DIY repair of heating elements

An electric boiler is an effective solution to the problem of hot water supply for a private house. Such equipment, however, like any other, breaks down periodically.

If serious breakdowns have to be eliminated in a service center, then any more or less experienced craftsman can perform a small repair of the water heater with his own hands.

To minimize problems with the device, you should study its design and principles of operation. Usually, in private households, not flow-through, but storage models are used, which make it possible to use electricity more efficiently. Such a device consists of a heat exchanger tank, inside which a heating element is installed - a heating element, connected to the power supply.

An important part of the device is the thermostat. This element allows you to maintain a constant water temperature inside the storage tank. The water is piped to the heat exchanger. If its temperature is too low (and this is usually the case), then the thermostat gives a signal and turns on the heating element.

The water is heated until it reaches the required temperature. After that, the thermostat works again and turns off the heating element. Hot water is taken from the tank and replaced with cold water, the heating process is repeated over and over. This is a general diagram of the device and operation of a conventional storage water heater.

Flow models are arranged somewhat differently. They do not heat a static volume of water, but a stream. They use more powerful heating elements that start working when the water is turned on and stop when it is turned off. To study in more detail the operation and structure of a particular model, you need to carefully familiarize yourself with the accompanying technical documentation.

The heater tank is a sturdy stainless steel container, one or two millimeters thick. No matter how resistant this material is to corrosion, nevertheless, these processes periodically arise and develop, which leads to the flow of water from the device. One of the most common causes of such breakdowns is electrical corrosion.

To prevent it, you need to regularly, i.e. Replace the internally mounted magnesium anode annually. This element is specifically designed to prevent electrical corrosion. Over time, it wears out, and the owners of storage tanks lose sight of replacing this important part.

As a result, the tank, which has served well for some time, suddenly starts to leak. The incorrect state of the magnesium anode can also affect the state of the heating element. The outside of the storage tank is usually enclosed in a metal or plastic housing, and it also has a heat-insulating shell that prevents heat loss.

Damage to the outer shell and insulation is rare, usually due to careless handling of the device. Cracks and chips on the body of the water heater may not interfere with its operation, but this will lead to a deterioration in the properties of the heat insulator, and will negatively affect the functioning of the device as a whole.

Cold water inlet and outlet pipes - for hot water usually do not cause any problems if the installation of the heater is done correctly. Usually, a water heater is equipped with two thermostats, one of which is designed to control the water temperature, and the second monitors the state of the first device.

Sometimes a third thermostat is also used, which determines the good condition of the heating element. In any case, the broken thermostat will have to be completely replaced. There are capillary, rod and electronic types of thermostats.Their design is different, but the principle of their work is the same.

The insulating gasket not only serves to seal the connection between the elements of the water heater, it is also necessary as an electrical insulator. It is recommended to replace this element regularly at every maintenance of the water heater.

The thermostat shows exactly what temperature the water inside the device is heated to. If this element breaks down, the water heater will still perform its functions, although data on the degree of heating will not be received.

Breakdown of heating elements is a typical problem for both flowing and storage water heaters. This element works under high stress and therefore wears out quickly. If the power supply is connected, but the water in the tank does not heat up, most likely the problem has arisen with the heating element.

First, you should check if electricity is supplied to the heating element and the thermostat. In the places where the cable is connected, the presence of voltage is checked with a tester. If there is no voltage, you may need to replace the cable itself or check for a power outage throughout the house.

If there is electricity and the cable is working properly, then problems have arisen with the heating element, which will have to be replaced, or with the thermostat. To figure out what exactly broke, you need to remove the thermostat and check it with a tester. Testing the health of the heating element is carried out as follows. First, the measuring scale of the device is set to the interval of 220-250 V. Then the resistance is measured at the terminals connecting the heating element to the mains.

If there is voltage, disconnect the heating element from the network and check the potential at the terminals of the heating element. Lack of response from the tester will indicate that the device is defective. If there is a reaction, you need to continue the diagnosis. First, disconnect the water heater from the power supply. Then the heating element is disconnected from the thermostat so that the contacts of the heating element remain not isolated.

