Problems with Vaillant gas boilers: error f28, how to fix it, as well as possible malfunctions and reviews from owners

Vailant error code 75

Unlike other boilers, the vaillant self-diagnosis system checks whether the circulation pump is running.
Since the pressure sensor is capable of quantitatively recording its change, the moment the circulation pump starts, the program checks for the presence of a pressure surge of 50 mbar for 20 seconds. The circulation pump is designed to pump coolant through the system, but at the moment of start-up it briefly creates a slight excess pressure. The absence of such a jump can be regarded as a malfunction of the circulation pump, and in order to prevent further overheating of the system and improper operation of the boiler, the automation blocks operation with error F75. In fact, error F 75 can also be caused by side effects, for example, clogged sensor, air in the heating system, borderline pressure level in the circuit (low, but within the acceptable limit). If the sensor itself is faulty, status codes F73 and F74 are provided (when the voltage at the sensor is too low or too high).

The boilers are also equipped with analog pressure gauges, so for diagnostics, the sensor readings can be compared with the readings on a mechanical pressure gauge. The accuracy of a mechanical pressure gauge is about 0.2 bar.

Error interpretation

There is some confusion in the Vaillant manufacturer's instructions and its interpretation. Regarding error f75, it is said that its causes may be a faulty pressure sensor or circulation pump. At the same time, the same table shows codes f73 and f74. The first indicates a problem in the signal circuit of the flow switch (short circuit, broken wire, poor contact), the second indicates a breakdown of the sensor itself.

The peculiarity of the Vaillant electronic circuit is that it not only controls the operation of the pump, but also the moment it reaches mode. This is how German units differ from boilers of other brands. If within 20 seconds after start-up there is no pressure jump in the system by 50 bar (that is, normal fluid circulation), the automation regards this as a malfunction of the pumping device and issues an error f75, which blocks the Vaillant boiler.

First steps

Gas boiler Vailant: operating instructions

At the same time, double-circuit boilers do not operate in heating and water heating modes. By default they work for heating. But when the hot water tap opens, the boiler switches to heating mode. It is worth knowing that water is heated in limited quantities - for domestic needs. The boiler switches to heating mode automatically after the hot water tap is closed.

Experts strongly do not recommend installing a double-circuit wall-mounted gas boiler Vailant yourself. Errors in installation will lead to the fact that it will not meet your expectations. Most of the complaints made by users are based on improper operation and errors during installation. Problems can occur due to poor quality of gas and energy supply, which is not uncommon in our country.

Boiler Vailant error f75

Vaillant Group is an international concern producing climate control equipment, with its head office in Germany. The company has been operating since 1874 and has representative offices in 60 countries, including Russia.

Vailant products are energy efficient and environmentally friendly. The consumer is offered a wide range of high-quality and reliable installations for heating and water treatment. In addition to traditional heating equipment, the company's engineers are developing solutions for using solar energy and heat in household appliances.

Causes of error f75 Vaillant

Bypass valve

Its task is to protect the circulation pump mechanism from powerful hydraulic shocks. The valve has a spring, and in case of contamination it does not completely close the channel (half-open position). When the pump starts operating, the relay does not respond to a surge in pressure, which leads to error f75 Vaillant. There may also be deposits in the bypass itself: check, rinse.

Expansion tank

Few people associate the correct operation of this device with error f75. But if the special tank is periodically not properly maintained, the pressure in the air chamber is below normal, it becomes one of the reasons for the appearance of such a fault code.

Rubber rubber gradually loses its elasticity, and deposits deposited from the system accumulate in the container body. The direct connection of the expansion tank with the hydraulic circuit of the boiler leads to the fact that part of the dirt gets into the Vaillant, to the pump.

Advice

When servicing, the tank must be dismantled after draining the coolant from the system. If the membrane is replaceable, its suitability for further use is assessed and a decision is made. The vessel itself is thoroughly washed, air (or nitrogen) is pumped into it (after installing the flask), and only then the device is connected to the heating system.

