Boiler error codes bosch 6000 s7. Bosch gas boiler malfunctions: error codes and what to do in a specific situation

Problem: “On a new BOSCH WBN 6000-24c boiler, an EA error appears - no flame was detected. The more degrees are set, the less frequent the error. But at low temperatures, it gives an error almost every day. The flame icon disappears before the error occurs. What to do?"

Check if the protective conductor is connected;
Make sure the gas cock is open;
Check gas pressure, correct if necessary;
Make sure that the connection to the mains is working properly;
Check electrodes with wires, replace if necessary;
Check the flue gas outlet system, clean or repair if necessary;
Check the gas regulation, correct if necessary;
For natural gas: check the gas flow monitor. Replace if necessary;
When working with combustion air intake from a room, check the air supply to the room and ventilation openings;
Clean the heat exchanger;
Check gas valve, replace if necessary.

In 90% of cases, the problem is in the board. The best thing is to immediately contact the service center. There they will be able to provide high-quality assistance: make diagnostics and repair the boiler.

Hopefully the article " Gas boiler WBN BOSCH 6000-24c EA error"Was useful to you.

2017-04-29 Evgeny Fomenko

The device and principle of operation of Bosch boilers

The most popular models among the line of Bosch boilers are double-circuit. They are faced with two tasks: the first is to heat the room to a given temperature, the second is to ensure hot water for household needs.

Bosch devices, namely the Bosch Gas 4000 W and Junkers Bosch models, are equipped with two independent heat exchangers, which allows them to perfectly perform two tasks: heating water and providing heat in the room.

In each of the models, it is possible to choose the device power that suits you from 12 to 35 kW; when choosing, the area of the room is taken into account. With regard to heating liquid for household needs, the productivity is about 8-13 liters per minute.

Advantages of a wall-mounted double-circuit boiler:

The boiler can be built into the kitchen wall

Disadvantages:

The first 20-40 seconds after you turn on the hot water tap, cold water flows.

Let's take a closer look at how the device works, using the example of the Bosch Gas 4000 W ZWA 24 model. When the boiler operates in heating mode, use gas burner heat is transferred to the primary heat exchanger, which is a structure of copper tubes and records.

So that they do not deteriorate from exposure high temperatures and water, their surface is covered with a protective layer. Its main task is to transfer the heat generated during the combustion of the flame to the heating system. The movement of water in the system is provided by a pump.

Also, the design provides a three-way valve, its task is to prevent water from entering the secondary heat exchanger. A secondary heat exchanger is required to heat domestic water. The heated liquid for the heating circuit leaves the device through the heating supply line, and the cooled liquid enters through the heating return line.

When the boiler is set to heat water for consumption, the 3-way valve closes the heating circuit. The heated liquid flows from the primary heat exchanger to the secondary one, and then flows out of the device.

Bosch boiler three-way valve

The plus when using different heat exchangers is obvious. When heating is often used plain water, but it usually contains impurities. When it heats up, impurities begin to form deposits, which negatively affect the heat exchanger, reduce it throughput, prevent water from warming up, shorten its service life.

And when the liquid that flows through the primary heat exchanger, it is in a closed circuit, does not change its chemical properties, minimizes negative consequences.

The liquid that flows through the secondary heat exchanger will build up deposits over time and over time the heat exchanger will need to be replaced or cleaned. If the malfunction occurs on winter period, your boiler will be able to operate smoothly in heating mode using the primary radiator.

Major error codes

Like any device, the Bosch gas boiler also sometimes fails and needs repair, let's take a closer look at it possible malfunctions and ways to eliminate them.

11

Error 11 is possible in the Bosch BWC 42 device, it stands, in the same way as error E9, signals that the flue gas temperature limiter has been triggered.

Flue gas temperature limiter

You need to do the following:

check for subject wire damage flue gas temperature limiter, if you find rupture or melting, replace;
check pressure in the device;
check temperature limiter;
check serviceability of the pump when it starts;
if air has accumulated in the boiler, drain it.

23

Error 23 is not an error, this code appears during settings and indicates the type of natural gas used

50

Error 50 appears on Bosch ZWA 24 models when there is no flame.

Boiler Bosch ZWA 24

How to fix it:

70

Error 70 means a malfunction of the differential relay during ignition.

