Error codes for the Master Gas boiler: decoding symbols and troubleshooting guides

Master Gas Seoul South Korean gas boilers are structurally complex functional devices with rich technical equipment. Compact units are literally crammed with devices that ensure stable operation of the equipment and automate the process. All components of the system are important and interconnected, but any of them may fail.

The error codes of the Master Gas boiler will help you learn about the occurrence and the cause of the malfunction. The alphanumeric combinations that appear on the display will tell you where the violation occurred, and will quickly decide what should be done to eliminate it. It is extremely important not to lose time when restoring the unit's operability. Do you agree?

We will talk about how the malfunction of the boiler is coded by the manufacturer. Let’s show you what actions to be taken to correct the situation. From the article we presented, you will find out what kind of repair is needed to restore the unit and which of the shortcomings in the work can be eliminated with your own hands.

Briefly about the device and functional systems

Founded in Kazakhstan, Daesung Celtic Enersys Co. Ltd. » offers a Russian consumer a line of wall-mounted gas boilers serving facilities ranging from 110 to 210 m². Double-circuit units from South Korea with the Master Gas Seoul logo and the following letter designation from 11 to 21 are adapted to domestic operating conditions.

In fact, they are a thoroughly thought out and carefully equipped mini-boiler room. It has its own systems of protection, stimulation of the movement of the heated medium, removal of air jams and combustion products, and other devices.

Despite the high quality of the assembly, as well as a meticulous selection of components and parts, periodically one of them becomes unusable. Violations in the work occur due to the banal wear and tear, the completion of the working resource, etc. Unfortunately, the list of common reasons also includes an incorrect attitude of owners to complex technical equipment.

In addition, the units process gas in order to produce heat. And this type of fuel is extremely toxic, therefore it is worth approaching breakdowns seriously. Any violation can lead to undesirable threatening consequences, which are best prevented in the initial stages.

Before proceeding to decipher codes that indicate a malfunction, you should carefully familiarize yourself with the design features, device and components of the gas boiler

Important components responsible for the operation of the wall-mounted boiler model include:

• Burner block. Located in the combustion chamber. Consists of a burner and a manifold with gas injectors. He is responsible for the preparation of the gas-air mixture, more precisely, for mixing blue fuel with air in the fractions required for normal combustion.
• Ignition Candle. Located to the left of the burner. When activated, it produces a spark that sets fire to a gas-air mixture.
• Circulation pump. It stimulates the movement of the coolant along the circuits located inside the boiler and “pushes” after heating to exit to the heating system and the hot water supply pipe.
• Expansion tank. It takes into account the volume of coolant that forms when water is heated. This eliminates the excess pressure that could lead to depressurization of the circuits.
• Air vent. The device for the automatic discharge of air plugs from closed piping systems contributes to the creation of a stable pressure without excess and pressure drops.
• DHW temperature and flow sensors. Used to automate the process. The first fixes the upper and lower limits of heating to send a command to turn on / off the burner. The second gives a signal about the transition to the supply of sanitary water at the time of opening the tap.
• Heating temperature sensor. Reacts to changes in coolant temperature. Automates the procedure for heating it.
• Gas valve. Regulates the supply of gas to the combustion chamber through the nozzles of the gas manifold. It blocks the supply of fuel to the burner in the event of a threatening situation.
• Pressure meter. It controls the pressure of water, gives commands to turn off the unit when the pressure drops or exceeds.
• Fan. Stimulates the withdrawal of gaseous fuel processing products into the chimney.The air pressure switch is responsible for the operation of the fan itself, which, in the absence of draft, stops the boiler.
• Spark plug Detects the presence of flame when the burner is running. If the fire goes out for any reason, this device will issue a command to shut off the gas supply.

Each of the listed devices performs its own front of work. In addition to them, there is still an important group that prevents the occurrence of dangerous situations. These include a safety valve, a thermal relay, eliminating the overheating of heat exchangers, and other equally important details and system components.

