The flame in the Bosch gas water heater does not ignite: finding the cause of the malfunction and recommendations for repair

The problem of lack of hot water is relevant not only in remote villages and towns, suburban private sector houses, but also in apartments of multi-apartment buildings. This is why water heaters remain in demand and are in demand.

However, like all technical equipment, in geysers, after a certain period of use, malfunctions appear that interfere with normal functioning. One of the most common problems is that the flame in the gas water heater does not ignite. Bosch. In our article we will look at the reasons that cause this problem in various types of geysers and how to eliminate them.

Features of ignition of geysers Bosch

A flow-through gas water heater, commonly known as a “gas water heater,” is a technical device in which water is heated using the energy released during the combustion of household gas.

Different models of brand water heaters, differing in functionality and design, also have different types of ignition. Therefore, the reasons causing problems with flame ignition may differ. But in order to diagnose them, it is first advisable to familiarize yourself in general terms with speaker device.

The basic diagram of a gas water heater, used for all models produced by Bosch. The main difference between the models is the type of ignition and the location of the modulation control knob

Gas water heaters Bosch, despite many modifications differing in the type of ignition and performance, corresponds to the general assembly scheme and consists of the following elements:

• gas fittings — a curved metal tube through which gas flows and gas supply control elements;
• gas wick — device for igniting a flame;
• burner — the place where the gas combustion process occurs;
• heat exchanger — a special tank through which a tube with running water passes; this is the place where water is heated;
• combustion gas temperature sensors — a necessary element for monitoring the proper operation of the column;
• button piezo ignition — necessary to run the column;
• speaker modulation knob — used to increase gas supply power;
• removal of combustion products.

Columns of different series may differ in the type of ignition, set of sensors and other design elements. Next, we will get acquainted with the main ones, which are important in the case of self-diagnosis of a malfunction.

Series Therm 2000 O

Affordable version. Average performance: 10 liters of hot water heats up to the required temperature in 1 minute. The device of this series is equipped automatic ignition, which runs on batteries.

The design also includes sensors for gas supply control, flame control, and traction control.

The Therm 2000 O model has mechanical control and heating temperature limitation.Using the modulation knobs on the front panel, you can manually adjust the required gas supply force

Series Therm 4000 O

Models of this series are available in 2 versions: with automatic ignition from batteries and piezo ignition. They vary in power and can heat from 10 to 15 liters of water per minute.

Geysers of this model have a number of advantages:

• uniform regulation of column modulation, which allows you to maintain the set water temperature;
• heats water even at low flow pressure (sufficient pressure is 0.1 atm).

To distinguish the ignition option, the letters are used in the designation of these gas water heaters B – columns with automatic ignition, and P – speakers with piezo ignition.

The gas supply power regulator in the Therm 4000 O series dispenser allows you to more accurately set the water temperature. They are also equipped with the highest quality heat exchangers made of copper. Their serviceability has been increased to 15 years

Series Therm 4000 S

Speakers of this series are often installed in apartments with problematic chimney installations. The intake of air and the removal of combustion products occurs in a location located on the outside of the wall coaxial chimney.

Also installed on the front side electronic control panel. This makes it possible to monitor the performance of the column (in case of a malfunction, information about the malfunction is displayed on the panel), as well as set the minimum error in water temperature - 1 degree.

The productivity is in the range of 12-18 liters of water per minute. The main disadvantage is that if there is no electricity, the speaker will not work.

Columns of the Therm 4000 S series do not require the installation of a chimney.Thanks to the presence of a fan, forced draft is provided. Installation of a coaxial chimney requires the help of a specialist

Series Therm 6000 O

Used in this series of gas water heaters built-in hydro generator allows automatic ignition of the flame when the water tap is opened.

On the front side there is a liquid crystal display that displays the temperature of the leaving water. However, this parameter is set mechanically using a regulator. The productivity of water heaters in this series is 10, 13 and 15 liters of water per minute.

The Therm 6000 O series water heater is equipped with HYDRO POWER technology, thanks to which there is no need for batteries or a piezoelectric element for ignition. The maintained water temperature is displayed on the front panel

Series Therm 6000S and 8000S

These models were made for public use (kitchens of restaurants and canteens, public baths, showers in industries, hospitals, factories). They are able to provide hot water to up to 5 points without loss of temperature. The display is used to make settings. Ignition for this type is electric.

To ensure the operating power of gas water heaters of the Therm 6000 S series, several fans are used simultaneously. The Therm 8000 S models use condensation technology to efficiently heat the water flow.

Why does the column not light up or go out?

Periodically occurring malfunctions in the operation of these devices are not associated with technical defects, but with depreciation during operation. Like any technical device, geysers need to be periodically Maintenance.

List of main faults:

• it is impossible to start up on the first ignition attempt;
• wick fading;
• extinguishing of the igniter when changing the water supply power of the faucet on the mixer;
• weak water heating;
• The pilot light goes out periodically;
• weak water pressure through the geyser pipe system.

If these malfunctions occur, it is not necessary to contact a specialist, because some of them can be solved independently by following a certain operating algorithm and following safety rules.

To solve the problems that arise, you will need to remove the outer casing of the speaker. Regardless of the type, before removing it is necessary to unscrew the fasteners

Problem #1 - The flame does not light on the first try

First, it’s worth doing the most basic things - checking the position water and gas supply valves. If there is no supply of one of them, the operation of the column is blocked automatically.

If batteries are used to start the column, you need to check their functionality. And in case of discharge replace with new batteries.

Provided the problem persists, the next step is to check the chimney. Any ingress of debris and even a large accumulation of soot on the walls of the chimney can lead to a failure - lack of draft. Keeping the chimney clean is a necessity that will prevent carbon monoxide from entering the interior.

