Immergas gas boiler errors: error codes and solutions

Alexey Dedyulin
Checked by a specialist: Alexey Dedyulin
Author: Oleg Zubarev
Last update: November 2019

Agree that information about a boiler malfunction can speed up the restoration of its functionality. After all, determining the cause of the breakdown is half the battle. Right? Moreover, the error code of the gas boiler Immergas is always indicated on the display and it just needs to be decrypted.

And how to do it right, we described in detail in our article. After familiarization with which the owner of the Italian boiler will be able not only to identify malfunctions, but also to assess the situation, make a decision on how to restore its performance.

Error codes for Immergas boilers

The equipment of the specified Italian brand is modern, therefore, the determination of the causes that lead to inoperability occurs automatically, with further indication on the display.

But use such information with caution, and also remember that the owner of the boiler is responsible for its safe operation, timeliness, completeness and quality of repair. And if his actions are found to be wrong, the owner of the equipment may be punished. This is stated in the Code of Administrative Offenses (Article 7.19), and in more serious cases, sanctions will be imposed in accordance with the Criminal Code.

Using Error Codes
Deciphering of error codes is traditionally indicated in each instruction attached to the boiler. But it should be remembered that the manufacturer Immergas provides fault information to specialists. That is, ordinary users can use the codes solely at their own peril and risk. Therefore, troubleshooting is best left to the master.

An important feature of this Italian manufacturer is that its models use various software. As a result, it happens that the same warning signals are indicated by several types of codes. But they can all be combined into several categories.

Problems with the ignition of the boiler

Codes Errors 01, E00, E02 indicate that the operation of the boiler is blocked, and the reason for blocking is the lack of ignition.

Lack of ignition
It is possible to restore the operation of the unit after blocking due to the lack of ignition by pressing a single button. But this should not be done in a hurry, since initially you should make sure that there is no gas smell, draft, ventilate the room and only then try to resume the operation of the boiler

Often this problem occurs after prolonged shutdown of a gas unit, for example, in the off-season, due to air accumulation in the gas supply channels.

To restore performance should:

  1. Repeat launch;
  2. If after 10 seconds the ignition has not occurred, then press the Reset button. Such an operation will automatically unlock the boiler.

As a result, the remaining air will be removed from the gas supply pipelines and the heating equipment will start.

When the fault is overheating

Codes Errors 02, 12, E12, b 19 indicates that the boiler is suspended by a signal from the thermostat due to overheating. In addition, malfunctions in the flame monitoring system can lead to the listed errors.

Boiler heat exchanger
When used, the heat exchanger channels are quickly clogged with scale, rust particles, which leads to a violation of heat transfer. Therefore, after every pair of heating seasons, it is necessary to carry out cleaning, and without waiting for a warning signal on the display

The cause of the problem can be identified by pulling up the contacts, as well as checking the integrity of the wires.

In the worst case, you have to replace the sensor itself.

Ventilation system malfunction

Signal with code 11 indicates that there is insufficient draft in the smoke exhaust system. This error code cannot be ignored. It appears on the display after the third lock of the boiler by automation due to the indicated reason, and in a row.

Bad traction
The photo shows a structural element of the smoke exhaust system, the inner channel of which is almost completely clogged with soot, which reduces the efficiency of the boiler

More precisely, after each case of gas equipment shutdown, it automatically starts. But if traction sensor again signals that the situation has not returned to normal, then the electronics immediately makes a second shutdown.

The danger of the situation is evidenced by the fact that at the same time as code 11, the display turns red.

There are two ways to fix the cause. Which include:

  • cleaning the channels of ventilation systems and smoke removal from soot, foreign objects;
  • change in the design of ventilation and smoke exhaust systems. This will have to be done if cleaning does not give the desired long-term effect.

Unlock and start the boiler, in this case, by pressing the restart button.

Pipe ice
The photo shows ice on the smoke exhaust pipe. Moreover, such formations in severe frost can grow in a matter of hours. At the same time, it is possible to return the boiler to serviceability by chipping or by melting ice

Before proceeding with any actions, it is imperative to make sure that there is traction.

Another problem in the ventilation system indicates code 03. In this case, the boiler is blocked by a command from the sensor for monitoring the removal of combustion products.

Poor combustion products
If the error code number 03 appears on the gas boiler display, this means that carbon monoxide may be present in the room. Therefore, the solution to the problem should be approached in all seriousness.


  • decrease in the efficiency of the chimney due to the accumulation on the inner surfaces of the soot channels, other combustion products. And under difficult climatic conditions, the boiler is switched off due to the occurrence of ice;
  • fan malfunctions, if provided.

In the first case, it is possible to identify a malfunction of a gas boiler Immergaz just by looking into the chimney.If it is revealed that the internal channel is completely or partially blocked by third-party objects, soot, ice, then you will need to perform cleaning.

Fan problems

The appearance of codes Errors 16, E29, b 28 / b 29, b 65 caused by a shutdown or breakdown of the fan or Hall sensor.

The cause is a malfunction of the product itself or a problem that occurs in the circuit. For example, it can be a weakening of contacts. In addition, it is recommended that you diagnose fuse F3.

If you can’t restore the functionality using any of the above methods, then you will have to diagnose the electronic module.

Error code E65 can be seen on the display when the fan loses its function. Namely, if it produces less than 900 rpm.

Boiler fan
Fans of turbocharged boilers are another weak point of any such unit. Therefore, you should always be prepared to repair or replace it.

If this fact is confirmed during the diagnosis, the fan must be replaced.