Decoding codes and ways to deal with failures

Immediately, we note that serious violations in the operation of the heating gas unit should be eliminated by employees of the organization with which a contract was signed for servicing gas equipment.

All actions of amateurs inside the “mini-boiler room” are strictly prohibited. Simply put, if you need to remove the casing from the gas boiler to fix the problem, you should not "climb" it yourself.

However, the owners must know what happened to their device in order to decide whether to call the master or if the problem is solved by banal cleaning of the appliance clogged with soot. Let's consider what errors the manufacturer encoded and what should be done if the code appeared on an electronic board.

Factory Coded Violations and Errors

Error A2. This is a signal of a malfunction in the fan.

There are three reasons for the failure:

• The device is not receiving power. Check the wiring that the fan is equipped with and the connections. It is possible that contact is simply broken somewhere.
• The fan is out of order. It does not matter if he worked his own or broke for another reason, the fan will have to be changed. If he "flew" during the warranty period, then the gas workers must deliver a new one.
• Blown fuse. With this device, everything is extremely simple. It must be changed immediately.

Regardless of the type of breakdown, the boiler will be stopped by a pressure switch. Indeed, due to the inoperability of the fan, caustic poisonous smoke can enter the premises. The owners need to turn off the boiler and call the master from the service center.

A fan is an important component of a gas heat generator. His responsibility is the removal of products of processing of blue fuel in order to obtain thermal energy.

Error A3. Pump break warning.

If the pump stops working, heated coolant It doesn’t go to heating appliances, and hot sanitary water to faucets. The standard consequence of error A3 is the shutdown of the Master Gas boiler by a thermal relay. For a blocked unit, you will need to buy a new pump.

The most economical and humane option for damage to the owners is a violation in the wiring. If the wire is pinched somewhere or the contact is removed, the master will quickly correct and start the equipment.

If the pump is in good condition and the wiring is not damaged, which can be ascertained by checking, and the thermal relay disables the boiler, the reason is not the pump at all. This means that the thermal relay itself requires replacement.

The Grundfos circulation pump almost never leaves the standing position. All his problems are most often associated with violations of the electrical circuit.

A4 error. Blocking the boiler by a tripped thermal relay.

Thermal relay - a protective device that responds to overheating of the heat exchanger. Most often, the temperature rise in the Master Gas boilers and the A4 error that pops up on the display occurs due to a pump breakdown. If the coolant does not circulate, the boiler continues to heat it. As a result, the water in the heat exchanger boils and the unit is blocked.

Note that overheating occurs not only because of a pump breakdown. Often it occurs due to slow movement in pipes "overgrown" with mineral deposits. The owner of the autonomous system can clean the heating himself, but it is better for the master to remove the "growths" from the heat exchanger.

The thermal relay blocks the unit in case of fixing the overheating of the coolant or sanitary water. If heating is carried out in the normal mode, and the relay turns off the boiler, then you will have to change it

It should be remembered that the performance of cleanings does not belong to the list of warranty obligations of the manufacturer of the technical product. They are carried out at the expense of the owners, therefore it is better to prevent sedimentation on the walls of the pipes. To do this, try not to change the coolant in the system without a visible need.

Error A5. Coolant pressure drop.

If the error code A5 appears on the electronic board or on the control panel display of the Master Gas boiler, it means that the heating circuit sharply pressure decreased.

This violation also has three reasons:

• Airlock. Often they appear when filling the heating fluid, less often when boiling water and a broken thermal relay. The user can remove the air plugs by bleeding through Mayevsky cranes at the batteries. It is necessary to start bleeding to the device furthest from the boiler.
• The heating pressure sensor has broken. If bleeding air from the radiators does not help, you will have to change the coolant pressure sensor.
• The connection between the sensor and the electronic board is broken. To identify the exact cause and place of the open circuit connection, check all the contacts and wiring between the control board and the sensor.

In short if you let the air out of the batteries, and this did not help, turn off the boiler and call customer service.

The pressure sensor detects the excess of standard indicators in the system and transfers information to the control board, which turns off the boiler. Timely blocking of work protects the unit from depressurization of nodes, increases its working resource

Error A6. Ignition does not work.

