Error E4 in a gas boiler: decoding the E04 code + steps to solve the problem
Regardless of the degree of complexity and quality of assembly of technical devices, any of them can fail during operation.The cause of violations may be simple wear and tear, factory defects or incorrect operation. Let's look at what the E4 error in a gas boiler means and threatens, and look at typical ways to correct it.
In the article we present you will find tips on diagnosing a gas heater and a step-by-step description of troubleshooting methods with the indicated alphanumeric designation.
Our recommendations will help you choose the right path to restore the boiler’s functionality. You can decide whether it’s worth fixing the situation yourself or whether it’s better to call the gas workers.
The content of the article:
Violations in working with code E4
Household gas equipment requires regular inspection and close attention from owners. After all, the slightest problem can turn into a serious disaster. From irretrievably lost equipment to various degrees of poisoning and explosions with fires - all these are the consequences of seemingly insignificant breakdowns.
Manufacturers of units for servicing private heating and hot water circuits were well aware that not all owners of the equipment would be prepared to operate them at a professional level. That is why a warning system was developed that appears on boiler displays.
One thing is bad: almost all brands have their own alphanumeric designation of boiler failure. In some ways, the decryption systems have something in common, but mostly they differ. Equipment error codes with the Bosch logo, for example, are completely unacceptable for diagnosis breakdowns of Viessmann boilers or Ariston devices.
What to do in a difficult situation if your gas water heater persistently beeps, displaying error E4? It’s as easy as shelling pears to analyze all the typical malfunctions in the operation of heating equipment, most often purchased by our compatriots.
Correcting the situation in Electrolux boilers
As an example, consider Swedish-made wall-mounted models with the Elektrolux logo. More precisely, we will analyze violations in the functionality of units with the specified type of error.
The renowned supplier of high-quality and reliable equipment has developed a unified error reporting system for single-circuit devices with a closed combustion chamber (Basic S Fi), for double-circuit models with a closed (Basic Space Fi, Basic X Fi) and open (Basic Space i) combustion chamber.
Similar codes are used to notify and decipher errors on Electrolux units of the Magnum, Basic Duo, and Quantum series.
The reasons for displaying the E4 code on the electronic display in the listed models include:
- Low pressure in the heating circuit connected to the boiler.
- Lack of contact between the pressure sensor and the internal wiring of the boiler.
- Circulation pump failure.
In all of the above cases, the command to block the boiler operation was given by the pressure sensor. There are two options: either the coolant is poorly circulating through the circuit, or it itself took the readings incorrectly.Let's start looking for the cause with the most common violation - let's check the pressure in the heating circuit served by the boiler.
Restart for diagnostic purposes
If the boiler's electronic display shows a pressure of 0.5 bar, let's try restarting the boiler first. It is possible that there is no pressure sufficient for the normal movement of the coolant through the heat exchanger due to an electrical circuit failure or pump failure.
The fact that the pump or the electrical wiring connected to it deserves attention and repair/replacement will be indicated by an increase in the pressure value after a restart by at least 0.1 bar. In both cases, you should contact the gas specialists with whom contract signed for the supply of gaseous fuel and maintenance of the unit.
Finding and eliminating leaks
If the restart did not give the results stated above, we will continue the diagnosis by inspecting the heating circuit. The most common reason for an error code E04 appearing on the electronic display of a gas boiler is a drop in coolant pressure due to a simple leak.
To detect a leak, we will inspect:
- Connections of pipes with radiators and fittings. Visually examine the floor under the system, looking for drops and puddles.
- Safety valve installation area. It is built into wall-mounted Electrolux models and located in the lower part behind the circulation pump. Dripping water will indicate the presence of a leak in the area where it is located; this is from the bottom of the case closer to the rear wall.
We eliminate leaks in the external circuit using an accessible plumbing method: we tighten the connections, change the seal or pipes, if the need to replace them is ripe. With leaks in the safety valve area, everything is somewhat more complicated.
To accurately determine the cause of the pressure drop, we call a specialist from GorGaz, who must check the pressure in the expansion tank. To do this, the coolant from the system will have to be completely drained. Without it, when cooled down, the pressure in the expander should be at least 1 bar.
If everything is wrong, then:
- The culprit is either the safety valve, which will have to be replaced.
- The expansion tank membrane is damaged. It will be necessary to change it, but most often they simply install a new tank along with a new membrane. Especially if the warranty period has not yet expired.
- The spool valve of the expansion tank nipple is leaking.In such situations, the complete spool-nipple assembly is replaced in assembled form.
After all the manipulations with the expansion tank, the master is simply obliged to pump a mixture of nitrogen and air into it to working values.
All the operations described above were carried out with the heating circuit empty. Consequently, after repair, the pipeline, heating radiators and the unit itself must be refilled with coolant. The pressure in the system ready for operation should be in the range from 0.8 to 1.2 bar.
If the pressure in the circuit filled after repair is not enough for the normal functionality of the system, we supplement the volume of coolant through the make-up valve located at the base of the housing.
