Water heater malfunctions: main causes, do-it-yourself repairs

The quality of technology and proper installation does not guarantee the absence of breakdowns. Water heater malfunctions can be fixed by hand. The main thing is to correctly determine the breakdown. In our article, you will learn how to do this without calling the wizard.

Causes of boiler failures

To understand why heaters fail, you need to understand the principle of their operation and the purpose of the main elements. No matter what type of boiler you have – accumulative or flowing, their construction is similar. Only the brand, design and capacity of the tank differ.

The device of the heater tank is quite simple. It consists of two parts: internal and external. Between them is laid a layer of thermal insulation – polyurethane foam. The body includes two branch pipes: one with a divider at the end is used for pumping cold water, the other for hot water.

Flow type devices do not have a storage tank, and the heaters have a high power.

The presence of a thermostat allows you to set the desired heating temperature.

Most boilers are equipped magnesium anodewhich protects against corrosion. The anode requires periodic replacement, then the heater and the boiler as a whole will last much longer.

Breakdowns do not just happen, there are reasons for this:

• Power surges in the network.
• Prolonged neglect of service.
• Incorrect installation or connection of the device.
• The appearance of scale and corrosion on parts.
• Late repair.

To find out the cause and pinpoint the exact location of the problem, diagnostics of parts are carried out.

How to repair a boiler with your own hands

Consider the main malfunctions and ways to eliminate them.

Leak in the heater

The most common problem with electric boilers is considered to be a leak. Occurs due to corrosion of the tank, when individual elements fail. Most often it is:

• Lack of grounding, which leads to electrical corrosion.
• Natural wear.
• Breakage of the safety valve.

What to do if the tank is leaking? Do not weld a leak on your own: this can lead to irreparable consequences!

Why You Shouldn’t Repair Your Tank:

• The outer and inner parts are inseparable.
• In modern technology, glass enamel is used, which is easily damaged and cannot be repaired.

If the warranty period has expired, it is easier to buy a new boiler. In the future, it is recommended to pay attention to the material of the tank. You also need to change the magnesium anode more often.

It happens that a leak occurs from under the flange that secures the heater. Then you need to drain all the water, remove the gasket and assess its condition. If it is damaged or worn, replace it. In order not to miscalculate with a new gasket, take the old one to the store.

No water heating

If cold water flows instead of hot water, the heater is broken. In addition to the lack of hot water, the RCD can be knocked out when the boiler is connected to the network. Problems with heating elements arise due to corrosion and scale.

Recommended periodically replace the heating element with a new one. Even if you constantly clean the scale from the element, this can damage it and expose the contacts. Then not only the RCD will close, but also the water from the tap can be shocked.

How to understand that the scale completely covered the heating element:

• Since it precipitates, a rumble can be heard during water intake.
• There is a smell of sulfur.

To make sure that the heater is broken and does not work, diagnostics will help:

• Drain the tank.
• Open the heater cover.
• Measure the voltage at the terminals of the heating element using a tester (220-250 V).
• If everything is in order, set the multimeter to resistance measurement mode.
• Disconnect the heater from the mains.
• Disconnect the heater contacts.
• Attach the multimeter probes to them.
• When broken, the indicators will tend to infinity.
• If the part is operational, 0,68-0,37 ohms will be displayed on the screen.

Additionally, make sure that there is no current leakage to the case:

• Attach one probe to the copper pipe, the other to the heating element contact.
• If there is no leak, the display will show 1.
• If there is, the tester will give values ​​with a minus sign or, conversely, too large.

The check is performed in the same way for both flow and storage models.

The heater cannot be repaired, it must be replaced. It’s important to choose the right part for your model, so it’s best to write down the part number or take it to the store with it.

The water temperature is above normal

If too hot water is supplied, the problem is in the thermostat or thermostat. An additional sign of a breakdown is the lack of heating when the thermostat does not turn on the heating element. To perform diagnostics and repairs, the thermostat must be dismantled.

Troubleshooting:

• Disconnect the boiler from the network.
• Drain all water.
• Remove the tank from the wall.
• Remove the cover (for vertical models, the cover is located at the bottom, for horizontal models – on the left, for Termex models, the panel screw is in the middle).
• The thermostat is marked in yellow in the picture. Disconnect its contacts and remove from the case.

Now you can check the part for serviceability. The easiest way:

• Press the safety button as shown in the photo:

• Heat the copper tip with a lighter.
• If OK, the button will be disabled.

Diagnostics with a multimeter is carried out as follows:

• Set the tester knob to the maximum value.
• Measure the resistance across the contacts.
• If the multimeter does not respond, the part cannot be repaired, it is better to replace it immediately.

The boiler does not turn on for a long time, often turns off

This also indicates a problem with the heater. Due to the scale, the water can heat up for a very long time, the consumption of electricity increases, as the heat removal is disturbed. To avoid breakage, change the magnesium anode in time, which purifies water from impurities.

There are such problems:

• During operation of the appliance, the surrounding equipment also heats up. This happens when the plug is designed for more power consumption than the socket, or the contact between them is broken. It is best to call an electrician to check and replace.
• Weak water pressure. It is necessary to check whether cold water is pumped normally. Inspect the mixer, perhaps the reason is in it. If everything is in order, inspect the relief valve. Clean it from dirt and scale.
• The boiler does not turn on at all. After the repair, the device did not work? You need to check the electronics and the main board. This work is best left to a specialist.

Now you are aware of the main problems of boilers. Carry out routine inspections, install water filters, clean the heater in a timely manner, then problems will not affect you.