Tester contacts are applied to them and the reaction is monitored. If it is, the heating element is working, if not, it needs to be replaced. In this case, it does not matter what kind of numbers the tester produces, only the presence or absence of a reaction is important. These troubleshooting methods are suitable for both storage electric water heaters and flow-through models.

To check the serviceability of the thermostat removed from the water heater, you need to set the adjustment knob to maximum and measure at the inlet and outlet of the device. If the needle of the tester remains calm, i.e. its position does not change, which means that the thermostat is faulty and needs to be replaced.

If the arrow deviates, then you need to continue testing. Now you should set the minimum position on the thermostat and attach the test leads of the tester to the contacts. It will not be easy to continue the diagnosis alone, the probes will have to be fixed or asked someone to hold them in the correct position for a while.

After that, you need to take a lighter and heat the tip of the temperature sensor. If the thermal relay is triggered, the circuit will open, and the resistance on the tester's scale will sharply go down, then the thermal relay can also be considered serviceable. If the system does not respond to heating, then this element is damaged and needs to be completely replaced.

Occasionally, the water heater can stop working due to a blown thermal fuse as a result of dangerous overheating of the device. It is enough to correctly adjust the operation of the device for it to start working as usual.

If the check showed that both the heating element and the thermostat are in good order, most likely problems have arisen with the control board. It is almost impossible to repair such an element at home.It will have to be replaced with a new one, and you will have to use the help of a specialist who will help you set up the electronic equipment. Most often, you just need to contact the service center, where the required element will be selected and installed correctly.

A tank leak is a serious problem that cannot always be corrected on your own. In some models, either the tank or the entire heater will need to be replaced. Sometimes the leak can be sealed, but care must be taken to restore the integrity of the outer casing and the thermal insulation layer. Usually such measures are insufficient and short-lived, and soon the leak will reoccur.

The water heater tank most often leaks if:

• damage to the internal tank has occurred;
• the heating element has deteriorated;
• leaky gasket.

If water flows at the place where the heating element is attached, it may not be necessary to repair the tank itself. A special gasket is installed in this place, the leak can be caused by its damage. The gasket is replaced and thus the problem is solved.

A water heater tank leak usually occurs due to neglect or untimely maintenance, which also includes the replacement of the magnesium anode. Another common problem is lack of grounding. This can also lead to the development of corrosive processes and the occurrence of leaks.

If you need to replace the gasket or heating element, it is best to first dismantle the faulty element in order to take it with you and find an exact analogue. Obtaining parts by eye can result in unnecessary costs. This replacement is relatively straightforward. But if problems arise with the tank, you will at least have to contact the service center. Immediately it is necessary to find documents for the water heater and clarify the warranty periods and service conditions.

Regardless of the nature of the breakdown, before starting repair work, you first need to turn off the power supply, remove the protective cover, disconnect the wires, pipes and drain the water. Wall-mounted models are usually removed from the brackets. The protective cover that hides the place for connecting the electrical wires and the fastening of the heating elements may have a different position depending on the model.

On horizontal type devices, such an element is usually located on the left, on vertical heaters - at the bottom, and on small models - in front. On some devices, you first need to unscrew the main mounting bolt located in the center. Sometimes this element is hidden under a decorative sticker.

After that, you need to carefully remove the thermostat, and then remove the tubes of the temperature sensor. They must be handled with great care. If the integrity of the thermosensor tube is broken, liquid filler will leak out. As a result, the water heater will simply have to be thrown away and a new device bought.

If there are stickers on the body with the serial number indicated, they must be kept, even if it interferes with the maintenance and repair of the product. This can affect the manufacturer's fulfillment of the warranty obligations, as well as facilitate the work of the service center employees.

The fact that there are problems in the operation of the device may indicate some changes in the mode of its operation. For instance:

• increasing the time for heating water to a predetermined temperature;
• the appearance of unusual sounds accompanying the operation of the device;
• the appearance of impurities in tap water, a change in its color, smell or taste.

