chamber.
Double-chamber pressure sensors are specially developed for washing machines with small and large loads. When the load is low, one membrane is activated and water is supplied in a minimum amount. When the drum is heavily loaded, the second membrane is activated, the contacts close and the control processor gives a command to supply the maximum amount of water.
As a rule, the membrane installed inside the sensor is made of rubber or elastic polymer and is designed for repeated on and off cycles. The operating principle of the pressure switch combines the sequential influence of air pressure on the mechanical part, above which the electrical contacts are located, and a direct electrical impulse on the control processor of the washing unit.
Adjustment process
It is not necessary to seek the help of professionals to set up the liquid level sensor; repair work can be done independently. It is necessary to strictly follow the instructions below and perform all actions carefully, with extreme caution. To adjust the level sensor of a washing machine, you need to follow the following algorithm:
- disconnect the automatic machine from the power supply and water supply;
- remove the pressure switch by unscrewing a pair of bolts holding it and carefully disconnecting the wires supplying the part;
- look for special screws designed to tighten and loosen the internal contacts of the device;
- remove any remaining sealant from their surface.
These manipulations can be called preparatory; the main work of setting up the pressure switch remains to be done. Next, using the cleaned screws, you need to try to catch the moment of approaching and opening the contacts with your own hands. In this case, you will have to use the well-known “poke method”, since a non-professional does not have special devices that allow you to establish the moment of closure. You need to do this:
- turn the first screw half a turn, connect the sensor to the machine, turn on the machine and start the washing mode;
- if in your case the required volume of water was not initially collected, but now there is more of it, then the right path of action has been chosen. Unscrew the screw further in the same direction, then fill part of the part with sealant;
- if unscrewing the bolt has the opposite effect, turn it in the opposite direction by one or one and a half turns.
The main task when adjusting the pressure switch is to set the optimal parameters for its operation so that the sensor is triggered at the right time and clearly determines the volume of water collected in the tank.
After the screws are screwed to the desired position, be sure to treat them with silicone sealant to prevent subsequent loosening of the fasteners.
Signs of a malfunctioning pressure switch
As with any element of a washing unit, malfunctions can occur in the water level sensor, leading to malfunctions of the entire washing unit. This is expressed in the following signs:
- the washing process begins in the absence of water;
- water is supplied to the tank in too much or too little quantity;
- after the wash is completed, water is not removed from the tank;
- the laundry spinning program is not processed;
- There is a periodic pumping out of dirty water and supply of clean water in the rinsing mode, which is not typical for normal operation;
- malfunctions of the washing machine in all washing programs.
In addition, due to the lack of water in the tank and the heating element being turned on, smoke and a burning smell may appear. Typically, such inclusion ends with the replacement of the heating element. A faulty sensor can also lead to failure of the electric motor due to constant overload on it, since more water is often drawn into the tank than the required level.
Self-diagnosis of the pressure indicator
Having the ability to handle a screwdriver, you can try to clarify the cause of the machine malfunction yourself: the listed problems are not always caused by a breakdown of the pressure switch. A mandatory condition for carrying out work is safety.
Before starting the diagnosis, the SMA cord and plug are removed from the power outlet. To get to the control device, you need to perform the following operations:
- on the back wall of the machine, find the screws that secure the top panel, unscrew them, slide the cover towards you - a level sensor is located under it;
- inspect the pressure switch in order to detect external signs of a malfunction: the integrity of the electrical wires, whether the hose has become disconnected from the fitting of the device due to vibrations;
- dismantle the sensor by unscrewing the fastening screws, remove the clamp holding the rubber tube and disconnect the wires;
- clean the hose and fitting from blockages, remove oxide deposits from the contacts and terminals.
After making sure that there is no external damage, proceed to checking the device itself. When disconnecting the wires from the block, they are marked to remember the order of reconnection.
Where is the pressure switch located?
In washing machines from most manufacturers, the sensor is installed on a bracket in the upper part of the body on the side wall, however, in each specific case, you can find out where this device is located only by removing the top cover or side trim of the unit. Very rarely, on vertical types of machines, the pressure switch is located at the bottom of the unit.
A distinctive feature that makes it easy to find the sensor is a small-diameter tube connected to it, usually made of rubber or polyvinyl chloride.
Replacing the pressure switch
If checking the water level switch shows that it is faulty, then replacing it in most cases does not cause any particular difficulties. Therefore, you can change this device yourself, without resorting to the help of specialists. Repairing the device itself is not only impractical, but also useless, since the case is non-separable, any attempt to get to the internal parts will lead to a violation of its integrity. Some types of water pressure sensors must be opened, but this is a rather lengthy process and requires some competence in this area.
Replacing the pressure switch in a washing machine begins with disconnecting the vacuum tube and electrical contacts. By loosening or unscrewing the mounting bolts, remove the sensor. Reinstallation of the device is carried out in the reverse order of dismantling. Although the vast majority of sensors are similar in appearance, it must be taken into account that this element is configured for a specific model and brand of washing unit.