Reasons and ways to eliminate it:

differential relay failure, you can determine by measuring its resistance, if it does not correspond to the nominal, the relay will be replaced;
mechanical breakdown of contacts and wires suitable for the relay, check and connect the wires;
poor chimney performance, it may become clogged, clean the chimney;
incorrect setting or breakdown of the fan, adjust the operation of the fan, if it is faulty, replace it.

a2

Error a2 appears when exhaust flue gases exit on the combustion chamber, indicating that the heat exchanger is clogged with soot and fumes. To eliminate, clean the heat exchanger.

Cleaning the heat exchanger with compressed air

e2

Error e2 - the flow temperature sensor is faulty. Call the sensor for availability short circuit or an open, inspect the connecting wires for a broken circuit or oxidation. Strip or connect the wires, in case of sensor failure, replace with a new one.

e9

Error e9 means the temperature limiter has been triggered.

The reasons for the appearance and methods of elimination may be as follows:

ea

Error ea signals the absence of a flame in the on state.

When this code appears, you should check:

er

Error er (ep) appears in case of incorrect operation of the boiler in the event of malfunctions in any of the device blocks.

c3

Error c3 appears on the Bosch ZWE boiler in the event of the appearance of exhaust gases on the combustion chamber. This problem can be eliminated by cleaning the heat exchanger in accordance with the instructions in the instructions.

c4

When the differential pressure switch is closed and the fan is off, error c4 appears.

Differential relay

When this code appears, you can do the following:

blow out the pipes coming from the relay, after removing the relay, which is located in the upper part of the boiler. If the relay clicks, the problem is eliminated;
measure resistance with a multimeter for an open or short circuit, if the parameters are inappropriate, the relay must be changed.

c6

Error c6 means that the differential relay does not turn on when the fan is turned on.

What to do when this code appears:

check the chimney, eliminate interference, in coaxial chimneys sometimes it can be ice or frost.
see if there is condensation on the tubes coming from the relay. Dry the tubes with a hair dryer.
check relay for short circuit or open, replace the relay if necessary.

ce

The ce error is a fairly often repeated code in Bosch gas boilers (bosch gaz) 6000 24 kW and means insufficient pressure in the heating circuit.

Bosch boiler gas 6000 24 kW

The lack of water in the circuit is determined by the pressure gauge:

if the pressure gauge is in the red zone, it is necessary to add water to the system using the make-up tap, which is located under the device;
if the pressure gauge is in the green zone, change the pressure sensor. The sensor may have a defective microswitch or diaphragm.

f0

Error f0 means an internal fault. When it appears, you need to check the reliability of the connection of the terminals and wires to the electronic board. If the wires are not oxidized, the connections are not broken, then this is a malfunction of the board itself, it should be replaced.

fd

The fd error appears if the button has been pressed for more than 30 seconds. To reset this code, press and hold the button for less than this time.

se

The se error signals an insufficient filling of the heating system.

Heat exchanger with scale and after cleaning

What should be done:

add water:
the reason why the pressure drops can be a leak or depressurization of heating pipes. If the pipes are hot, it is difficult to detect a malfunction, as water can evaporate at the leak. To determine, cool the system, seal the joints in the places of leakage:
the heat exchanger may be clogged with scale, remove and rinse it, the procedure is described in the instructions for the boiler.

Other malfunctions

The above were the most common error codes, let's look at other possible malfunctions.

Sometimes there are such problems:

Bosch boiler errors - Meaning, causes and remedies

We have such a problem. The Bosch boiler is two-office, we use it for only six months. They turned on hot water, but it does not heat up, knocks out the boiler and shows an error E9. The filter was cleaned, the device started up, but after an hour it turned off again. Shows the error. When we start, the pressure rises immediately and the unit is cut down. Then we turn on, the fuses immediately burn out and the boiler goes out. So we can't turn it on. Please help in
what could be the reason?

Most likely your pump is jammed. Usually the fuses are lit because of the pump.

Boiler bosch gas 6000w. Was purchased in August this year. As a sudden cold snap came, it turned off and showed an error C6 (the differential pressure switch does not turn on). After removing the front cover, it was found that the tubes that fit this relay were covered with frost. After drying the tubes, the device started up. This situation has been repeated several times already. Is there any way
get rid of this problem?