Strainer

Vaillant boilers have a miniature cleaning element installed in front of the pressure sensor to protect its cavity from sediment. During maintenance, it must be changed annually, like any consumable. Gradual contamination of the mesh leads to the fact that the sensor does not respond to changes in pressure in the pipe, and the automation periodically issues error f75.

Pump

To accurately diagnose the condition, it should be removed from the Vaillant boiler. Error f75 indicates no shaft rotation or low speed. The result is the same - there is no coolant circulation or it is weak, and the sensor does not detect this. Testing the pump is quite simple.

Electrical part

Since error f75 is caused by a small surge in pressure, it means that the operating Vaillant boiler pump does not create the required pressure. There are few reasons.

Salt deposits are removed by cleaning and washing. The damaged impeller is replaced. In service workshops, the functionality of the Vaillant boiler pump can be restored: they always have used products, and it is not difficult to find a replacement for any part. But it’s better to buy a new pump: it’s inexpensive.

Coolant

Many property owners, especially suburban ones, use antifreeze in heating systems. The special liquid loses its original properties over time - in professional slang it is called “rubber”. When the Vaillant boiler is started, the pump pumps the medium, which contains foam. As a result, voids (haverns) and the flow switch simply do not respond to changes in pressure. Hence the f75 error.

What is recommended

Practical recommendations

It is advisable to order and install a new German sensor of a new modification in the Vaillant boiler (article 0020023721). The price is quite high (around 11,500 rubles), but the warranty on it is 5 years, and the problem with the appearance of error f75 due to the “whims” of the flow switch will be solved forever. It is made in such a way that debris is excluded: special membrane material, polymer filling of voids in the sensor body.

If you have experience and methods on how to fix error f75 of a Vaillant boiler or what needs to be done based on your experience, write in the comments to this article, we will try to consider your option and analyze it in detail in this article or one of the following articles. You can also send photos and videos with comments and descriptions.

Source

Nuances of installation and operation

The installation of boiler equipment is carried out by gas company specialists in accordance with the instructions for the specific model.

Installation features of Vaiilant boilers:

The product has two levels of control: user and specialist. The first displays basic information and makes it possible to configure basic system parameters using keys and controls. The second is used for repair and maintenance and is protected by a special code.

Possible faults

Chimney

Error f33 is often encountered by property owners who do not adhere to the manufacturer’s recommendations for arranging the exhaust duct. Violations of the instructions have a negative impact on traction.

Causes

Advice

It is pointless to check the hood with the flame of a match, lighter, or candle. If there is a “wick” deviation, this does not mean that the draft for the Vailant boiler is sufficient. The sensor is characterized by a response threshold. Such recommendations from “experts” lead to erroneous conclusions and increase the time spent searching for the cause of the appearance of code 33. After removing the first elbow, it is easy to assess the condition of the pipe through inspection.

Fan

Its activation is indicated by the characteristic noise and rotation of the impeller. Error f33 appears even when the smoke exhauster is running, if it does not go into operation. When performing visual diagnostics, you need to make sure that the speed is normal. The slow rotation of the shaft is reflected in the traction - it drops, and the 33rd fault code is displayed.

Boiler fan vaillant

Differential relay

The device is triggered by the presence of draft, determined in the Vaillant boiler using the Pico device. This is where you need to look for the defect leading to error f33.

Pressure switch, impulse tube, Viessman boiler fan

Causes

Clean the Protherm boiler tubes

Venturi tube

Advice

In some cases, it will be possible to restore functionality. But this measure is temporary until a new device is purchased. If the sensor failure is associated with loss of rubber rubber elasticity due to the adhesion of tiny particles to the membrane, knock the housing on a hard surface. The sludge will fall off and the f33 error problem will be resolved.

Share your experience

If you have experience in correcting error F33 in a Vaillant gas boiler, write in the comments to this article, we will try to consider your option and analyze it in detail in this or one of the following articles. You can also send photos and videos with comments and descriptions.