If at least one of these signs is observed, the water heater should be cleaned immediately. To do this, you will have to perform the following operations:

1. Disconnect the device from the power supply.
2. Remove the protective cover.
3. Disconnect the contacts of the electric wires.
4. Shut off cold water supply.
5. Remove residual water from the tank using a hose.
6. Unscrew the screws that hold the heating element.
7. Remove the heating element and descale it.
8. Clean the inside of the drive from dirt and scale particles.
9. Rinse the device thoroughly.
10. Check the health of the magnesium anode.
11. If necessary, replace this element immediately.
12. Wait until the cleaned tank is completely dry.
13. Install the heating element in place.
14. Reassemble the device.
15. Check the tightness of all fasteners.
16. Connect the water heater to the power supply.
17. Check for grounding.

The heating element should be removed from the tank carefully, the bolts may be too stubborn, sometimes the heating element is difficult to remove due to too much scale layer. The heating element is cleaned by mechanical or chemical means, as is the removal of contaminants from the tank. If a large amount of scale is found inside the device, you should consider revising the operating mode of the water heater.

This phenomenon is often observed when the device has been operating at maximum power for a long time. It is recommended to set the maximum heating temperature not higher than 60 degrees in order to increase the life of the device and reduce the number of breakdowns. If the body of the heating device shocks, it is possible that the heating element is deformed and ruptured, or there is a breakdown in the control system.

A detailed video on diagnostics of the condition, maintenance and self-repair of domestic water heaters can be viewed here:

It is not so difficult to repair a water heater when it comes to replacing some of its elements. In the event of a serious breakdown, it would be wiser to contact a specialized service center. Correct use of the device and its timely maintenance will save you many problems and costs.

Malfunctions in the operation of the water heater may be associated with malfunctions in the operation of the internal heating element - heating element.

The reasons for these problems can be different, for example, the formation of limescale on the heating element. In this situation, it will be correct to install a water filter, which will limit the formation of limescale and extend the life of your equipment.

Also, the cause of the malfunction may be an incorrect calibration of the thermostat. In this situation, it is necessary to replace the thermostat.

There are a number of common causes of a heating element malfunction - it is an incorrect adjustment of the water temperature, which leads to an overconsumption of electricity, in which case it is necessary to readjust. Malfunction of the water supply system or leakage of taps, which can cause failure of the heating element of the water heater. The situation needs to be corrected by fixing the plumbing and taps. And also the cause of the heating element malfunction may be the incorrect connection and connection of the water heater. In this case, it is necessary to dismantle the system and connect the water heater according to the instructions.

The reason for the lack of hot water may be a faulty thermostat and heating element. For safety reasons, these devices cannot be repaired, it is better to replace them, while the best solution would be to replace them with original spare parts.

In our service center you can be offered spare parts and accessories for all brands of water heaters from manufacturers. We also carry out home repairs, which saves you the hassle of delivering equipment to the workshop and the costs associated with transportation, dismantling and installation after repairs.

We employ professionals with higher engineering education, and we also have all the diagnostic equipment in service. In our service center there are discounts for beneficiaries, and we also offer low prices for our services.

Our reader and author Anatoly Matveichuk continues to share home secrets. This time he tells how to repair a burned out heating element without additional costs.

The second heating element that burned out in a year in a home water heater suggested looking for the causes of frequent breakdowns.After draining the water and dismantling the electrical circuit, he unscrewed the clamping flange nuts. With difficulty, he pulled out the heating element block covered with scale. After cleaning the copper pipes of the heating coils, I found a longitudinal crack on the low power heating element. I checked the main one - it works. It was the same a year ago: a lot of scale, a torn copper pipe and a trip to the store for a new one.

The apparent root cause is hard water from the well. Installing a calcium salt softener last year did not help. The presence of a magnesium electrode also did not increase the service life.

