Do not heat the water in the dishwasher

Most dishwashers are connected only to the cold water supply system, so the operation of the heating element is very important, otherwise the dishes will simply not be washed. If the "dishwasher" does not heat the water, this will be noticeable immediately after the completion of the washing cycle, which means that the problem urgently needs to be fixed. It is not necessary that in this case we are talking about a malfunction of the heating element or temperature sensor, there are other reasons that we will need to talk about in the framework of this article.

Why does the water in the dishwasher remain cold?

Why does the dishwasher not heat the water? To answer this question, it is necessary to approach the solution of the problem systematically, namely, to consider the relationship of all units and sensors of the dishwasher and decide what can (at least indirectly) adversely affect the operation of the heating element? The main reasons why the water in the "dishwasher" remains cold is three:

• the heating element itself is faulty;
• malfunctioning thermostat;
• defective control unit element.

In addition to the main reasons why the water in the car does not heat up, there are additional ones. At first glance, it seems that these breakdowns can not have any effect on thermocouples, but this is actually not the case. Let's look at the auxiliary reasons why the water in the tank of the dishwasher does not heat up.

1. The dishwasher is connected in violation of the instructions.
2. There was a strong blockage in the trash filter.
3. User error while choosing washing mode.
4. Defective pressure sensor.

A pressure sensor helps control the circulation of water in the dishwasher. If the pressure sensor is defective, water can constantly circulate in the dishwasher, which in turn can lead to self-drainage. Under these conditions, even if the heating element is in working condition, it simply does not have time to heat the water and the dishwasher is forced to use cold water to implement the washing program. The problem is solved by replacing the pressure sensor, repair in this case is useless.

Note! Before replacing the pressure sensor, you can try to clean its contacts, as well as inspect the electrical wiring that supplies this sensor.

If the dishwasher stops heating the water, the cause may be a clogged trash filter. Some people will ask, what does the garbage filter have to do with it, and what does it have to do with the heating element? We will answer - the most direct.

The fact is that during the implementation of the washing program, water should circulate normally between the tank and special tanks, respectively, the heater maintains the temperature of the water, ensuring the normal quality of washing dishes. And if the filter is clogged, then the circulation is disturbed. This leads to the accumulation of water in the tank, the system will be forced to replenish water (which does not return back from the tank with dishes to the tank) from the water supply system, and it is cold, accordingly - the heating element simply does not have time to heat it.

To identify this problem, you need to look into the tank during washing. Under normal conditions, water should not linger there. If water builds up in the tank, the waste filter must be cleaned urgently. After this, the water circulation will resume, and it will be possible to count on eliminating problems with heating the water, unless, of course, a simultaneous breakdown of the thermistor or heating element occurs, and this is also quite possible.

If the water does not heat in a new dishwasher, then in this case the problem may be that it was not correctly connected to the sewer. What is the matter here? If the drain hose of the dishwasher is connected correctly to the sewer pipe, the master makes two elbows (smooth bending of the hose): one at the very base of the dishwasher, and the other at the point where the hose connects to the siphon.

Important! These two knees are needed so that there is no "siphon effect", that is, water does not go from the sewer pipe back to the dishwasher.

Accordingly, if normal drainage of water into the sewer is impossible, then water cannot circulate in the dishwasher either. This will lead to the fact that the water temperature will differ from that set by the program, and this is in the best case. At worst, the water will remain cold, and the user will “sin” on the heating element, although it has nothing to do with it. The problem is solved simply - the connection to the sewer is done according to the instructions, and the machine starts to work normally.

Sometimes a Bosch (or another brand) dishwasher does not heat water for a very prosaic reason - the user chose the wrong washing program. This rarely happens, because in modern "dishwashers" there are not so many programs to get confused in, but it does happen. Recipe - read the instructions and learn how to choose the right washing program for a specific volume and category of loaded dishes.

Check and repair of temperature sensor, control module

Now let's move on to the main reasons why the dishwasher does not heat water. Let's start with the temperature sensor. For some reason, this element has become a kind of weak point of most brands of dishwashers, including Bosch. Therefore, for starters, let's decide how to understand that the temperature sensor really broke, and not something else, and that it requires replacement? We act like this.

• We take screwdrivers, pliers and a multimeter.
• We disconnect the dishwasher from the water supply, sewage and mains (do not forget to block the water at the outlet of the pipe).
• We take out baskets for dishes from the Bosch “dishwasher” tank.
• We take out the lower sprayer, take out the trash filter, remove the mesh and unscrew the two fasteners located under it.
• Turn the dishwasher upside down and unscrew the plastic (or metal) side mounts.
• We disconnect the drain pipe from the plastic block with a heating element and raise the bottom of the dishwasher up.
• The sensor is located in the housing of the heating unit, this is necessary so that the water temperature is accurately monitored by the control module. Disconnect the wires from the contacts of the temperature sensor.
• We clean the contacts and measure the resistance of the temperature sensor.
• We take out the burned-in temperature sensor, change it to a new similar one, and then collect the “dishwasher”.

Important! In this case, the temperature sensor is not always the problem, sometimes the wiring is faulty, and in rare cases even the control module element.

In about 1% of cases, it happens that the heater is in good condition, the temperature sensor also works and the wires are in order. Moreover, we have already checked the car and for clogging, and checked whether it was installed correctly, checked the pressure sensor - everything works fine, but the temperature of the water in the cold water pipe and the temperature in the dishwasher still remains the same. There is a possibility that in your “dishwasher” the control module has broken down, namely not the entire module, but some of its triacs.

For our part, we categorically do not recommend climbing to the control module on your own, without having the skills to work with electronics. The risk is great to harm her even more, and buying a replacement part will be very expensive. Ask a specialist for help.

How to check and replace the heating element?

If the cause of the fact that the water in the dishwasher is not heating is a burned-out heater, you need to prepare for an expensive repair, but first you need to make sure that the reason for the breakdown is really heater. The problem is that the heating element of the dishwasher Bosch in some cases is flowing and in which case, it must be replaced by a module, which makes repairs more expensive. Check and replacing ten in the dishwasher must be done in a strictly defined order. Read about how to do this in the article of the same name on our site.

In conclusion, we note that if the water does not heat up in the dishwasher, then this is not a reason for panic. First you need to delimit the circle of possible malfunctions that led to this result, and only then take for a systematic search for the problem point. Good luck in the repair!