It is necessary to look at how the smoke exhaust system is made. Separate system often leads to such consequences. We recommend replacing it with a coaxial one. If there is no opportunity to change the chimney, then the pipes must be insulated.

Wall mounted boiler Wbn 6000-24. The gas is natural. The EA error has been appearing for a very long time. After reading about the EA error, I decided to find out the firmware of the board and the settings of the fan stage. If the software version displays "245-03" in the menu and does not seem to raise any questions, then the menu of the fan stages shows the number "17". Horizontal chimney system with a concentric pipe. The exit from the boiler is about 2 meters. No fence adapter
I have not installed air from the inside of the room and the air enters the unit from outside the room. What guided the masters when they installed the 17th stage of the fan, although, judging by the instructions, the 2nd stage is needed. Do I need to change the board?

No adapter required. You have a standard coaxial with outdoor air intake. It helps to get rid of this error by setting the fan step to 5. I had the same thing, and when I asked 5, there was no error for a year now.

Tell me, does the burner use modulation only when using a thermostat or in some other cases?

When the temperature of the coolant approaches the set modulation, the boiler turns on in any case, regardless of whether there is a thermostat or not, but since this process takes little time, it is difficult to fix it. If an OT thermostat is used, then modulations begin to occur when the room temperature approaches the set one. If an On / Off thermostat is installed, there is no connection.

Private house 70m2 300mm foam block 50mm mineral wool and facing with ceramic bricks. There are plans to expand the area by another 50-60 sq. m. On the ground floor there is a transformer substation 33m2, heating batteries are installed on both floors. The hot water supply is implemented by a kitchen and a bathroom, and there will be a second bathroom in the one in need. I would like to supply BKN Drazice 125. Since a riser is installed in my house, I plan to install a wall gas boiler with
coaxial chimney... Considering different variants... The most optimal for the price is the Bosch 6000 (18 kW), but the bosch gaz 7000 has a minimum power of 24 kW, which, I think, is too much for me. Of the important, I require that the boiler has the ability to set the temperature in the boiler and, in the future, it would be possible to mount a room thermostat and outdoor sensor... Interested in
the difference between the specified models by the composition of components or by the place of assembly? Maybe there are some other fundamental differences?

In your case, the most optimal would be model bosch gaz wbn6000-18 and wstb 120.

Error codes for Bosch WBN 6000 boilers

Error A7- Malfunction of the DHW temperature sensor. Inspect the sensor for a defect or short circuit and its wiring. Replace if necessary.

Error Ad- The unit cannot fix the boiler temperature sensor. It is required to inspect the boiler temperature sensor and connecting wires.

Error C1- The fan rotates at a low speed. Need to check the mains voltage. Also inspect the flue gas system and, if necessary, clean or repair it.

Error C4- No opening of the differential pressure switch if the fan is off. It is required to examine the diff. pressure switch.

Error C6- Differential pressure switch does not close. Check the fan and wires with plugs. Replace if required. Inspect diff. pressure switch and flue gas outlet pipes.

Error C7- The fan does not work. Check the fan and its wires with plugs. Replace if required.

CE error- There is not enough pressure in heating system... Water is required.

Error d7- Malfunction of the gas system. Check the connecting wire. Inspect the gas system and replace if necessary.

Error E2- Malfunction of the temperature sensor in the supply line (interruption). It is required to check for possible damage or short circuit of the sensor and its wiring. Replace if required.

Error E9- The temperature limiter in the heat exchanger is triggered. It is required to check for possible damage to the temperature limiter of the heat exchanger and its connecting wires. Replace if necessary. Check the nominal system pressure. Inspect the temperature limiter and replace with a new one if necessary. Run test run circulation pump and if
it is necessary to replace it. Check fuses, replace if necessary. Remove air from the unit. Check the water circuit in the heat exchanger. Replace if necessary. Check the flue gas temperature limiter for possible damage.

EA error- No flame. Check the connection of the protection wires. See if the gas cock is open. Test the supply gas pressure reading and eliminate if necessary. Check the connection to electrical network, electrodes with wires and, if required, replace. Inspect the flue system, clean or repair. Check the gas regulation, eliminate if necessary. For natural gas: Inspect the gas flow switch. Change if necessary. When working with combustion air intake from the room, check the air flow into the room and the ventilation openings. Clean the heat exchanger. Check gas system, replace if necessary.