There are plenty of reasons for this error, most of them are associated with the deposition of combustion products on a candle or with a violation of the wiring:

• The burner block is clogged. It is required to clean the burner and gas nozzles from soot and soot. For cleaning, a burner with a collector is removed from the gas chamber and brushed. Carbon from candles of ionization and ignition is cleaned with fine sandpaper. Then they wipe everything with a damp cloth and brush the internal channels with a brush.
• Ignition plug does not work. It may either be faulty itself or the wiring connected to it may be damaged. If the electrode of the candle is simply covered with soot, it must be cleaned, the device itself must be wiped and degreased.
• The ionization candle does not work. There are two possible solutions: either the catfish “flew” or the wiring somewhere went away.
• The ignition transformer does not work. The situation is like with candles: it is broken and needs to be replaced, or somewhere there is no contact in the electrical circuit.
• Disrupted gas supply. This is the most serious and dangerous of the causes of error A6. It requires a mandatory appeal to gas workers, unless, of course, you yourself forgot to open the gas valve at the gas inlet to the boiler.

In the event of interruptions in the supply of gas to the burner, contacting the gas company is mandatory for those whose boilers are supplied with main gas.

And the owners of autonomous systems must first check the pressure in gas tank or cylinders. Now, if everything is in order with the gas source, you should already call the masters from the service company.

It is the responsibility of the flame ionization plug to register the combustion process in the combustion chamber. If it detects an extinction, the boiler will stop immediately and the gas supply will be shut off.

Error A7. Damage to the gas valve.

Violations of the functionality of the gas valve are traditionally associated:

• With a break of the modulator coil. There is nothing to be done, you have to change the valve completely.
• With damage to the electrical circuit. You need to check all the contacts and wires for a poor connection or a broken wire.

For check gas valve for operability, one of the wires is disconnected from the modulator coil. If, after reconnecting, the blinking A7 on the display does not disappear, get ready to purchase a new device and to replace it.

A gas valve is needed to adjust the flow characteristics of the fuel. If it is unsuitable for further use, it is replaced

Error A8. Non-extinguishing flame after turning off the burner.

If, after stopping the heating process, a small non-extinguishing flame remains in the combustion chamber, then the gas valve has become unusable. Simply put, the diaphragm located inside the valve is damaged. It is not possible to change it. Need to buy a new valve.

Error A9. Anti-freeze mode.

The system is designed for continuous operation in the cold period, even if the boiler itself is turned off. If the coolant temperature drops below the limit declared by the manufacturer, it starts the burner to keep the minimum temperature background. When the temperature drops to + 5º C, in addition to the burner, the automation will also start the circulation pump.

If the boiler shows A9, it is necessary to configure and start this mode again. Each owner can do this himself, without calling the master.

Error AA. The temperature sensor of the heating circuit has tripped.

If the temperature sensor installed in the heating circuit has tripped and transmitted a signal to the thermal relay to lock the boiler, it means that the water in it has heated above + 95º C and is about to boil.

The occurrence of an AA error on the display of the Master Gas Seoul device is facilitated by:

• Overhead communication taps. You need to check if you forgot to open the path for the movement of the coolant, make-up and supply of water before switching on the unit.
• Filter clogged. Having switched off the boiler, it is necessary to test the heating filter. If it is clogged with mineral sediment, the coolant does not move because of it. Clean and rinse thoroughly under running water.
• Damage to the pump. Replacement of a device that stimulates the flow of water through a closed system is required.
• Inoperative three-way valve. Need to replace the device that distributes the flows for heating and DHW.
• Broken duct sensor. An instrument that records incorrect readings in the domestic hot water circuit should be replaced.

If you do not quickly correct the situation and eliminate the causes, then the consequences can be most dire: from a violation of the tightness of the pipes to the irreparable failure of the unit.

In order not to constantly have to remove the filter of the heating circuit for cleaning, it is necessary not to create conditions for the appearance of sediment in the system. The easiest way is not to drain and fill the circuit without real need

Error Ab. Damage to the temperature sensor of the heating circuit.

