Hydrosta gas boiler - error codes, their meaning and recommendations for troubleshooting

Design and operating principle of Hydrosta boilers

South Korean gas boilers from Hydrosta

, like Daewoo, running on diesel and gas, automated double-circuit, designed to heat rooms up to 500 square meters and provide them with hot water.

The fuel burns almost completely, thanks to the turbocharged burner used. The automation itself maintains the specified air and water temperature conditions. For Hydrosta operation, 4 operating modes are taken into account: simple, time-interrupted, “home alone” and hot water supply mode.

All models are equipped with double protection against overheating, against freezing and control over the flame in the combustion chamber (furnace). The boilers make it possible to attach a gas leak meter - this is done in a remote version and makes it possible to remotely control the state of gas in the heated room.

If a leak is detected, a sound signal and light indication are given, and the gas supply is immediately cut off. The self-diagnosis system displays all potential errors on the remote control. The room control panel makes it possible to make adjustments at a distance, up to a distance of 50 meters from the boiler. An electronic timer greatly improves efficiency.

All boilers use a closed firebox. And clean air enters through a coaxial chimney from the street. Before gas enters the burner, ventilation is performed with a built-in fan. Then the speed is reduced, and the gas is supplied for combustion, where it is mixed with air.

Then a high voltage is applied to the electrodes, and the gaseous mixture ignites from the spark that appears. The ignition of the gas is secured by an IR sensor, and all subsequent work is controlled by the control board.

Electrodes for Hydrosta

The heat is absorbed by the copper pipe coil and the pump ensures uniform circulation. Burnt products are also removed outside using a fan. All models are equipped with separate DHW heat exchangers, or otherwise - secondary plate heat exchangers. Their task is to prepare only domestic hot water.

In such boilers, only one will work - either heating or hot water. This approach is very durable and as a result, devices are less likely to break down. The heating priority in models of this type is carried out according to DHW, the temperature of which can be from 35 to sixty degrees. The coolant has a temperature of 50 to 80 degrees, and on the control panel you can set the required air temperature in values from 5 to 40 degrees.

The productivity of Hydrost and DAEWOO is considered very high - for hot water from 10 to 27 liters per minute of 25 degrees. If you need to get a 40-degree temperature, the productivity will be from 6 to 40 liters per minute, depending on the selected power of the device.

All boilers under consideration will usually operate on both natural and liquefied gas; you only need to replace the spray device. During operation, gas
boiler generates different error codes, depending on the breakdown.