Error F7- When switched off, the boiler detects a flame. Check for oxidation of the electrodes, replace if necessary. Inspect the flue gas system and, if necessary, clean or repair. Check the electronic control board for moisture, dry if necessary.

FA error- A flame is detected when the gas supply is turned off. Check gas system, replace if necessary. Inspect electrodes and connecting wires, replace if necessary. Inspect the flue system, clean or repair.

Error P- The type of boiler is not detected. Set up the unit type.

Fd error

Error codes for boilers Bosch ZWC MFA

Code A2, C3- Flue gas outlet on the combustion chamber. Check the heat exchanger for clogging.

Code A3- No flue gas temperature sensor detected. The sensor and connecting cables need to be checked for damage.

A4 code- Flue gas outlet at the flow protector. Check the flue gas outlet.

Code A6- The temperature sensor in the combustion chamber is not detected. The sensor and connecting cables need to be checked for damage.

Code A7- Malfunction of the hot water temperature sensor (DHW). Perform a check to find defects or short circuits of the temperature sensor and its wiring, if necessary, replace.

Code A8- The contact with the BUS bus has been interrupted. Check the overhead cable and regulators.

Code A9- Incorrect installation of the DHW sensor. Check the installation distances, if necessary remove the sensor and reinstall it using heat-conducting paste.

AC code- The module is not defined. The module is not connected correctly. Check the module, outside temperature sensor, remote control and contacts.

Ad code- The unit cannot fix the boiler temperature sensor. It is required to inspect the boiler temperature sensor and wire contacts.

Code b1- No coding plug defined. Conduct correct installation coding plug, measure it and replace if required.

Codes C1, C6- Differential pressure switch does not close. Check the fan and wires with plugs. Replace if required. Inspect diff. pressure switch and flue gas outlet pipes.

Code C4- Dif. the pressure switch in the off position does not open. Check the differential pressure switch.

CC code- The control unit cannot detect the outside temperature sensor. It is required to inspect the sensor and contact cable for breakage.

Code d3- No jumper 161 was found at ST8. If there is a jumper, insert the plug correctly, check the external stop. Otherwise: check if a jumper is present.

D4 code- There is a large temperature difference. Check the circulation pump, bypass hose and system pressure.

D5 code- The external temperature sensor is damaged. Check the sensor and the connection contacts.

Code E2- The flow temperature sensor is defective. Check the sensor and the connection contacts.

E9 code- A limiter has been triggered in the flow line. Check the pressure in the system, temperature sensors. Check the functions of the pumps and the fuse on control board, remove air from the unit.

EA Code- No flame detected. Inspect the gas cock. Check the pressure in the gas network, the mains connection, the ignition electrode with cable and the ionization electrode with cable.

F0 code- Internal problem. Check the correct connection of the electrical plug contacts and the starting lines, if necessary replace the electronic board.

F7 code- The flame is detected when the unit is off. Check electrodes and cables. The flue gas removal system may be defective. Check control board for moisture.

FA code- Flame detection after gas supply shutdown. Inspect the ionization electrode. Check the gas system.

Fd code- Incorrect pressing of the button (duration is more than 30 seconds). Press the button again less than 30 seconds.

Malfunctions and adjustments of Bosch boilers

Bosch assures that its heat exchangers are not covered with special protective anti-corrosion paint. Heat exchangers from other companies (Viessmann, Vaillant, Ariston, Baxi) have protective layer, and they have it pure copper. And they present it as the advantages of their models. Is this so or is it just a reduction in the cost of the device.

Copper really does not corrode, which is why it is used. But due to its properties, copper burns rather quickly.