If the temperature sensor that detects the coolant is defective, the device itself or the electrical connections that supply it with energy should be checked for functionality.

They check it in the same way as a gas valve - disconnect one of the contacts with the boiler turned off. The appearance of this error on the display after starting the boiler indicates that it is not in it, but in the wiring.By testing all contacts and wires, they find damage and repair.

Error Ac. Damage to the temperature sensor of the DHW circuit.

The reasons and their search are made in the same way as all these measures are done with a sensor that records the temperature in the heating circuit. If this error appears when disconnecting the wire, then the sensor itself is intact. Therefore, he did not work due to a break in the electrical circuit.

Temperature sensors record the upper and lower temperature limits of the heated medium (coolant or sanitary water). If the user-defined settings are reached, the boiler is started or paused

Error Ae. Violation of the air pressure switch.

The failure of the pressostat has three main causes:

• Clogged channels. Moreover, you need to check both the chimney and the air supply pipe to the closed combustion chamber. In the case of using a coaxial chimney, only it is checked. If identified, immediately clean the air supply and exhaust products by the gas boiler.
• Violation of the wiring. It is possible that one of the contacts is loose or the wire is damaged.
• Damage to the pressure switch itself. If, at a pressure drop of 130 Pa, the device’s contacts do not close, it means that it is itself defective. Will have to change.

However, in addition to the errors listed above, there are also violations in the operation of South Korean boilers for which codes have not been developed and adopted. Meanwhile, to know about them is very useful.

Abnormal operation of the boiler without an error code

If your Master Gas boiler refuses to turn on, no error code will appear on the remote control display or on the electronic board. In this case, you need to check whether the equipment is connected to the network, if the socket or power cable is damaged.

If error codes are not displayed on the remote control or on the electronic board, then one of these control devices is faulty. This is most often due to water ingress.

After making sure that everything is in order with the power supply, but the boiler still does not turn on, proceed to inspect the electronic board. It is possible that water got on it. To dry, it is better to use a hair dryer, after which you need to leave the device for a couple of days so that all residual moisture completely evaporates.

Also, the preconditions for a sudden stop of the boiler include blown fuse. This part wears out quickly. As a rule, it is subject to trouble-free replacement.

If popping in the burner is detected, pay attention to the condition of the gas burner. Usually it begins to clap if serious cleaning is required. True, this may happen due to improper adjustment of the gas valve - the minimum pressure will need to be corrected.

If it is not possible to achieve comfortable conditions with a correctly set coolant temperature, it is most likely dirty or defective temperature sensor. Cleaning is required, if it does not help, replacement.

In case of insufficient output of heated sanitary water from the double-circuit gas boiler, it is worth checking the pressure. It is possible that low pressure in a centralized system from which water is supplied to the boiler. However, a dirt sump on the water line may clog or a secondary heat exchanger, the one called the plate heat exchanger, may become clogged.

A service representative should regularly clean the gas burner with a manifold. To remove dust with a rag, to clean a deposit with a fine emery paper, to release internal channels from burning

If you enter the house / apartment, you feel an unpleasant gas smell, then there has been a leak. The main thing here is not to lose your head and time. Immediately you need to open the window and wide the door to form an air stream, then call the emergency gang. In no case should you light the light, strike it with matches or a lighter! Any spark will cause an explosion.

Baksi will introduce decryption of codes of violations in the boiler next article, which we advise you to read not only to potential buyers, but also to all equipment owners.

Conclusions and useful video on the topic

The following video will introduce the rules for servicing South Korean boilers of Master Gas Seoul brand:

The rules and specifics of decoding errors are extremely useful information that allows you to quickly respond to all possible violations in the operation of the boiler. Nevertheless, the owner will have to face the first with all kinds of failures. Him and decide on further actions.

Have a desire to share your own experience in decoding errors of the Master Gas boiler and promptly resolving the problem? Have useful information not listed in the article? Please leave comments in the form below the block, ask questions and post thematic photos.