Identification of errors and malfunctions in Hydrosta gas boilers

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Error code E1 - This is a sign of low pressure in the system. Probable causes of this malfunction: low fluid pressure in the heating circuit. The contact between the control board and the pressure sensor is broken. The pressure switch is faulty. The first step is to look at the results of the pressure gauge reading. In many cases, the problem is eliminated using a make-up tap, which is designed to fill the heating system with coolant. Error code E2, E4 - No traction. In order to ensure stable and reliable operation of the device, it is necessary to provide draft to remove combustion products so that they do not penetrate into the room. The exhaust of gases is controlled electronically, and when any problems occur, the draft sensor-relay is triggered and the boiler will be turned off. Possible reasons why there is no draft: insufficient diameter of the chimney duct, defective installation, blockage, icing of the inner wall. Reducing the size of the outlet channel serves as a factor in reducing traction. The flue pipes are too long. We advise you to carefully study the installation instructions for the gas unit and follow all the necessary requirements. A very long horizontal outlet of the chimney pipe may cause a lack of necessary draft. Failure of the pneumatic traction sensor - When a vacuum occurs in the inlet tube, you can hear a characteristic click. There is no contact between the electronic board and the draft sensor, the presence of condensation, as well as incorrect connection of the tubes to the pneumatic relay. Error code E3 - Khudrost boiler is overheated. The device is blocked. The overheating safety thermostat turned on - The overheating thermostat, like the temperature sensor, is in most cases located on the outlet pipe of the primary heat exchanger. The functional task of the thermostat is to ensure the safety of the boiler unit from excessive temperature increases. Malfunction most often occurs due to problems in the thermostat, temperature sensor, and also due to problems with the main circulation circuit. Temperature sensor failure - The control board receives an incorrect signal or poor contact between the electronic board and the sensor. The overheating thermostat is faulty - When the sensor is working, but there is actual overheating of the liquid, then most likely there is a violation of the circulation of the heating circuit coolant. The primary heat exchanger or filter element of the heating circuit is clogged (a low level of circulation gives an increased heating temperature of the liquid). The circulation pump is malfunctioning or there is an air blockage in the heating system. Error E5 - Indicates a malfunction of the ignition system. The ionization flame sensor indicates a malfunction of the device. This component detects the presence of a flame and stops the Hydrosta boiler from operating when the main burner is not fully burning or when there are gas supply problems. Blocking occurs after three unsuccessful starts. To resume operation, you must press and hold the R key. Problem with the gas valve - The gas valve is controlled electronically. Diagnosis of this element is carried out by measuring voltage and resistance. If it is determined that the values differ from the nominal characteristics, it is necessary to replace the valve with a functional one. There is no gas flow into the boiler - The gas distribution device has a valve that limits the gas flow. As a result, a failure to start the device may occur due to a closed valve. Poor contact or no signal from the flame ionization sensor. The control board has a malfunction - When ignition occurs correctly, but the device suddenly goes out, it can be assumed that the electronic board does not detect the flame. Based on this, it is recommended to test it. Ignition does not take place. This is displayed when the ignition does not work or the burner flame is extinguished. It is necessary to check the contacts between the ignition device and the flame electrode, and also between the board and the gas valve. The main factor in burner flame extinction is unsatisfactory draft. Error E8 - The heating circuit temperature sensor is not functioning correctly. This code indicates that the heating circuit temperature sensor has failed or the temperature required for operation has increased significantly. The temperature sensor circuit in the heating circuit is damaged - This malfunction occurs when the connection between the temperature sensor and the electronic board is interrupted, or the temperature value is much lower than the required one. Five seconds after identifying a boiler malfunction, Hydrosta will resume operating functions if the malfunction occurred spontaneously. It is necessary to check that there is no moisture on the temperature sensor connector and the electronic board connector. If there is no moisture, the temperature sensor must be replaced. There is a short circuit in the heating circuit temperature sensor - This situation can occur after a short circuit in the temperature sensor circuit or the temperature value of the coolant is higher than recommended. Initially, it is recommended to measure the resistance of the temperature sensor. If the resistance readings differ from the standard ones, you need to change the temperature sensor. When replacing the temperature sensor does not help the result, change the controller. Code E9 - fluid leak. The circulation pump, main heat exchanger, emergency overpressure relief valve, worn gaskets, make-up valve and other components may leak. Leaks can be found by inspecting hydraulic connections and components. EA code - the water replenishment signal is activated more than 5 times within one minute. Code EE - Fan operation suspended - There is a blockage in the fan impeller. There is no sufficient lubrication on the fan shaft, and therefore the required speed is not generated. The contact between the control board and the fan is broken. Error Uo - Boiler restart. Code U8 - Problems with determining the temperature by the DHW sensor. This code indicates that there is a malfunction of the temperature sensor in the DHW circuit or that the recommended temperature is too high. The main reasons preceding this problem: the temperature sensor for the hot water supply has failed. There is no contact between the control board and the DHW temperature sensor. The control board has burned out. When the hot water temperature sensor is intact and firmly connected to the control board, although the device displays an error, then the control board may be defective. A year ago, a Hydrosta gas boiler was connected to the system. Over the last week, the E5 ignition error has been showing up almost regularly. After restarting using the reset key, the device periodically turns on satisfactorily, but this happens sporadically. The other day I removed the air cap and it began to function better. What could be wrong? If a draft error occurs, you need to open the protective covers. This will help draw air from the room. Next, check the chimney pipe for the presence of ice and, if necessary, clean it. In the event of a combustion emergency, you should find out whether gas is supplied to the house. All the time the boiler shows error code E8. Help me figure out what it signals? This code indicates to you that the heating circuit temperature sensor is broken. Most likely, it needs to be replaced. Why won't my Hydrosta wall-mounted boiler start? Error E3 also comes on repeatedly. What to do? Such a malfunction may occur due to any problems with the thermostat, temperature sensor, as well as due to difficult operation of the main circulation circuit. The heat exchanger may be overheating. If the temperature sensor and thermostat are working properly, then the problem is with the electronic board. You must replace it. Why is the device unable to start and error code E1 displayed? The pressure is normal and there are no leaks observed. I disconnect from the power supply, but the emergency does not go away. What's the matter? A fault code usually appears when the coolant pressure in the heating circuit is low. In such a situation, it is necessary to check the water level sensor. It is possible that this is the problem. The malfunction of the unit looks like this: DHW is turned on at 45 degrees. If you use hot water, the burner ignites and then goes out. This process happens all the time. Either warm water or cold water flows from the tap. Error code E3 is issued periodically. What is causing this malfunction? This circumstance indicates overheating of the coolant in the DHW circuit. We assume that the heat exchanger is very dirty, or the thermostat is not set correctly. A malfunction has occurred. At the moment of ignition, the unit goes into error E5. If we reboot it, it turns on normally, but as soon as the burner starts working, several clicks are heard, and then an error is displayed. I changed the ionization electrode, washed the flow sensor, removed the ground from the plug, but the result was zero. Who has encountered this? This problem occurs for several reasons. The flame control electrode has failed. Incorrect gas supply. The electronics board is faulty. The device turned off spontaneously and shows code E1. What's happened? There is no liquid in the unit or the pressure switch sensor is broken. Initially, fill the system with fluid. The gas boiler stops working with error message E4. Blowing and cleaning helped in the short term. What could it be? This code indicates a lack of draft, and the chimney system must be checked. Presumably the membrane is stuck. In other cases, you need to contact the service department for a thorough inspection of the device and then further repair it. There is a Khudrost cauldron in our house. An error with code U8 began to appear. The device itself functions; the liquid temperature level is adjusted manually. When installing it, it seems that overheating occurred, since the temperature maintenance mode was turned on. We did not install an external air temperature sensor. What is causing this malfunction? Presumably, the DHW temperature sensor is damaged. In some cases, the electronic board is damaged. The unit performs work for about four to five minutes, after which the burner device turns off and error E2 appears. It burns for no more than a minute, the gas burner lights up again, and the unit performs its functions well for another three to four minutes, and so on in a circle. This code, based on the operating instructions, means that the draft sensor is triggered, but the chimney channel is not clogged, flue gases come out normally. Can't figure out what's wrong? In a particular case, the main factors for the lack of traction may be: damage to the traction sensor. Lack of contact between the pressure switch and the control board. There is condensation, as well as poor fastening of the tubes with the pneumatic relay. There is a problem with the fan operation. Perhaps it does not develop the required speed.