As I know there are two options BKN connections to a double-circuit gas boiler. First, through a three-way valve. Second, through a hydraulic separator. In both cases, it is used as a consumer for the heating system, respectively, it will be heated from the temperature of the heating system. This is clear to me. But I do not understand what to do with the DHW taps, and whether it is possible to simply put plugs on them. At first I
I assumed that I would buy a Bosch 6000 single-circuit boiler, but since it was not available, I was advised to opt for a double-circuit one. And I’m thinking, if I drown out the outputs, will the heat exchanger be damaged (will it burn out without water)? Since I will not keep the unit constantly operating at maximum, let the BKN continue to work. Moreover, I bought ACV Comfort 130, and by design it is a tank in the tank and, in fact, should keep the temperature better than with a coil. Among the disadvantages of such boilers is the maximum pressure of 3 bars, and safety valve on the same pressure. And knowledgeable people report that if the valve for some reason does not work, then the tank will burst. About the double-circuit model - I am afraid that if the boiler fails, I do not hot water I'll stay.

Your conclusions are correct only for purified water. For household needs, you can establish a backup line. But in my memory, the cases of failure of ACV boilers have never happened.

In a private house, I organize a separate smoke exhaust for a 24 kW Bosch 6000 gas boiler. In this regard, I have two questions. Exhaust tract. Is it worth going from "pants" 80-80 through a tee with a condensate drain to a vertical chimney diameter of 100 mm? Pipe cost different diameters does not differ much from each other. Chimney heights up to tee 4800 mm. I bring the pipe through the roof
given 10 degrees. Intake tract. I am going to organize air intake in an unheated and well-ventilated attic. Before outer wall about 4 meters. Do not take air from the room good decision... The distance from the point of intake in the attic room to the upper plane of the unit is about 1050 mm (and inside the boiler room 800 mm of the entire length). In winter, such a solution can create a number of problems,
the main one is that air with outside temperature will be supplied to the device. Education is also possible strong condensation on the duct, which will be lowered onto the body. But if condensation can be dealt with by thermal insulation, then how to solve the problem of admission warm air I do not understand. As an option, I considered it to feed the air duct from the chimney of the bath (you will need to weld
water register with a diameter of 300-500mm). Organize circulation in the register in a separate circuit. It is very difficult, but it should work. Tell me which chimney kit is suitable for installation on wbn 6000-24 c? It is necessary to bring the chimney directly behind the wall with a thickness of 375 mm; further it will not need to be pulled anywhere. Since the prices for branded equipment are very high, I would like to try another manufacturer.
Neva, for example. Will it be possible to reprogram a single-circuit unit if you disconnect the DHW flow sensor first?

No. It will be necessary to replace the control board of a single-circuit boiler and the hydraulic unit from it. And also additionally install a three-way valve.

We recently flushed the heat exchangers of a Bosch 6000 gas boiler. I worked for a month and kept the pressure at 1. Then I attracted a strange babbling sound inside it before igniting the burner (in cooling mode), as if water were being poured from one mug into another. He looked, and the pressure was 0, In theory, it should have turned off automatically when the pressure in the system dropped to 0.5, but it worked and warmed up the batteries.
The only thing that appeared is a different sound and murmur. I added the pressure to 1, but the next day the pressure dropped back to 0.5 (i.e. water is leaking somewhere). I checked pipes and radiators, but found no leaks anywhere. It also does not drip from the unit, but the pressure still drops. Tell me what could be
problem and where to look for it?

I had a similar one. In the system, the air even after the operation of the apparatus left the air, and the pressure dropped. Is the automatic air vent valve (on top of the pump) not closed? It is necessary to always be ajar. It is better to bring the pressure to 2 atm. So that the expansion tank in the boiler also takes the volume and compensates for the outgoing air. In the radiators, of course, also bleed the air with a Mayevsky tap.

The gas wall-mounted boiler Bosch 6000 24 kW often gives an EA error and is often turned on and off. That is, conditionally - set it to at least 40 degrees, literally 5 minutes and turned off, etc. Previously, I warmed it up as it should, but now the first batteries are hot, the distant ones are barely warm, they do not reach them. It operates on the return temperature, there is no room thermostat.

The EA error can be eliminated by setting the fan stage to 5. The fact that the unit shuts down quickly means that its minimum power is too high for your system. He cannot give less than 8 kW. And you apparently have 5 radiators in the system. Here he heats this water and turns off. And why he heats them up so quickly, the following malfunctions are possible: something is clogged or airy, or the first radiators need to be balanced so that the entire flow does not go only through them. Here you need to look at the radiator diagram and so on. Try to set the pump speed to maximum (value 3) and bleed air into the radiators.