If there is no draft sensor that constantly monitors the draft level during operation, you can check its presence yourself. It is enough to use a burning match, which must be brought to the hole in the column. The absence of flame displacement will indicate a blockage in the ventilation system. We turn off the column and clean the chimney.

Another reason could be weak water pressure. This is visually determined when the tap is opened.

If the pressure is sufficiently strong, the problem may be:

• contamination of the water system strainer;
• in contamination of the water system itself;
• finding a blockage in the mixer filter.

If the first problem can be easily solved by washing the mesh filter, then to solve the second and third problems it will be necessary to unscrew the pipes at the inlet, first turning off the gas and water supply, and flush the system. special cleaning agent.

To solve the problem of contamination of the mesh filter, it is necessary to remove the water unit, disassemble it, thoroughly clean and rinse the mesh

The next reason is weak gas pressure. Under no circumstances should this problem be corrected on your own. You should definitely contact specialists.

Incorrectly configured igniter may cause the column to malfunction. This occurs when the gas pressure in the line does not match the type of igniter. If the pressure is low, the gas required for ignition goes down. For more stable operation of the ignition system, it is necessary to mount the electrode that produces the spark to the center of the burner.

Problem #2 - damping of the geyser wick

The problem is when the wick goes out when working in a Bosch geyser, it may be caused by a weak gas supply. This problem may be caused by ignition tube contamination particles of dust and soot.

To solve this, you need to remove the body of the gas water heater and properly disconnect the ignition tube. To clean the inside of the tube, it must be blown out. The edge on which carbon deposits have accumulated is cleaned with sandpaper or other grinding material.

If popping noises that are uncharacteristic of normal operation occur when switching on, you should check the position of the ignition wick flame. Popping noises occur when the fire does not ignite immediately, causing excess gas to accumulate. This problem should be fixed immediately by calling a professional.

When reinstalling, it is necessary to restore the tightness of the tube by connecting it to the required limit with the gas supply tube.

Problem #3 - speaker attenuation during operation

There are situations when a brand geyser Bosch suddenly goes out and stops working, it is necessary to determine how long after ignition this occurs.

If it turns off immediately after startup (after 3-5 seconds), then most likely the problem is ionization sensor failure. In this case, it is necessary to check the wiring between the sensor and the control board and, if it is working properly, replace the sensor.

When the column goes out after several minutes of operation, this may be due to:

• weak gas thrust;
• sensitivity of the alarm relay.

You can check the gas draft in the entire gas system by turning on the gas stove. If the gas supply is visually normal, then the problem is in the gas supply system to the column. To solve it, you need to call a specialist.

Also, the draft problem can be caused by a clogged chimney or heat exchanger tubes clogged with scale.

When scale, soot and soot accumulate on the walls of the heat exchanger, the color of the burning flame changes. Instead of blue it becomes yellow. To eliminate the malfunction, it is necessary to remove the casing and clean the heat exchanger

Another reason may be impaired functionality emergency relay. To do this, you need to open the windows and properly ventilate the room.Then try to start the device again. If the column starts working again, then the problem is the sensitivity of the relay. This element needs to be replaced.

Mixing the flow of hot water with cold water can also cause the column to fade. In order to eliminate this problem, it is necessary to perform the adjustment correctly.

Problem #4 - the gas water heater igniter goes out

One of the important elements of a water heater is the igniter. It is necessary for the smooth functioning of the device, so it must work continuously.

To understand why in the gas water heater goes out igniter, you need to check the following probable causes:

• thermocouple malfunction;
• the appearance of external air flows;
• chimney contamination.

To stop the unstable operation of the gas water heater, an element is used - thermocouple. This is a safety device whose function is to timely shut off the gas flow. If the igniter goes out, it shuts off the gas supply.

Thus, when a thermocouple burns under prolonged exposure to fire, its tip becomes friable, its physical properties are lost, and the protective function is involuntarily triggered. The faulty part must be replaced.

Another reason for insufficient heating of the thermocouple is the gas injector hole being clogged with dust. After cleaning, performance is restored.

When eliminating the problem of the extinguishing pilot light of a gas water heater, you need to be focused and soberly assess your capabilities. If you are unsure of your abilities, it is better to contact a specialist.

If ventilation is improper, the resulting air currents can blow out the pilot burner.It is important here not to confuse this phenomenon with a lack of draft due to contamination of the chimney. To fix the problem, you need to check that the protective cover of the column is correctly attached and that there are no external sources of air exposure.

It should be remembered that modern devices contain a lot of electronic devices, sensors and modules. A separate faulty operation of any of them can lead to failure of the device. Special equipment is required that can detect the malfunction.

Prevention of geyser malfunctions

In addition to troubleshooting, you need to know how to properly disassemble a gas water heater. These skills are necessary to carry out DIY maintenance. Why do you need to know not only the constituent elements, but also the sequence of actions when disassembling the column.

You can perform all maintenance items on a geyser without the help of a technician. The main thing is to follow the sequence of actions and do everything quite carefully

Carrying out periodic preventive maintenance throughout the entire operational life of the gas water heater will contribute to correct operation.

Annual cleaning is recommended in the technical documentation by the manufacturer. After all, it is the lack of cleaning during prolonged use that can lead to all of the above problems.

Conclusions and useful video on the topic

This video shows how to properly clean the pilot tube:

In order to understand the complete step-by-step disassembly, just watch this video:

Gas water heaters Bosch are widely used to solve an important household problem - lack of hot water.In order for these devices to operate smoothly longer, they must be maintained. And malfunctions that arise during operation can be eliminated independently, just know the correct algorithm of actions.

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If the flame does not ignite in your Bosch gas water heater and you can’t find the reason, and you don’t want to call a specialist, ask our experts and other site visitors for advice.