Vaillant boiler error f75 and elimination methods

In this article we will look at the Vaillant TEC series boiler.
These are modern boilers of the premium segment of the famous German brand. The model range is represented by boilers with a power from 20 to 36 kW, single-circuit and combined. Depending on the configuration, the TEC series is available in two modifications: Plus and Pro. Vaillant Pro is a cheaper model, Vaillant Plus has a hot start function in hot water preparation mode, a larger secondary heat exchanger, a larger expansion tank (10 liters), a more informative LCD display and a circulation pump with automatic speed control.

The operation of any gas boiler is permissible only if there is a working fluid in the system - coolant. By the way, Vaillant prohibits the use of antifreeze or corrosion inhibitors. Therefore, prepared water should be used as a coolant.

The presence of the required filling level of the heating system is monitored by a pressure sensor. Vaillant is a fairly technologically advanced boiler, therefore, it uses a pressure sensor that has the ability to measure its digital value. In many other boilers, the pressure in the system is controlled by pressure switches based on microswitches and a conventional mechanical pressure gauge.

The principle of operation of the Vaillant sensor is as follows: in the housing there is a spring-loaded magnet and a Hall sensor. Through the membrane, the coolant pressure in the pipeline acts on the spring and moves the magnet, thereby changing its position relative to the Hall sensor. Depending on the degree of displacement, the voltage value changes on the contacts, which are fixed by the control board and displays a numerical value on the screen to the user, and also controls the permissible value.

That is, the actual pressure value in the system is constantly monitored by the control unit.

The normal pressure in Vaillant TEC series boilers is considered to be in the range from 0.7 to 2.8 bar. When filling the system, it is recommended to ensure a value of at least 1 bar.

If the pressure value recorded by the sensor differs from the normal range, this is considered a malfunction and the diagnostic system will generate an error.

Error f 75 in a Vaillant gas boiler - How to fix error f75 in a Vaillant gas boiler (Vailant)

alexxlab05.12.2017
: 0

Vaillant gas heating systems are available in various versions. The most popular are wall-mounted double-circuit boilers Vailant VUW of three series: Turbo FIT, TEC Plus and Pro.

• Vaillant ecoTECplus control panel
• Vaillant ecoTECpro control panel
• Vaillant turboFIT control panel

An analysis of the error tables in their instructions shows the identity of the problems that arise, and for the last two models the instructions are common. The article will help you understand the reasons for incorrect operation or stopping of equipment due to an emergency signal and give recommendations for eliminating them.

Vaillant boiler error f75

Unlike other boilers, the vaillant self-diagnosis system checks whether the circulation pump is running. Since the pressure sensor is capable of quantitatively recording its change, the moment the circulation pump starts, the program checks for the presence of a pressure surge of 50 mbar for 20 seconds. The circulation pump is designed to pump coolant through the system, but at the moment of start-up it briefly creates a slight excess pressure. The absence of such a jump can be regarded as a malfunction of the circulation pump, and in order to prevent further overheating of the system and improper operation of the boiler, the automation blocks operation with error F75.

In fact, error F 75 can also be caused by side effects, for example, clogged sensor, air in the heating system, borderline pressure level in the circuit (low, but within the acceptable limit). If the sensor itself is faulty, status codes F73 and F74 are provided (when the voltage at the sensor is too low or too high).

The boilers are also equipped with analog pressure gauges, so for diagnostics, the sensor readings can be compared with the readings on a mechanical pressure gauge. The accuracy of a mechanical pressure gauge is about 0.2 bar.

Basic error codes (f28, f75) and their brief explanation

There are a lot of codes for various errors or malfunctions.

Let's look at the most common ones:

IMPORTANT!

In addition to error codes marked with the letter F, there are status codes marked with the letter S. They inform about the ongoing process and are not errors.

Error f75 vaillant solutions

Since the causes of the malfunction may be insufficient pressure in the system or air, the system should be energized and the deaeration program should be started (control program P.0).

The error is reset with the “Reset” reset button (crossed out flame), or by turning the boiler off and on.

Another reason could be the expansion tank; if it is connected to the supply line, the membrane can dampen vibrations. Also, to eliminate its influence, it should be serviced - check the pressure of the air chamber of the expansion tank and, if necessary, pump it up. Maintenance of the expansion tank must be carried out after draining the water from the boiler.

