How to make a do-it-yourself water heater repair: methods available for a home master

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

If you wish, you can repair the water heater with your own hands, provided that the breakdown is simple. But serious damage will have to be fixed in the service center.

In this article, we will analyze common types of breakdowns and provide recommendations for their elimination, which will allow any more or less experienced master to cope with the repair.

The principle of operation of the water heater

To minimize problems with the device, you should study its device and principles of operation. Usually in private households not flowing ones are used, but cumulative modelsthat allow you to use electricity more efficiently. Such a device consists of a heat exchanger tank, inside of which a heating element is installed - a heating element connected to the power supply.

An important part of the device is the temperature controller. This element allows you to maintain a constant temperature of the water inside the drive. Water flows through pipes into a heat exchanger. If its temperature is too low (as it usually happens), then the thermostat gives a signal and turns on the heater.

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

The device of the storage water heater is not too complicated. The most vulnerable elements of such a device are a tank, a heater, a thermal relay and a gasket

Also popular among consumers instantaneous water heaterswhich are presented on the market in a wide range. Such models are arranged somewhat differently.They do not heat a static volume of water, but a stream. They use more powerful heating elements, which begin to work when the water is turned on, and stop when it is turned off.

In order to study in more detail the work and device of a specific model, you need to carefully familiarize yourself with the accompanying technical documentation.

The heater tank is a solid stainless steel tank, 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 leakage of water from the device. One of the common causes of such damage is electrocorrosion.

Flow heaters usually break for the same reasons as storage models. Diagnosis and repair of such devices is carried out by similar methods.

To prevent it, you need to regularly, i.e. annually replace the inside of the magnesium anode. This element is designed specifically to prevent electrocorrosion. Over time, it wears out, and the owners of the storage tanks lose sight of the replacement of this important part.

As a result, the tank, which has been functioning properly for some time, suddenly begins to leak. An incorrect state of the magnesium anode can also affect the state of the heating element. Outside, the storage tank is usually enclosed in a metal or plastic housing, and it also has a heat-insulating shell that prevents heat loss.

Regular cleaning of the insides and the heater heater from dirt and scale, as well as replacing the magnesium anode will reduce the likelihood of breakdowns.

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.

Inlet pipes for cold water and outlet - for hot usually do not cause any problems if installation of storage or flow the heater is made correctly.

The electrical circuit of the device of a domestic water heater will help to properly repair it, which usually consists in replacing damaged elements

Typically, a water heater is equipped with two thermostats, one of which is designed to control the temperature of the water, and the second monitors the state of the first device.

Sometimes a third thermostat is used, which determines the working condition of the heater. In any case, a broken thermostat will have to be completely replaced. Distinguish capillary, rod and electronic types of thermostats. Their design is different, but the principle of their work is similar.

The insulating gasket not only serves to seal the connection of the elements of the water heater, it is also necessary as an electrical insulator. This element is recommended to be replaced regularly at each maintenance of the water heater.

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

Common breakdowns and repair methods

Next, we consider the most common problems with a water heater and provide repair methods for each of the breakdowns.

Problem # 1 - heater failure

Damage to the heating element is a characteristic problem for both flowing and storage water heaters. This element operates under high load 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 arose with the heater.

The heater should be removed from the tank carefully, especially if a significant amount of scale has accumulated on its surface. Sudden movements can cause deformation and damage to some elements.

First you need to check whether electricity is supplied to the heating element and the thermostat. In the places where the cable is connected, the voltage is checked by the tester.

If there is no voltage, you may need to replace the cable itself or check if the electricity is disconnected throughout the house.

Regardless of the type of model, each thermostat has a power button. When you press it, the device turns on, and when you turn it off, the button returns to its original position

If there is electricity and the cable is working, then problems arose with the heater, which will have to be replaced, or with a thermostat. To understand what exactly is broken, you need to remove the thermostat and check it with a tester.

Testing the health of the heater is as follows. First, the measuring scale of the device is set to a range 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 heater from the network and check the potential at the terminals of the heating element. The lack of response of the tester will indicate that the device is faulty. 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 uninsulated.

They put the contacts of the tester and watch the reaction. If it is, the heater is in good condition; if not, it’s necessary replace the heater. In this case, it does not matter which numbers the tester gives out; only the presence or absence of a reaction is important.

These fault detection methods are suitable for storage electric water heaters as well as for flow type models.

To determine the health of the heater and the thermal relay, an electric tester is used. Typically, the presence of voltage at the contacts indicates the serviceability of the element, and its absence indicates the need for repair

Problem # 2 - thermostat breakdown

To check the serviceability of the thermostat removed from the water heater, you need to set the adjustment knob to maximum and take a measurement at the input and output of the device. If the tester needle 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 it is necessary to set the minimum position on the thermostat and attach the test tester probes on the contacts. It will not be easy to continue the diagnosis alone, the probes will have to be fixed or ask someone to hold them in the correct position for some time.

After that, you need to take a lighter and heat the tip of the temperature sensor. If the thermal relay operates, the circuit will open, and the resistance on the tester 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.