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BAKSI - REPAIR

After starting, a malfunction appeared. It doesn’t want to turn on, it worked for two years, now the whole display lights up, just like when the boiler is turned on, when the self-diagnosis mode is in progress, then it clicks, turns off for miles and seconds and turns on the whole display again. It turned on once, but it gives error E10 water pressure, although the pressure in the system is 1.5 atm. Tell me, what could it be?

BAXI - OPERATION

In operation, the Baxi main four 240 boiler shuts down with error E35 (stray flame). Tell me what to do? First season in operation.

BAXI - SETTINGS

We installed and connected the Baxi Fourtech 24 F boiler. What cold water pressure is allowed at the inlet to the DHW device?

BOSCH - REPAIR

Bosch 6000 24 kW boiler, single-circuit with built-in three-way valve. The boiler sensor does not see it and gives an error. Tell me how to do it so that it doesn’t give an error and works normally for both the heating and the boiler?

BOSCH - ADJUSTMENTS

If you turn off the DHW flow sensor, maybe it will be possible to reprogram it into a single-circuit device through menu L3?

ARDERIA - REPAIR

We installed an Arderia esr 2.13 ffcd boiler. If my coolant pressure drops slightly by a couple of notches over 2-3 days, could the reason be a faulty three-way valve (there are no leaks from the radiators)?

ARDERIA - ADJUSTMENTS

The gas boiler Arderia 2.35 is in operation. Tell me about reducing power. I heard something about modulation, fan speed, etc. Is it really possible to reduce power?

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BUDERUS FLOOR

We installed and connected the Buderus Logano G234-WS-44 kW boiler, automatic Logomatic 4211. Heating is based on cylinders without hot water, and the jets for reduced gas were also replaced. We survived the winter, the cylinders were replaced, all without problems. Then in the spring, when the outside temperature was +16+18, the boiler began to turn off for a long time and when turned on, it began to display a burner error on the screen and the red button light on the front wall came on. We pressed the button, turned the power back on and everything worked. This happened several times, then the boiler was turned off completely for the summer, what could be the problem?

BUDERUS WALL

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VAILLANT - REPAIR

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VAILLANT - ADJUSTMENTS

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DAEWOO

In operation there is a double-circuit gas boiler Daewoo Gasboiler with an electronic panel. When the DHW is turned on, the heating heats up, the operating mode is summer. I removed the three-way valve, there is no dirt or wear. It seems that the board does not control the three-way valve. How to check?