If simple steps do not help, you will most likely have to remove and inspect the circulation pump. If during the inspection there is significant wear, scale deposits and dirt, it will most likely have to be replaced.

Another reason may be an automatic bypass (a device that serves to protect the pump in the event of an increase in the hydraulic resistance of the heating system). It has a spring-loaded valve, which in case of sticking (dirt or scale gets in) remains in the slightly open position.

Perhaps we have considered all the possible causes of error F75 and options for eliminating it. Other non-standard cases must be considered primarily in the context of the prerequisites for their occurrence. What a circulation pump is, how its maintenance and repair is carried out can be seen in the video below.

Source

Malfunctions and how to fix them

The appearance of one or another error on the display does not mean that serious problems have arisen. Electronics sometimes perceive sensor readings as signals about the failure or breakdown of a particular component. Therefore, usually the first action is to reset the error and restart the boiler.

If the error appears repeatedly several times in a row, there is no longer any doubt about the malfunction.

Let's look at ways to solve the most common problems:

F 22

The lack of water may indicate that the pump has stopped (check the contacts or condition of the wire, replace the pump), problems with the feed tap or with the sensor itself.

F 28

Ignition blockage occurs due to the lack of a positive result when the device attempts to ignite the gas on the burner. The most likely reason is failure of gas fittings, lack of gas in the pipeline, air entering the gas pipeline and other problems with the gas supply system.

F 29

The reason for the cessation of gas combustion is most often the cessation of supply from the gas pipeline, the recirculation of exhaust gases, which reduce the ability of the gas to ignite, or the failure of the ignition transformer. Alternatively, you should check the condition of the ground electrode.

F 36

This error occurs only on boilers with an atmospheric burner and indicates that exhaust gases have entered the living room atmosphere. The predominant reasons are poor condition of the chimney, lack of draft (reverse draft due to external conditions), too short chimney pipe . Often the reasons are too high a room temperature or a small distance from the walls made during installation of the unit.

F 75

After 5 attempts, the pressure in the system does not rise. The cause may be either the presence of air in the pipelines or pump failure . Alternatively, the expansion tank may be mistakenly connected to the supply pipeline or the overall water pressure in the main line may be weak.

Error interpretation

There is some confusion in the Vaillant manufacturer's instructions and its interpretation. Regarding error F75, it is said that its causes may be a faulty pressure sensor or circulation pump. At the same time, codes F73 and F74 are indicated in the same table. The first indicates a problem in the signal circuit of the flow switch (short circuit, broken wire, poor contact), the second indicates a breakdown of the sensor itself.

The peculiarity of the electronic circuit of Vaillant and Protherm is that it not only controls the operation of the pump, but also the moment it reaches the operating mode. This is how German units differ from boilers of other brands. If within 20 seconds after start-up there is no pressure jump in the system by 50 bar (that is, normal fluid circulation), the automation regards this as a malfunction of the pumping device and issues an error F75, which blocks the Vaillant boiler.

First steps

Reset.

This is done with a button on the Vaillant boiler panel or by turning off/on the power. Error F75 caused by power surge disappears.

Heating circuit recharge.

When the pressure in the system is below a critical value, fault code F22 is displayed. But if the coolant level is “on the verge” (minimum permissible), there will not be a difference of 50 bar when the pump starts working. Consequently, error F75 will appear.

Bleeding air.

When bubbles accumulate in the coolant, the channel is not blocked, but the circulation speed decreases. This affects the correct operation of the flow switch, which issues a corresponding signal to the electronic board. And now it generates error F75 and stops the Vaillant boiler. Models of the TEC series are equipped with a special deaeration program (P.0): after its start, the fault code disappears.

Reasons causing error F75 Vaillant

Bypass valve.

Its task is to protect the circulation pump mechanism from powerful hydraulic shocks. The valve has a spring, and in case of contamination it does not completely close the channel (half-open position). When the pump starts operating, the relay does not respond to a surge in pressure, which leads to error F75 Vaillant. There may also be deposits in the bypass itself: check, rinse.

Expansion tank.