Blocking due to coolant overheating

Codes Errors 27, E18 / E19 indicate that the boiler has been blocked due to overheating. Moreover, caused by violations in the process of fluid circulation in the system.

The reasons that triggered the appearance of this warning signal include:

  • airing the heating system. To eliminate it, it is necessary to remove excess air;
  • closed position of cranes;
  • jamming or breaking circulation pump. In the first case, its impeller must be cleaned of dirt and foreign particles, which in many cases returns the product to working capacity. In the event of a breakdown, replacement is required;
  • dirty filters to be removed and inspected. If the suspicion is confirmed, the filter element should be cleaned. In such cases, the cause of contamination is often trivalent iron (rust particles), which is effectively removed by soaking in a solution of citric acid;
  • contamination of the heat exchanger channels, which during operation are covered with a layer of scale similar to that deposited on the walls of dummies (in regions where hard water). As a result, after every couple of years of using the boiler, its heat exchanger should be cleaned.

Cleaning the heat exchanger can be done mechanically, that is, using brushes, other similar devices, as well as using special equipment, chemicals.

A detailed article on cleaning a gas boiler heat exchanger can be read here.

Water supply valve
In case of errors with E18 / E19 numbers, one of the solutions to restore the boiler’s performance may be adding water to the system. This is easy to do, as all you need to do is open a special valve on the control panel

Error codes b 24, b 30 on the display indicate that the thermistors in the supply lines and in the return circuit give different values, with a difference of 10 ° C.

Eliminate this problem by cleaning the heat exchanger from scale and other deposits.

Error code b 25 indicates that the coolant temperature in the supply line rises rapidly. Typically, such a signal indicates an insufficient amount of fluid in the heating system, which is eliminated by topping up.

System Depressurization Signals

Codes errors 28, 26 indicate that an unpleasant malfunction such as a leak has occurred in the hot water circuit of the Immergas gas boiler. Moreover, with a simultaneous increase in temperature in the DHW and heating circuits.

Basin mixer
The reason for the low pressure of the coolant in the system can be any faulty mixer. Therefore, in case of error code 28, they should be addressed first of all.

To identify the problem, the first thing you should pay attention to the serviceability of the mixers.If a leak is not detected, then an inspection of the entire heating system (pipes, radiators, connections) should be performed to detect leakage.

The code mistakes 10 appears if in the boiler heating circuit pressure decreased below the set level, which is usually 0.9 bar.

Initially, it is recommended to restart the unit with a new one, and if the presence of a malfunction is confirmed, then the location of the circuit depressurization should be identified.

The specified procedure can be performed by visual inspection. In this case, remember that replacing the leaked part will be the most practical solution.

After restoring the tightness of the circuit, it must be filled with coolant.

To do this, use the so-called recharge lever. To achieve the desired result, it must be turned counterclockwise, after which water from the centralized system will be able to get into the heating circuit of the boiler.

Leaks in heating systems
A common cause of leaks is the joints between the structural elements of the heating system. This is especially true for radiators and pipes.

The filling procedure is terminated when the pressure reaches 1.3 bar, by turning the feed lever to its original position.

Unstable power supply

The code errors 37 It is a warning that there are significant voltage surges in the network, and with its decrease to critical values ​​(175-197 V).

The consequences of this problem can only be fixed by installing voltage stabilizer, and of high quality.

Other types of errors

The code errors 15 indicates an incorrect boiler configuration. In this case, it is strongly recommended that you contact a service center.

The code mistakes 20 warns of the presence of a parasitic flame. And the danger of the situation is that often it arises in the event of a gas leak.

Therefore, when identifying code 20 on the display, it is necessary to shut off the gas supply, and then open the windows for ventilation, and then make sure that there is no leak, which is detected by the specific unpleasant odor of special gas additives.

If the leak is confirmed, then immediately it is necessary to notify the gas service on duty. If there is no danger, then to eliminate the causes, contact the service center.

E04 - the most unpleasant code, which indicates that there is a malfunction, but its cause has not been identified.

Boiler display
The error code E04 for the most part indicates that the electronics did not determine the source of the problem. Therefore, it is only clear that it is serious, since in this case the automation does not even try to restart

Therefore, you can immediately call a specialist at home, since to eliminate the consequences, you may need to diagnose all the systems and components of the unit.

The code errors 08 signals a malfunction of the unlock key of the gas boiler. This problem is usually resolved by replacing a failed structural element.

The code errors 09 the display indicates that the gas boiler setting mode is activated, and its cancellation will signal that the indicated set of digits from the display disappears.

The code mistakes 31 It is rare because it indicates that the electronic board is incompatible with the model of the boiler on which it is installed. That is, this problem usually occurs after the replacement.

Electronic board
The electronic boards of modern gas boilers are designed for effective monitoring and control, but it often happens that they break themselves

Sometimes code 31 is displayed after the boiler model name is entered incorrectly during assembly. Therefore, this procedure should be repeated. If the functionality is not restored, then the board should be replaced again.

Conclusions and useful video on the topic

From the first video you can learn about how to fix the error number 02:

The following video describes how to fix error 01:

Immergas boilers are high-tech and efficient gas equipment. In addition, they are safe to operate, as evidenced by the ability to diagnose operational problems and signal them to the user by displaying the appropriate code on the screen. This helps to avoid danger, as well as quickly eliminate the breakdown.

Have you ever had to deal with breakdowns of Immergaz boilers? Please share with our readers what error you encountered in the operation of the equipment and how you managed to fix the problem. Leave your comments in the block under the article.

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