By the way, the volume of coolant is replenished through the make-up valve if the pressure drop occurs due to the presence of air pockets in the circuit. They need to be released using the Mayevsky crane.
Start off air release follows from the device furthest from the boiler. After releasing the air, we make makeup and slightly loosen the air vent in the boiler.
Is it due to the pressure sensor?
Let's assume that no leak is detected, the pressure readings are normal, and the display stubbornly shows E04. What now needs to be checked and changed? You should look for a fault related to the pressure sensor or its electrical connection.
In order to check the electrical circuit between the pressure sensor and the electronic board, you will need a multimeter.If the device detects a break, the connection should be restored by replacing the damaged wire.
If everything is in order with the wiring between the pressure sensor and the control board, you need to check the contacts. If they are loosened, they should be tightened; if they are oxidized or rusted, remove the coating that impedes contact with sandpaper.
Problems with the circulation pump
All of the above actions have been carried out, but the result is disappointing? What to do if your gas boiler shows error E4, despite all your efforts? What's the catch?
List of Reasons for Finding Ways gas boiler repair is already significantly limited due to the method of eliminating possible breakdowns. Now all that remains is to examine the built-in circulation pump and the electrical wiring connected to it.
After restarting the boiler, select in the settings the rotation speed of the “compass” impeller, designated III. Remember that all test and repair activities, for which you need to remove the unit casing, must be carried out by a GorGaz specialist or a similar service.
To examine the technical condition of the pump, the gas engineer must:
- Test the pump's performance using a magnetic tester.
- Check the pump “manually” if there is no magnetic device. To do this, remove the end screw from the front panel of the pump, behind which the end of the shaft with a longitudinal recess is located. A screwdriver is inserted into it and the shaft is turned.
If the shaft does not turn, you need to check the integrity of the impeller. It is possible that it was jammed by a broken blade or a cracked part. There is only one way out - replacing the entire pump.
If the circulation pump shaft rotates freely, you will have to continue the diagnostics, for this you need to:
- Inspect and test the wiring with a multimeter, check the wire itself and terminals for irregularities/disconnections/damage. They are eliminated as they are discovered.
- Check the voltage in the power supply network. If this is the problem, all questions, including boiler repair, are referred to the centralized power supply structure. To protect equipment from power surges and similar “surprises,” it is better to connect it through a voltage stabilizer with a minimum power of 0.4 kW.
- Perform a performance test of the pump itself. To verify the serviceability or malfunction of the circulation device, remove the terminal box and check the voltage on the windings of the device in phase and zero, changing the speed of rotation of the impeller.
If the resistance when rotating the impeller at the first speed is 440 Ohms, and at the second and third speeds it is 220 Ohms, you will need to repeat the procedure. If the resistance values do not meet the standards specified by the manufacturer in the technical documentation, the device must be changed.
Variations of breakdowns with code E4
Not all manufacturers of equipment for heating coolant and water in mixers adhere to the error coding and decoding system developed by Electrolux. For example, work Baxi brand heaters are blocked for a completely different reason.
When error 04 appears on the display, the operation of the boiler is interrupted due to the command given by the flame control electrode. If the sensor responsible for this process detects a flame whose size is six times smaller than the standard one, the supply of fuel to the gas burner is stopped.
The reasons for the decrease in combustion intensity include:
- Violations in the smoke removal system. If flue gases are poorly removed from the combustion chamber, the sensor will detect a change in color or a reduction in the size of the flame.
- The electrode of the ignition device is clogged. It must be regularly cleaned of carbon deposits and dust.
- Lack of contact between the sensor and the electronic board that controls its operation.
Of course, in addition to the above reasons, a failure of the control board or sensor can cause blocking of the boiler operation.
For owners of Gaslux and Neva Lux boilers, error E4 displayed on the display will indicate overheating of the heat exchanger. This can be caused by both malfunctions in the temperature sensor and a reduction in the flow of water passing through the heat exchanger.
When the speed of movement and the volume of water passing through the heat exchanger drop, you must:
- Clean the heating circuit filter. A device clogged with scale and mineral deposits significantly impedes the movement of water through a closed pipeline.
- Check the pressure in the water supply system. It is possible that these are failures in the work of public utilities.
- Install a filter on the water supply branch that supplies water to the heating apparatus.
If the above measures do not help, check the functionality of the sensor and board, and also test the electrical connections.
But the display of error 04 on the display of Navien Ace units is associated with the detection of a false flame or a short circuit in the electrical connection of the flame sensor with the control board. In 99% of cases, you end up having to replace the board.
Conclusions and useful video on the topic
Video instruction will help you clearly understand the essence of the problem and understand methods for eliminating it:
Information about deciphering a manufacturer-coded malfunction in the operation of gas equipment will help prevent negative consequences in a timely manner. All owners of units that consume gaseous fuel need to know what they mean. It’s a pity that almost all boilers do not have the same error values.
However, the reasons for the appearance of violations are almost always identical. The main thing is to understand what is connected with what and choose the appropriate diagnostic path. We have discussed a significant number of problems in this article; you can deal with most of them on your own.