Few people associate the correct operation of this device with error F75. But if the special tank is periodically not properly maintained, the pressure in the air chamber is below normal, it becomes one of the reasons for the appearance of such a fault code. Rubber rubber gradually loses its elasticity, and deposits deposited from the system accumulate in the container body. The direct connection of the expansion tank with the hydraulic circuit of the boiler leads to the fact that part of the dirt gets into the Vaillant, to the pump.

Advice When servicing, the tank must be removed after draining the coolant from the system. If the membrane is replaceable, its suitability for further use is assessed and a decision is made. The vessel itself is thoroughly washed, air (or nitrogen) is pumped into it (after installing the flask), and only then the device is connected to the heating system.

Pump

To accurately diagnose the condition, it should be removed from the Vaillant boiler. Error F75 indicates no shaft rotation or low speed. The result is the same - there is no coolant circulation or it is weak, and the sensor does not detect this. Testing the pump is quite simple.

Electrical part of Vaillant and Protherm pumps

Presence of voltage at the terminals. If it is not there, you need to assess the condition of the lamellas and wires: breaks, oxidation, short circuits. • Under the cover there is a 2 or 2.6 uF capacitor (check the value according to the inscription on the case). It provides the starting current. “Breakdown” or loss of capacity is one of the causes of error F75 Vaillant (the boiler pump will not start). A characteristic hum will be heard (when voltage is applied to the motor), but the shaft will remain in a static position. • There is a problem with the winding. To determine integrity, you need to measure its resistance: the norm is 275 Ohms. The ∞ symbol on the multimeter display indicates a break, when the nominal value deviates downward (R Recent

Source

Vaillant F75 boiler error

Vaillant F75 boiler error

The most annoying failure among Vaillant boilers is a violation of the coolant circulation in the device, the boiler stops and we see the F75 symbol on the display screen. If you pick up the instructions for the boiler, you can find in one of the tables that this is error F75 and a brief description of what can fail and a list of faults.

The most common reason, which is also the main one, is clogging of the rubber membrane of the sensor with products of destruction of the heating system. Why does this happen and why, after installing a new sensor, does the problem close for a short period of time and start all over again? Everything is very simple, if you disassemble the old sensor and look at its design, you can see that there is a magnet inside the sensor, which is functionally necessary to change the magnetic field when the pump is turned on, the pump turns on, a small pressure surge occurs which is transmitted to the rubber membrane of the sensor, then oscillation is transmitted to the rod with a magnet, the magnetic field changes and a signal is sent to the main board, the boiler starts working. Everything is great, of course, but only for an ideal heating system without ferrous metal pipes and without steel panel radiators, which collapse over time and small particles circulate through the system and stick precisely in the pressure sensor, given the fact that it has a magnet. Thus, the sensor membrane, due to the magnet located behind it, perfectly attracts all the sludge and loses its ability to transmit any pressure surges.

So what's now? How to solve a problem? Shouldn't you constantly change sensors? The Vaillant company, of course, has already taken care of this and released a new fifth-generation boiler, while changing the firmware of the board; on the latest versions of wall-mounted boilers, error F75 does not exist by definition, the board no longer requests to turn on the pump, but what should those people who purchased a third one do? version of the boiler, and it was sold on the market for more than ten years. There is also a solution; a service kit has been released to eliminate this error with article number 0020023721, but it is only suitable for condensing boilers. At one time, the same kit was produced for conventional wall-mounted boilers, but was discontinued, kit article number 0020023722.

In this case there is only one solution , install the sensor from the Viessmann boiler with article number 7826025, its estimated cost is about 3,700 rubles, and forget the problem like a bad dream!

Source

Typical errors

Knowing the error codes of the Vailant boiler, you can diagnose almost any malfunction. And having experience in repairing heating equipment, nothing prevents you from dealing with the breakdown yourself. The codes are displayed on digital indicators, representing two-digit numbers with the letter F. Let's look at them in more detail.

Error F28

A fairly common error that occurs when the ignition unit cannot be started. As a result, the equipment cannot start working. Error F28 in Vailant boilers can indicate either a breakdown of the system board or a malfunction of other components - the high-voltage ignition transformer, gas magnet, gas valve, ignition sensor and much more. It appears when the conductors break or there is insufficient pressure in the line. Its appearance is often caused by a simply closed gas valve.