The second reason is low-quality spirals of electric heaters. After polling neighbors and acquaintances, it turned out that replaceable heating elements from the manufacturer of the most common water heaters in our country seem to be specially made for quick breakdown, because if the factory works for 3 years, then after replacement - only 6-8 months. I assumed that placing the two coils, two temperature sensors and a magnesium electrode too close together would accelerate overheating and failure.

The third and main reason is that domestic realities are not taken into account in the design of water heaters. Let foreign manufacturers not be offended: imported water heaters are 90% unsuitable for the hard mineralized water of the Russian hinterland. Apparently, Mendeleev came up with a table of chemical elements while researching drinking water in Tobolsk.

Upon examination of the internal 30-liter tank, I found that it consists of two cylindrical tanks of 15 liters, connected by welded 20-mm pipes.

From the first tank through the heating element mounting hole, I managed to wash the scale lumps. And in the second half, everything remained the same. I had to pour in four packs of citric acid and, while stirring, wait for the complete dissolution of the accumulated stalactites. To give 1,200 rubles for a new standard heating element in the conditions of the economic crisis and falling wages did not raise a hand. Therefore, I found a free way to restore - I simply cut off the tubes of the burnt spiral and plugged the holes formed with bronze bolts with rubber gaskets.

As a result, the hot water appliance is already working. For a 30-liter storage electric titanium, 1.5 kW is sufficient. This is how the goal of the renovation was achieved with a positive economic effect.

And I also wrote a plan for preventive acid washings for myself, posted the mode of using hot water with shutdown at night and ... put a piggy bank on the supply of clean water from the city network.

1. Dismantle the heating element. The reason for the failure is visible to the naked eye: a thick layer of scale caused the cell to overheat.

2. After cleaning, it became clear that the small heating element had burned out, while the more powerful one was not damaged.

3. I had to cut off the burnt element and plug the holes left after it with bronze bolts.

4. Now there is more free space between the heating element and the temperature sensors - and scale will not accumulate between them.

5. Bronze bolts with rubber gaskets are installed as plugs in place of the heating element.

6. The heating element is ready to work again. For a 30-liter tank, its power of 1.5 kW is quite enough.

When a colleague of mine moved, someone cut the power cord from a practically new instantaneous water heater. There are suspicions that this is the work of her ex-husband. But whoever did it, plugging in the heater will no longer work. We need to fix it.

In the workshop, they asked for only 2,000 rubles for installing a new wire. But the amount seemed to my colleague too high. I took over the repair. Everything you need was found on the nearest radio market. After a thorough study of the insides of the heater, it turned out that the screws that fix the wire at the exit from the case have a tricky head. You can't unscrew them with a simple screwdriver - you need a "horned" bit. This one was found in the stall where I bought the wire. You can start repairing.

Here's what I needed for the repair.

The heater body can be opened easily, the lid is fastened with two plastic latches.

Such a piece was sticking out of the body. I must say, he was very useful to me. Having “cut off” a piece from it, I went to choose a new wire. It's very convenient when you have a sample: you definitely won't make a mistake when buying!

Before installing a new wire, it is better to photograph the wiring, for example, with a smartphone, so that you do not confuse which wire to connect to.

We unscrew the screws in the connector block to remove the old wire cut.

We unscrew the screws that fix the wire at the output.

Using an ordinary clerical knife, we strip the ends of the new wire.

We insert the stripped wires into the block and fix them by tightening the screws.

We insert a new wire and fix it at the exit.

We put the case on the wire.

To do this, unscrew and tighten three screws. We also fix the wire with a strap with two screws.

I recommend that you additionally secure the plug body to the wire. We wind some electrical tape on the wire.

Now the body has sat down with an interference - you cannot pull the wire out of the plug.

The wire is connected - you can install the heater in its place.

Before you start repairing a water heater, you should study the theoretical part of the process.Today, the most affordable, economical and efficient heating medium heater in hot water heating and hot water supply systems is an electric boiler. But, like any complex device, the boiler is susceptible to breakdowns of various kinds. How to identify and eliminate the most common malfunctions of water heaters - read below.