ELECTROLUX

The Electrolux Basic Xi wall-mounted boiler has been installed and connected. A problem began that the boiler stopped seeing the flame and turned off the gas supply after 7-8 seconds. And after 3 attempts it gave error E1. How can I fix it?

KOREA STAR

Koreastar boiler malfunction. The heating works perfectly, the hot water comes intermittently, when you turn on the hot water tap, cold water comes out first, then boiling water. After a few seconds it’s cool, then boiling water again. What could be the problem?

FERROLI

Malfunction of the Ferroli Domiproject 24 boiler - I set it to 60-70 degrees, it switches to minimum combustion, does not turn on, does not turn off. Restart is unstable. No pattern emerges. What to do?

JUNKERS

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NAVIEN

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OASIS

Malfunction of the Oasis ZRT18 boiler. The unit starts, the gas lights up, then goes out. It lights up again and then goes out (this happens three times). Then it lights up and works fine. It doesn't give any error. What is the reason?

SAUNIER DUVAL

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VIESSMANN

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WESTEN

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BERETTA

The Novella floor-standing gas boiler is blocked - the green lights on the panel are on and nothing else happens. How to fix?

ARISTON

An Ariston gas wall-mounted boiler has been installed and connected, which does not hold pressure at all: while cooling the heated water, the pressure drops to zero, although water is regularly filled. What about the pressure?

SIME

Metropolis dgt 25 bf boiler malfunction. The hot water supply has stopped working, the heating is working, it does not display an error. What do you advise?

SOLLY

Please tell me how to solve the problem. The Solly Standard boiler, whenever you try to turn it on or hot water, displays a GS error.

WOLF

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DEMRAD

In the gas boiler Demrad, the gas supply to the burner stopped. The piezo element clicks, but there is no ignition. There is nothing wrong with the gas stove, there is gas. What is the reason?

KITURAMI

The Kiturami world boiler is malfunctioning and stops periodically. I clean the flame sensor and the unit works fine for a while, but soon the same thing happens again. He also began to smoke heavily. Maybe the problem is that the chimney is short, and it needs to be lengthened?

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IMMERGAZ - ERRORS

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IMMERGAZ - REPAIR

My boiler systematically raises the temperature to 80 degrees in winter mode. I called the repairman three times. He said that many models have this problem and suggested installing a programmer, but it’s not certain that it will help. Tell me how to solve this problem and will this programmer help?

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AOGV - REPAIR

The AOGV gas boiler was installed and put into operation. Problem with hot water supply. The heat exchanger was washed. Less than a month has passed and the water is not flowing again. We put a filter on the water, but time passed, and again there was no hot water. What kind of breakdown could this be?

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ROSS

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ATEM ZHYTOMYR

Tell me, is it possible that due to low gas pressure the Atem Zhytomyr boiler goes out, a click occurs and goes out. What is the problem? Is it possible to temporarily disable automation and how?

LEMAX

We installed a Lemax KSG-12.5 Premium gas boiler. After turning off the main burner, a clicking sound occurs after a couple of minutes, what is the reason? Tell me?

KEBER

A KS-G gas boiler of 250 sq.m. was installed and connected. m. When ignited, it does not turn off, the temperature rises, if I am not mistaken, automatic Arbat 1. The flame is not regulated - it is too large. What to do?

LIGHTHOUSE

I installed the Mayak gas boiler and connected it. It works fine. But the reason is this. When it works on unit it squeaks a lot, if you turn the knob 2-7 the squeak disappears. Tell me, what could it be?

DANKO

We installed and connected a Danko gas boiler with automatic Kare, it works great on the igniter, but as soon as you add power to the burner, it goes out completely, yesterday it went out within 5 minutes, today it works for about 20 minutes and goes out completely. Has anyone encountered this problem?

GAZLUX

The gaseko 18 boiler is in operation. When hot water is turned on, the pressure in the system drops after replenishment, the pressure reaches 3 bar. Have to reset. What's wrong, how to fix it?

NOVA FLORIDA

Water often boils in the boiler, causing it to fail due to overheating. The heat exchanger was recently washed, the system is not clogged. What's the matter?

RINNAI

Rinnai 167 RMF boiler malfunction. Recently I started showing error 14. How can I fix the problem?

CELTIC

The Celtic DS boiler heats up to 45 degrees and sits all day, does not turn off and does not heat the batteries, sometimes it shows error A3. How can I fix this problem?

MORA

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MASTER GAS SEOUL

The Seoul gas wall-mounted boiler stopped turning on due to a no-ignition error. How can it be eliminated? What exactly went wrong?