To fix error F28, follow these steps:

If all nodes are intact, there is a high probability of an error directly on the system board. In this case, you need to contact Vailant service for its repair or complete replacement.

Error F75 may also indicate problems with the on-board water pressure sensor - it cannot recognize an increase in pressure after the pump starts.

Error F75

Another common sign of breakdown. Error F75 in Vailant boilers indicates problems with pressure in the heating system. It occurs after starting the circulation pump . Usually in this case the pressure rises by about 0.2-0.4 atmospheres. If this does not happen, the problem may lie in improper installation of the system. First, you need to check the functionality and correct connection of the expansion tank (expansomat), and then de-air the circuit.

After this, we check the functionality of the pump - it should drive the coolant along the circuit. A faulty pump must be replaced; they are usually not repaired.

Errors F0, F1, F2, F3 and F4

The first two occur in Vailant heating boilers if the coolant temperature sensor (NTC sensor) fails. It must be replaced with a sensor of a similar model. Despite the absence of vibrations, the connecting conductors may also fail - check their integrity with a multimeter. You should also evaluate the quality of the connections, inspect the connecting plugs - codes often appear due to oxidation of the contacts. Codes F2, F3 and F4 are caused by the accumulator sensor.

Errors F5 and F6 (and F15 and F16)

This code is typical for Vailant Atmo series boilers with atmospheric burners. It indicates a breakdown of the traction sensor or a break in the connecting wires. We recommend checking the integrity of the conductors and testing the sensor itself. If a breakdown occurs after disassembling and reassembling the equipment, we check that all connections are correct. In turbocharged units, codes F15 and F16 occur.

Codes F10 and F11

Their appearance means a short circuit in the supply and return temperature sensor circuits. Not only the wires need to be checked, but also the temperature sensors themselves. We test detachable connections in the same way.

Errors F13 and F14

If one of these codes appears on the digital indicator, it means that the coolant has overheated - it has heated up to a temperature of +130 degrees. For Vailant boilers, this value is critical, so the equipment is immediately turned off. If the water in the circuit is clearly cooler, there is a short circuit in the sensor itself or in the connecting wires.

Code F20

Indicates problems with the supply temperature sensor. It needs to be checked, all connections are checked in the same way. In some cases, the code indicates overheating of the coolant.

If error F22 occurs, you need to test all circuits responsible for the operation of the circulation pump and the coolant pressure sensor in the circuit.

Codes F22, F23 and F24

Error F22 is common, indicating a variety of malfunctions. It appears when there is no water in the heating circuit. Water can leak out through the smallest cracks and cracks, and problems with the pressure switch and circulation pump are also possible. In rare cases, the motherboard is to blame.

F23 at the first start indicates a problem with the coolant - there is not enough of it or the installer managed to confuse the supply and return pipes. In other cases, the culprit is the circulation pump, which requires checking and replacement. Code F24 indicates that the coolant temperature in the supply pipe is too high - we check the pump, temperature sensors and circuits. Last of all, we sin on the payment.

Error F25

In Vailant boilers, it indicates that the temperature of the combustion products in the chimney is too high. When overheating is detected, the equipment turns off. If the gas equipment and heat exchanger are working properly, we test the sensors and electrical connections.

Code F27

Some errors in Vaillant boilers indicate several possible malfunctions at once:

In the latter case, turn off the equipment, wait a few minutes, and restart.

Error F29 may appear if the ignition system is malfunctioning - check all its components.

Error F29

It is widespread and appears when there is a simple drop in pressure in the gas line and when the gas supply is completely stopped. As a result, the flame disappears, the equipment turns off, and the above code appears on the display.

Error F32

Characteristic exclusively for Vailant condensing boilers. Diagnoses a malfunction of the fan responsible for removing combustion products. In this case, check the fan and connecting wires. Sometimes the culprit is the electronic board that controls the equipment.