Sometimes the water heater may stop working due to operation safety valve as a result of dangerous overheating of the device. It is enough to correctly adjust the operation of the device so that it starts to work in normal mode.

First you need to unfasten the fasteners of the heating elements and the thermostat (red arrows), then unscrew the screw (green arrow) and nuts (blue arrows. The thermostat is circled by a yellow line

Problem # 3 - control board malfunction

If the check showed that both the heater and the thermostat are working, most likely, problems arose with the control board. To repair such an element at home is almost impossible.

You will have to replace it with a new one, and you will have to use the help of a specialist who will help you set up electronic equipment. Most often, you just need to contact the service center, where the desired item will be selected and installed correctly.

Typically, the heating element is fastened with six bolts and nuts (marked with red pointers). When reassembling, it is recommended to tighten them evenly.

Problem # 4 - Tank Leak

A tank leak is a serious problem that cannot always be corrected independently. In some models, you will have to replace either the tank or the entire heater.

Sometimes the leak can be sealed, but care must be taken to restore the integrity of the outer casing and the insulation layer. Typically, such measures are insufficient and short-lived, soon a leak will occur again.

If water leaks from the places indicated by black markers, it is probably necessary to replace the gasket or heater; the red markers indicate the places of leaks when the inner tank is damaged

A water tank often leaks if:

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

If water flows at the attachment point of the heating element, it is possible that the tank itself will not need to be repaired. A special gasket is installed in this place, the leak may be caused by its damage. The gasket is replaced and thus solve the problem.

A water tank leak usually occurs due to a careless attitude or untimely maintenance, which also includes replacing the magnesium anode. Another common problem is the lack of grounding. This can also lead to the development of corrosion processes and leakage.

If it is necessary to replace the gasket, you should choose a new one of exactly the same size and shape and made of suitable materials

If you need to replace the gasket or heater, it is best to first dismantle the faulty element in order to take it with you and choose the exact analogue. Purchasing parts “by eye” can lead to unnecessary expenses. Performing such a replacement is relatively easy.

But if problems arose with the tank, you will have to at least contact a service center. Immediately you need to find the documents for the water heater and clarify the warranty periods and service conditions.

Before repairing or cleaning the water heater, it is necessary to remove the protective cover, which can be located at the bottom, center or side

Recommendations for home repairs

Regardless of the nature of the failure, before starting repairs, you must first 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 connection point of the electric 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 - on the bottom, and on small models - in front. In 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 temperature sensor tubes. They must be handled very carefully. If the integrity of the temperature sensor tube is compromised, liquid filler will leak out of them. As a result, the water heater will simply have to be thrown away and a new device purchased.

The temperature sensor tubes highlighted with a blue line should be protected from any deforming effect, if they break, you will have to completely replace the entire device

If the thermal relay of a domestic water heater becomes unusable, it will have to be completely replaced. The models of such devices are diverse, it is best to choose an analog with a similar device and characteristics

If there are stickers on the case on which the serial number is indicated, they must be saved, even if it interferes with the maintenance and repair of the product.This may affect the manufacturer’s fulfillment of warranty obligations, as well as facilitate the work of the service center employees.

Basic rules for servicing the device

For a long and trouble-free operation of the water heater, it is important to observe rules of its operation and service. Otherwise, breakdowns are inevitable.

The fact that the device has encountered problems may indicate some changes in the mode of its operation:

• 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, immediately clean the water heater.

To do this, you must perform the following operations:

1. Disconnect the device from the power supply.
2. Remove the protective cover.
3. Disconnect the wires.
4. Block the flow of cold water.
5. Using a hose, remove residual water from the tank.
6. Unscrew the bolts that hold the heating element.
7. Remove the heater and descale it.
8. Clean the inside of the drive from dirt and scale particles.
9. Flush the device thoroughly.
10. Check the integrity of the magnesium anode.
11. If necessary, replace this item immediately.
12. Wait until the cleaned tank is completely dry.
13. Replace the heater.
14. Reassemble the device.
15. Check the reliability of all fasteners.
16. Connect the water heater to the power supply.
17. Check for grounding.

The heater must be removed from the tank carefully, the bolts may be too unstable, sometimes the heating element is difficult to remove due to too much scale.

TENA is cleaned by mechanical or chemical means, as well as 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 for a long time operates at maximum power. It is recommended to set the maximum heating temperature to not higher than 60 degrees in order to increase the life of the device and reduce the number of breakdowns.

If the housing of the heater is shocking, it is possible that the heater has a deformation and rupture, or there may be a breakdown in the control system.

Conclusions and useful video on the topic

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

Repairing a water heater is not so difficult 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. Proper operation of the device and its timely maintenance will save you from many problems and costs.

You have been repairing water heaters for a long time and want to supplement our material with useful tips and professional secrets to eliminate various kinds of breakdowns? Or was it the first time you encountered a malfunction and cannot find its cause? Write your comments, ask questions, share your opinion below the article.