Key error codes

Error e0 – failure of the room heat sensor. The gas does not ignite properly. You should check whether there is gas in the system and whether the gas valve is closed. Moreover, make sure there is gas in the cylinder or line.

Error e1 – lack of water in the heating system. Small amount of water in the system. You need to make sure there is no problem with the cold water supply system, check the filters and, if necessary, clean or replace them.

Error e3 - the water in the boiler boiled due to overheating. The water in the heating system does not move smoothly. You need to check whether the filter is clogged and whether the shut-off valves are open enough.

Error e4 - the chimney is clogged. Gaseous, liquid and solid substances are not released outside. It is necessary to check the pipe sections of the smoke removal system and, if necessary, clean the pipe or call a professional.

Error e5 - the burner flame does not meet the standard. The automation does not “see” the flame or it does not flare up enough. You should check the flame control meter and adjust the burner flame, or call a professional.

Error e6 - gas leak. Gas is leaving the system. the boiler immediately

and try to detect and remove the cause of the leak on your own, or invite a specialist.

Error e7 - the connection between the thermostatic valve and the control panel is broken. Poor contact or broken cables connecting the thermostat to the control panel. Check the cable connection between the remote control and the thermostatic valve and remove any damage.

Error e8 - the water temperature sensor is faulty. The water heating temperature control meter gives distorted information. Check the problematic component and replace it if necessary.

Her mistake is that the fan is faulty. The fan does not work or becomes dirty. Check the voltage supply to the fan and replace it if it breaks. You should also check it for contamination and clean it if necessary.

Error

ef – the flow switch does not turn off the water for more than an hour and a half. The automation saw the lack of activity for a long time and sent a message. Check the switch, clean and replace if necessary.

Error

ea – a signal to replenish water is received more than 5 times per minute. The automation saw that there was a lot of activity and reported a possible breakdown. It is necessary to check the serviceability of the supply circuit, filters and the presence of the required pressure in the water meter unit.

Water supply filter

Error U0 (uo) – secondary start of the boiler. Boiler

tries to start itself again when a signal of a breakdown appears, which can be eliminated after a specific time or by the consumer on his own.

The main causes and malfunctions of gas boilers

The typical thermal circuit for various gas-fired boilers is almost the same; the main elements of the thermal circuit include a boiler with a firebox and heaters for hot water, one boiler for single-circuit boilers for heating systems and two for double-circuit boilers. Along the gas path there is a burner and chimneys connected to the chimney.

If boilers operate with forced circulation of flue gases, like closed fireboxes, then a smoke exhauster or fan is additionally installed to supply air to the firebox and create a gas-air mixture. The gas pipe system and direct and return water pipelines are connected to the boiler using shut-off and control valves; in addition, automatic safety and regulation devices are installed in the circuit. All these elements must work reliably and in harmony with each other, otherwise the boiler will issue an error code.

Other faults

During operation of a Daewoo boiler, error codes cannot always help with malfunctions.

The following problems may occur:

The room remote control power buttons do not work when the power cord is connected. You should measure the voltage at the signal end of the remote control and at the blue CN terminals. It should be equal to 12 volts. The solution is to replace the defective controls and configure the terminal unit.
If overheating is detected, check whether the circulation pump is working correctly, check the pressure in the heating pipe and the cleanliness of the distribution pipe.
If a pump failure occurs during testing, the mains voltage is measured between the two black-and-white and white-black terminals on the CN pump
When ignition does not occur, the locking condition and operation of the control panel are inspected. The operation of the main board is also checked. Diagnostic points for this are indicated in a special table in the operating instructions.

Characteristics of floor-mounted devices

Let's look at the example of Hydrosta HSB. They look like this: These mechanisms have the same characteristics as the wall-mounted options, but they are characterized by higher performance and additional functionality :

The heat exchanger is made of stainless steel, which significantly increases the service life (up to twenty years).
Reducing noise level. The functioning of the mechanism was based on the forced injection of air and the removal of waste after combustion. A special unit of the device - a muffler - reduces the intensity of noise.
The Hydrosta HSB double-circuit mechanism is installed in places with a large volume of heating area. Equipping with a built-in storage container significantly reduces the time for warming up the liquid.

Mounted boilers

Technical characteristics of mounted units:

The heat carrier is completely protected from freezing.
The wall-mounted version has a multi-level security system.
Sealed firebox design.
Hot water circuit. Equipped with two separate heat exchangers. They improve the performance of the device.
Operating principle. Warming up the exhaust gas is used to produce heat in larger quantities.