Errors F35 and F36

When these codes appear, open the windows and ventilate the room, check for any foreign odors. It is quite possible that combustion products go directly into the room instead of the chimney. Codes are also displayed on the display if the flow of fresh air is disrupted. The situation is typical exclusively for Vailant atmospheric boilers.

Code F61

Serious error related to the operation of the gas valves. Indicates their malfunction and the breakdown of the electronic board. In rare cases, the code is displayed when the connecting wires are broken.

Code F62

The boiler “sees” the flame for longer than four seconds after closing the gas valve. Possible reasons:

Please pay special attention to this error.

Common mistakes of Vailant gas heating boilers

Gas autonomous heating systems are the most common and optimal from an ergonomic point of view today. But due to not the best operating conditions, they are often subject to various breakdowns, regardless of the country of origin and the price of the unit.

For example, a Vaillant boiler, the malfunctions of which are often associated with poor gas purification, may not last even one season, although it costs a lot of money. And this is not the fault of the manufacturers, because the equipment is designed for optimal conditions and cannot always effectively deal with problems arising due to the fault of public utilities.

Features of operation

Particular attention should be paid to the gas burner, since it is the one that clogs most often, which leads to the inability to fully control the flame level. Carbon deposits must be removed from the internal surfaces of the working chambers. When using gas, there will be little of it, so the user will not experience any particular difficulties. It is very important to maintain the chimney so that it fully copes with its functions.

Malfunctions of the Vailant double-circuit gas boiler differ from the single-circuit model due to its more complex design. The device simultaneously acts in two capacities, so it has a double load. Let's face it, if the boiler operates only during the heating season, then the water heater has to work all year round without breaks. But it is still necessary to allocate one day during which the system will be turned off and receive appropriate service.

It is better to do this in a timely manner and save yourself from problems that may occur at the most inopportune moment. The most common problem with this category of heating equipment is water leakage at the joints. Therefore, you need to pay special attention to sealing and use the most modern means for this. The connection must be reliable in order to serve for many years and not create any problems for the owners.

Common Mistakes

It is also a fairly common problem when exhaust gases are not completely released into the atmosphere. A smoke exhauster can be of great help here, as it can even correct a not entirely correct chimney installation. The gas burner also needs to be cleaned at least once a year, and more often on the water heating circuit. To resolve more serious issues, it is better to contact the service center.

Every modern boiler is equipped with an automatic system that monitors the status of all systems and, in the event of emergency situations, quickly stops gas leaks. Therefore, there is no need to worry that an explosive concentration may occur if the boiler breaks down when no one is home.

However, it is also worth considering that the computerized control unit operates on electricity, so it is necessary to ensure an uninterrupted supply of voltage to it so that all systems continue to function as normal. For this purpose, UPSs with different battery capacities are used. It would not be superfluous to install a voltage stabilizer.

Decoding the main error codes

• 1. Error f20 on a Vaillant boiler is quite rare and indicates overheating of the equipment. This may be a consequence of the heat exchanger being clogged with various debris, as a result of which the coolant is not able to circulate fully and is heated to a critical temperature.
• 2. Error f22 is much more common. It means insufficient water in the system or its complete absence.
• 3. Error f28 of the Vaillant boiler - the electronic board burned out. This can happen as a result of a sudden voltage surge, which is why a stabilizer is needed.
• 4. Error f29 of the Vaillant gas boiler - the gas burner does not light up. After three unsuccessful ignition attempts, the boiler automatically turns off. There can be quite a few reasons, from insufficient gas pressure to a stuck valve or clogging of the holes with various debris. You will have to carry out diagnostics yourself, since automation only gives a general idea of ​​the problem.
• 5. Vaillant boiler error f36 - release of gaseous combustion products into the room. It may occur as a result of a leak in the pipeline or insufficient draft in the chimney. The solution is described above.
• 6. Error f75 on the Vaillant boiler means a lack of water pressure in the pipeline. The solution method is described a few paragraphs above.

A list of other errors with decoding can be read in the instructions that come with each model.

Source: https://promplace.ru/kotly-otopleniya/kotel-vailant-neispravnosti-1929.htm