Tell me who knows about: Wall-hung gas boiler WBN 6000-18C RN. What kind of production tests are performed? Are they being launched?

Everything was fine with me, I don't think it was from the factory, most likely the storage was strange.

Prompt: the wall-mounted Bosch boiler has stopped, the pressure has risen to 3 bar, it has issued an error E9r. I tried to restart it, it worked, after 10 seconds. the pressure jumped to the maximum, I stopped everything, turned it off, released the pressure. I checked the gas pressure is normal, as it was. What could it be?

If the system is new, then the expansion tank is small, if the old one, then the expansion tank is faulty, or the make-up may poison. In your case, the malfunction expansion tank the most likely. If this is so, then option 2: pump up the pressure, replace the tank.

After opening the hot water tap and igniting the burner, the Bosch boiler gives an E2 error (the flow temperature sensor is faulty). This happens in 10-15 seconds. After closing the tap, the error is removed by itself, and the boiler continues to work in heating mode. If the tap is opened again, the situation is repeated. To complete the picture: An additional circulation pump is installed in the heating circuit, before its installation
the boiler and in heating mode showed an error E2 for a couple of seconds, and then changed to E9 (the heat exchanger temperature limiter was triggered). Water supply source borehole pump(pressure at the water supply from 2x to 3x without sudden surges).

Possible reasons such: own circulation pump is faulty (if it is only used with DHW mode), the strainer is clogged. the sensor probably shouldn't be ruled out.

Boiler zwa 24. The concept has changed, a heat exchanger from zsa, a boiler sensor and a three-way valve are required. The payment, I think, is the same for them. In general, a single-circuit must be made from a double-circuit.

The manufacturer does not recommend doing such alterations. But if there is a desire, then you need to purchase a heat exchanger. Their supply tubes are the same, but the outlet tubes are different. On the 2-circuit there is a hole for recharge, but on the 1-circuit there is not. There are 2 options. Change the pipe. Figure out how to plug the hole. The control boards are the same.

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Bosch boiler - Errors and their meaning

Error codes for Bosch WBN 6000 boilers

A7- Malfunction of the DHW temperature sensor. Inspect the sensor for a defect or short circuit and its wiring. Replace if necessary.

Ad- The unit cannot fix the boiler temperature sensor. It is required to inspect the boiler temperature sensor and connecting wires.

C1- The fan rotates at a low speed. Need to check the mains voltage. Also inspect the flue gas system and, if necessary, clean or repair it.

C4- No opening of the differential pressure switch if the fan is off. It is required to examine the diff. pressure switch.

C6- Differential pressure switch does not close. Check the fan and wires with plugs. Replace if required. Inspect diff. pressure switch and flue gas outlet pipes.

C7- The fan does not work. Check the fan and its wires with plugs. Replace if required.

CE- There is not enough pressure in the heating system. Water is required.

d7- Malfunction of the gas system. Check the connecting wire. Inspect the gas system and replace if necessary.

E2- Malfunction of the temperature sensor in the supply line (interruption). It is required to check for possible damage or short circuit of the sensor and its wiring. Replace if required.

E9- The temperature limiter in the heat exchanger is triggered. It is required to check for possible damage to the temperature limiter of the heat exchanger and its connecting wires. Replace if necessary. Check the nominal system pressure. Inspect the temperature limiter and replace with a new one if necessary. Check the start of the circulation pump and, if necessary, replace it. Check fuses, replace if necessary. Remove air from the unit. Check the water circuit in the heat exchanger. Replace if necessary. Check the flue gas temperature limiter for possible damage.

EA- No flame. Check the connection of the protection wires. See if the gas cock is open. Test the supply gas pressure reading and eliminate if necessary. Check the connection to the electrical network, electrodes with wires and, if necessary, replace. Inspect the flue system, clean or repair. Check the gas regulation,
eliminate if necessary. For natural gas: Inspect the gas flow switch. Change if necessary. When working with combustion air intake from the room, check the air flow into the room and the ventilation openings. Clean the heat exchanger. Check gas system, replace if necessary.

F7- When switched off, the boiler detects a flame. Check for oxidation of the electrodes, replace if necessary. Inspect the flue gas system and, if necessary, clean or repair. Check the electronic control board for moisture, dry if necessary.