In order to be able to determine the breakdown of the heater and repair the boiler, it is necessary to know its structure. So, a boiler is a flow-through type water heater, which is a key element in autonomous heating and hot water supply systems. The design of the boiler is similar to the structure of gas water heaters.

So, water heaters consist of:

• External tank with fasteners, indicators and device control panel;
• Inner tank covered with two-layer titanium enamel;
• Thermal insulation layer made of polyurethane foam between the body and the inner tank;
• Thermostat and regulator for setting the desired temperature for heating water;
• Safety valve;
• Protective magnesium anode;
• Control schemes.

The main element in the design is the heating element, which heats the water. A cooler and any other water heating equipment have a similar element. At the same time, the heater in the boiler can be of both “dry” and “wet” type.

If you do not have experience in repairing water heaters, then it is better to turn to professionals

Boilers with "dry" tenom (for example, Nova NT-DD 50, Electrolux EWH 80 Formax) are distinguished by a long service life, since they do not come into direct contact with the heating medium.

Modern models of water heaters from companies such as Combustion, Termeks, Ariston are often equipped with several tubular electric heaters. This design makes it possible to implement stepwise heating control and increase the life of the boiler.

If the water heater does not turn on, turns off, makes noise when heating, starts leaking, does not heat the water well or stops heating completely, then important parts of the device have suffered during operation. To fix breakdowns with your own hands, you need to correctly identify them. Why may the boiler not turn on?

Consider the most common malfunctions of electric water heaters and the reasons for their occurrence:

1. Problems with the power supply of the device. If the indicator lamp of the boiler operation is off, you need to check the connection of the device to the network. In order to find a breakdown, you will need to inspect both the cable and the outlet for visual damage, ring the indicator and cable, measure the voltage in the outlet with a multimeter.
2. Heating element defective. Most often, the heating element fails due to the formation of scale on their surfaces (often found in boilers from Elenberg and Atlantik), switching on the boiler with a small water pressure, incorrect connection of the device. You can check the health of the heating element with a multimeter.
3. Pressure sensor malfunction. A rubber membrane is often used as such a sensor (for example, in boilers from Polaris and Atmor). During long-term operation in harsh conditions, it may deform and act incorrectly on the microprocessor. A breakdown can be identified by examining the membrane.
4. Thermal sensor malfunction. If the thermal sensor does not work, then the heating element will not be able to heat the water. You can check the temperature sensor for serviceability by measuring its resistance with a multimeter.
5. Burnout of contacts, sticking of buttons, contacts of a time relay. Finding damaged items will not be easy. Therefore, before looking for faults in the electrics, it is necessary to exclude the above breakdowns.

In addition, the water heater may not work correctly due to poor pressure in the water supply. This can be due to both the quality of the water supply in your home and the blockage of the pipeline.

Most heaters operate at pressures ranging from 0.05 to 0.6 MPa.

If the pressure in the water supply is less, then for the correct operation of the water heating devices, you will have to install a circular pump. At the same time, some modern models (for example, from the firms Oasis and Garanterm) cannot work with a pressure in the pipeline exceeding 6 bar.

If you notice that your water heater is leaking, you should immediately disconnect the device from the power supply. After that, it is necessary to conduct a thorough inspection of the device body in order to determine the location of the leak and decide what to do next.

Equipment repair will depend on the location of the leak:

1. If the boiler flows from above, then most likely its internal tank is corroded. Such a malfunction cannot be repaired: it is impossible to weld a leaked tank without damaging its inner glass enamel.
2. If the water heater leaks from the bottom, then the breakdown may be due to wear of the safety valve. Repairing the leak will involve replacing the old valve with a new one.
3. If water drips from under the tank lid, then the problem may be a heating element leak. The electric heater, in this case, will have to be changed. If water flows from under the heating element seal, then the boiler can be repaired by tightening the fasteners.

Before starting the repair of the water heater, it must be disconnected from the electrical network.