When carrying out all types of work, safety measures must be strictly observed. Before starting work, it is imperative to disconnect the plug of the washing unit from the power outlet.
Prevention
In order for the pressure switch in the Ariston, Electrolux (Electrolux) washing machine to work for a long time and control the required pressure, it is recommended:
- Follow all operating instructions of the washing machine manufacturer;
- Eliminate the slightest malfunctions promptly and competently;
- Protect the unit from voltage surges in the network using special voltage stabilizers;
- Use hard water softeners;
- If the washing machine is still under warranty, it is better to have it repaired by a service center;
- Regularly check the drain hose filter for dirt, foreign objects, and deposits;
- Carry out a preventive examination and preventative washing once every 12 months;
- Repairing the washing machine pressure switch yourself should only be done if you have a certain level of knowledge and experience.
- How to wash a bathroom curtain
- How to remove glue from clothes
How to check the pressure switch yourself
The water level sensor in the washing machine tank can be checked for functionality at home. To do this, it must be dismantled. Carefully inspect the pressure switch housing and vacuum tube for mechanical damage (cracks, chips, abrasions). Carefully check the tube and inlet fitting for blockages, and if there are any, clean them with a plastic stick or soft wire.
The pressure switch can be checked for functionality by blowing air into its housing using a small hose identical in diameter to the standard one. To do this, attach the hose to the inlet fitting and blow lightly into it several times. In connection with the pressure force, characteristic clicks should be heard inside the housing. The number of clicks depends on how many water levels a particular model of washing unit provides. Their absence indicates a malfunction.
The second way to check the water level sensor is to measure it with a multimeter. This method allows you to be almost one hundred percent sure that the pressure switch is faulty. By connecting the device to the pressure switch, you need to measure the resistance. If the resistance does not change when air is blown into the device body, you can safely send the faulty element for scrap.
In order to avoid undesirable consequences for the entire washing unit as a whole, it is necessary to carefully monitor its operation, and if the slightest malfunction is detected, take the necessary measures. By replacing a relatively inexpensive pressure switch in advance, you can extend the life of the entire washing machine for a long time.
How much do the services of a master cost?
If you were unable to cope with replacing the pressure switch yourself, you need to call a specialist. You can find it through an ad on the Internet or in a newspaper. It is possible that someone you know used the services of such a specialist and was satisfied with his work.
To minimize the risk of encountering scammers, it is better to contact a large company that repairs household appliances. Such organizations have their own website, and reviews of their work are always available on the Internet.
Reputable workshops can provide free visit of a technician and diagnostics of the device , and discounts are often provided to pensioners and low-income citizens.
The cost of replacing the pressure switch is about 1,600 rubles. This procedure does not take more than an hour. Reputable organizations provide a guarantee for all work performed, which should not be less than 6 months.
Prices for the services of a master may vary depending on the locality . However, they should not be 2-3 times more expensive. If a specialist asks for too high a price, you should not trust him.
Private craftsmen can offer more favorable terms of cooperation. However, when calling such a repairman, you should not be alone with him. If he demands money for a service he did not perform, you need to threaten to call the police.
Everything about repairing Samsung washing machines is in this section.
Setting the washing machine pressure switch
Along with the serviceability of all elements of the sensor, its precise adjustment is also of utmost importance. It must operate clearly at certain pressure levels, sending the necessary signals to the central control processor. The amount of water supplied to the tank depends on this, which is different at each stage of washing.
Accurate calibration of pressure switches is carried out at the manufacturer's factory using special ohmmeter devices, and under normal conditions no additional adjustment is required. Washing machine repair technicians not only do not recommend, but also categorically deny the possibility of adjusting the pressure sensor at home.
On the adjusting bolt of almost any pressure switch there is a seal, the integrity of which must not be violated. Even if you simply insert a screwdriver and turn the bolt half a turn, and then turn it the same half a turn in the opposite direction, the fine adjustment will be lost. In this case, no one can guarantee the normal operation of the washing unit.
Experiments with adjusting the water level sensor, as a rule, lead to failure of the heating element or the entire unit as a whole. If the cause of malfunctions in the washing machine is indeed the pressure switch, it is replaced entirely, and it is best if this operation is carried out by a service center technician, followed by high-quality diagnostics.
Where and how much to buy a new part?
You can purchase a new water level control sensor at a specialized service center or store, or order it online. Sometimes the part is available from private craftsmen who repair washing machines.
However, very often they sell used pressure switches that were removed from other devices. Such a sensor can work for several years or several days. There is no guarantee for it.
Before you make a purchase in a store, you need to make sure that the new sensor is exactly the same type and name as the previous one. It must match the make and model of your washing machine.
This parameter directly affects the price of the sensor and varies from 900 to 2000 rubles.
The newer and more expensive the washing machine, the higher the price of all components will be.
When buying a sensor, you need to get a receipt from the seller . If it turns out to be faulty, the retail outlet must replace it.