FA- A flame is detected when the gas supply is turned off. Check gas system, replace if necessary. Inspect electrodes and connecting wires, replace if necessary. Inspect the flue system, clean or repair.

P- The type of boiler is not detected. Set up the unit type.

Error codes for boilers Bosch ZWC MFA

A2, C3- Flue gas outlet on the combustion chamber. Check the heat exchanger for clogging.

A3- No flue gas temperature sensor detected. The sensor and connecting cables need to be checked for damage.

A4- Flue gas outlet at the flow protector. Check the flue gas outlet.

A6- The temperature sensor in the combustion chamber is not detected. The sensor and connecting cables need to be checked for damage.

A7- Malfunction of the hot water temperature sensor (DHW). Perform a check to find defects or short circuits of the temperature sensor and its wiring, if necessary, replace.

A8- The contact with the BUS bus has been interrupted. Check the overhead cable and regulators.

A9- Incorrect installation of the DHW sensor. Check the installation distances, if necessary remove the sensor and reinstall it using heat-conducting paste.

AC- The module is not defined. The module is not connected correctly. Check the module, outside temperature sensor, remote control and contacts.

Ad- The unit cannot fix the boiler temperature sensor. It is required to inspect the boiler temperature sensor and wire contacts.

b1- No coding plug defined. Correctly insert the coding plug, measure it and replace if required.

C1, C6- Differential pressure switch does not close. Check the fan and wires with plugs. Replace if required. Inspect diff. pressure switch and flue gas outlet pipes.

C4- Dif. the pressure switch in the off position does not open. Check the differential pressure switch.

CC- The control unit cannot detect the outside temperature sensor. It is required to inspect the sensor and contact cable for breakage.

d3- No jumper 161 was found at ST8. If there is a jumper, insert the plug correctly, check the external stop. Otherwise: check if a jumper is present.

d4- There is a large temperature difference. Check the circulation pump, bypass hose and system pressure.

d5- The external temperature sensor is damaged. Check the sensor and the connection contacts.

E2- The flow temperature sensor is defective. Check the sensor and the connection contacts.

E9- A limiter has been triggered in the flow line. Check the pressure in the system, temperature sensors. Check the functions of the pumps and the fuse on the control board, bleed the unit.

EA- No flame detected. Inspect the gas cock. Check the pressure in the gas network, the mains connection, the ignition electrode with cable and the ionization electrode with cable.

F0- Internal problem. Check the correct connection of the electrical plug contacts and the starting lines, if necessary replace the electronic board.

F7- The flame is detected when the unit is off. Check electrodes and cables. The flue gas removal system may be defective. Check control board for moisture.

FA- Flame detection after gas supply shutdown. Inspect the ionization electrode. Check the gas system.

Fd- Incorrect pressing of the button (duration is more than 30 seconds). Press the button again less than 30 seconds.

Malfunctions and adjustments of Bosch boilers

Wall mounted boiler Wbn 6000-24. The gas is natural. The EA error has been appearing for a very long time. After reading about the EA error, I decided to find out the firmware of the board and the settings of the fan stage. If the software version displays "245-03" in the menu and does not seem to raise any questions, then the menu of the fan stages shows the number "17". Horizontal chimney system with a concentric pipe. The exit from the boiler is about 2 meters. I have not installed any adapter for air intake from inside the room and the air enters the unit from outside the room. What guided the masters when they installed the 17th stage of the fan, although, judging by the instructions, the 2nd stage is needed. Do I need to change the board?

We recently flushed the heat exchangers of a Bosch 6000 gas boiler. I worked for a month and kept the pressure at 1. Then I attracted a strange babbling sound inside it before igniting the burner (in cooling mode), as if water were being poured from one mug into another. He looked, and the pressure was 0, In theory, it should have turned off automatically when the pressure in the system dropped to 0.5, but it worked and warmed up the batteries. The only thing that appeared is a different sound and murmur. I added the pressure to 1, but the next day the pressure dropped back to 0.5 (i.e. water is leaking somewhere). I checked pipes and radiators, but found no leaks anywhere. It also does not drip from the unit, but the pressure still drops. Tell me what could be
problem and where to look for it?

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