In addition, water can ooze out of the boiler due to improper water heater connections. Therefore, before disassembling the water heater and undertaking the repair of its internal components, you should check the tightness of the connections and supply lines.

Cleaning storage water heaters is one of the most important measures to maintain the operability of the device. There are two ways to clean the boiler: mechanical and chemical.

Boilers should be serviced every 6-12 months, depending on the operating conditions.

To clean the boiler, you can call a specialist, or you can clean the device at home with your own hands. The main thing is to follow the instructions clearly.

So, in order to clean the water heater yourself, you must:

1. Disconnect the device from power and water supply. It is necessary to turn off the machine and disconnect the thermostat, shut off the cold and hot water supply.
2. Drain the water. This can be done using a relief valve. But, water will drain in this way for a long time (for example, water will drain from a 100 liter boiler for about 2.5 hours). In order to drain the water faster, it will be necessary to unscrew the cold water supply hose, and remove the check valve, insert the drain hose into the hole formed, and bring it into the sink.After that, it will be enough to unscrew the hot water supply hose.
3. Remove the bottom cover from the boiler and take a photo of the wiring diagram. Disconnect the wires.
4. Unscrew the bolts from the heater block, and carefully remove the heating element. It would be better to place a basin under the tank to drain the remaining dirty water.
5. Clean the inside of the tank with a cloth.
6. Disconnect the anode and clean the heating element. Large pieces of limescale can be removed with a knife. To clean the heating element completely, it will be necessary to place it in a container with a citric acid solution (30 grams per 2 liters of water) for a day.
7. Assemble the water heater. First, you need to connect the heating element to the anode, then insert the heating element into the tank, connect the electrical wires.

The chemical method of cleaning will be simpler in execution. To do this, you will need to fill the tank with a water solution with a special composition for cleaning boilers.

If, while cleaning the copper pipes of the electric boiler, you notice cracks or breaks on the heating element (often happens with heating elements in boilers from Thermex and Isea), then the device has burned out. You can verify this by checking the resistance of the tubular electric heater with a multimeter.

If the resistance is zero or the tester is “silent” when dialing, then the heating element is broken.

Such a tubular electric heater will have to be replaced. At the same time, it will be cheaper to purchase a new heating element of Russian or Ukrainian production. So, high-quality heating elements are made by Arismash LLC (Gorlovka).

In water heaters with two heating elements (for example, Gorenje OGBS 100 ORV9), if a small electric heater fails, it can be cut off by plugging the hole with bronze bolts. But such a measure is considered temporary (a large heating element can overload and fail when heated), and is only suitable for repairing electric heaters in boilers of 30-50 liters.

After prolonged operation of the heating element of the water heater, it may need to be replaced or cleaned

Protecting the heating element from premature failure will allow:

• Timely replacement of the anode. A magnesium anode is installed in heating elements to soften water. That is, scale forms on it more than on tubular heaters. Therefore, it should be changed, on average, once every 1-1.5 years.
• Installation of filters for cleaning and softening water on the pipe at the entrance to the equipment.

In addition, the rules for operating the boiler should be observed. So, the water heater should never be turned on with an empty tank. It is not recommended to set the thermostat to maximum values. Otherwise, the heating element, as a device that maintains a given water temperature, will turn on more often and be produced faster.

To check the health of the thermostat, you need to measure its resistance using a household ohmmeter or multimeter. To do this, you will need to remove the thermometer and connect the tester to its contacts, setting the handle on the device to the maximum value.

If the tester shows zero resistance, then the thermostat is out of order.

Such a thermostat will need to be replaced with a new one. You can choose a new thermostat based on the brand of the water heater, the volume of the tank, the size and power of the heating element.

In addition, when choosing, you will need to take into account:

• The amount of current for which the thermostat is designed;
• Device functions (regulation, protection);
• Thermoregulator type (rod, capillary, electronic).

When choosing a regulator in a store, you should show the consultant a passport from the boiler. This will allow you to select the most suitable device.