Boiler Euroterm AURA MEB K 28 S PDF Manual – Complete Guide for Use and Maintenance
The Euroterm AURA MEB K 28 S condensing boiler utilizes the process of condensing the water vapor contained in the exhaust gases to recover heat. This technique greatly increases energy efficiency compared to traditional boilers.
Distinctive features of this boiler include a Storage system that:
- Shortens the delivery time of hot water.
- Ensures better resistance to limescale over time.
- Provides optimal performance even with simultaneous uses of hot water.
However, consider that the storage implies higher gas consumption to maintain temperature and requires specific anti-legionella treatment.
General Usage Information
To maintain the safety, efficiency, reliability, and performance characteristics that distinguish the device, it is necessary to perform annual maintenance. Annual maintenance is essential for the safety and continuous use of the AURA MEB K 28 S device.
Warnings for the Use of Electric Energy
For safe use of the boiler, it is important to follow some basic rules:
- Do not touch the appliance with wet or damp body parts and avoid doing so barefoot.
- Avoid pulling electrical cords and ensure they are not damaged.
- Do not expose the appliance to adverse weather conditions such as rain or direct sunlight, unless otherwise indicated.
- In case of damage to the electric cord, immediately turn off the appliance and contact a qualified technician for replacement.
Additionally, ensure that the boiler is installed, put into operation, and maintained by authorized technicians to guarantee the validity of the warranty and safety in use. Improper use of the appliance and any unauthorized alterations could pose safety risks.
Safety Actions in Case of Gas Detection
If a gas odor is detected, it is fundamental to adopt these precautionary measures:
- Do not use electrical appliances, including phones, that might generate sparks.
- Immediately open doors and windows to facilitate air exchange.
- Stop the gas supply by closing the taps.
- Immediately request the intervention of a specialized technician.
It is important to use the AURA MEB K 28 S boiler exclusively for the purposes for which it is designed, avoiding improper uses that can be dangerous. Ensure that any intervention on the boiler is carried out by qualified personnel to prevent accidents and maintain the warranty.
Guide to Components and Spare Parts
This section is dedicated to providing a complete overview of the various components and spare parts available for the AURA MEB K 28 S boiler. You will find detailed information on each part, from its main function to advice on when it might need to be replaced.
Features of the AURA MEB K 28 S Boiler Display
Discover the features and symbols of the AURA MEB K 28 S boiler display, a panel rich in information. Key commands:
- PLUS and MINUS Thermo: Adjust the radiator temperature, independent of the ambient temperature.
- ECO/COMFORT: Choose between ECO/COMFORT1/COMFORT2 settings for sanitary water.
- RESET: Solves errors (excluding water shortage) and allows menu access.
- SUN/SNOWFLAKE: Switch for Summer and Winter seasons.
Display indicators:
- SUN/SNOWFLAKE: Indicates the seasonal mode of the boiler.
- ECO/COMFORT: Active mode for sanitary water.
- 1.2 bar: Real-time pressure level of the boiler.
- Drop Symbol: Represents the flame’s power, increases with flame intensity.
- Upper Temperature: Shows the temperature of the primary circuit, important also in summer for DHW.
- Lower Temperature: Current temperature of sanitary water.
ACS Production Configurations in the Boiler
The boiler offers various options for producing domestic hot water (DHW), thanks to the integration of micro-accumulation and the COMFORT mode, available from the control panel. Modes include ECO, COMFORT1, and COMFORT2.
Details of ECO Mode
In ECO mode, the boiler activates DHW production on demand. With the opening of a tap, the boiler starts up, regulating the flame based on water flow for precise temperature control. However, the wait for hot water can be prolonged due to micro-accumulation.
Details of COMFORT Mode
COMFORT mode, in both its variants, offers preheating of DHW. COMFORT1 allows for manual temperature adjustment, while COMFORT2 maintains a stable temperature at 45 degrees.
Temperature Adjustment
On the control panel of the Euroterm AURA MEB K 28 S condensing boiler, you can find all the operational information. You can set the temperatures for heating or hot water by pressing the + and – buttons next to their respective symbols: Faucet and Radiator. After pressing, the boiler displays the set temperature for only a few seconds.
Normally, the boiler shows the flow temperature, to be interpreted as the internal temperature of the boiler. As a result, you will see the temperature rise even in summer when the Euroterm AURA MEB K 28 S boiler produces hot water, while in winter it can be interpreted as the current temperature of the radiators.
Using the + and – buttons at the top for heating and at the bottom for domestic hot water, you can choose the desired temperatures for heating. We suggest:
- From 25°C to 38°C if you have underfloor heating.
- From 55°C to 65°C if you have radiators made of aluminum or steel.
- From 45°C to 60°C if you have cast iron radiators.
For domestic hot water, you can choose the temperature using the + and – buttons at the bottom. We suggest a temperature between 38 and 45°C.
The general advice for the temperature of domestic hot water is to keep it as low as possible, especially if your water supply provides very hard water (over 30°F).
Error Guide
- Error A01: If the flame locks, especially after changing the gas meter, press the Reset button for a reset. If it does not resolve, it is necessary to call support.
- Error F37: Check the pressure via the pressure gauge. If it is below 0.8 bar, there is a lack of water. To correct, increase the pressure at the filling tap to 1.5 bar. FH will appear on the display as confirmation of the reset.
- FH: This wording is shown when the boiler begins the expulsion of air from the technical water, a process that normally takes two minutes after adjusting the pressure.
Innovative Monoblock Silicon-Aluminum Heat Exchanger
The modern monoblock exchanger, made from silicon-aluminum, is characterized by a light, compact structure, with wide flue channels that greatly simplify cleaning and maintenance.
It stands out for its resistance to thermal shocks and excellent thermal exchange, with efficiency up to 108%. However, careful maintenance is required:
- Removal of deposits and dust from the combustion chamber.
- Keep water inside the exchanger to avoid blockages.
- In the event of serious blockages, the exchanger can cause noises and CO2 issues.
- Use an alkaline gel cleaner for particularly loud noises.
The alkaline GEL cleaner can be found on e-commerce sites like Amazon.
Grundfos UPS15/60 Pump Performance
Enhance the performance of your AURA MEB K 28 S boiler with the Grundfos UPS15/60 pump, designed for superior water circulation. Choose from three speed levels to maximize efficiency, with the third speed recommended for the best performance, except in the presence of circulation noises.
The pump, generally easy to install by a professional, may present difficulties in removing the stator from the cast iron head after a long period of use.
Technical specifications of the Grundfos UPS15/60:
- Power Supply: 2.5 μF 230V – 50Hz IP44 TF 95
- High Speed (III): 0.38 A – 85 W
- Medium Speed (II): 0.30 A – 65 W
- Low Speed (I): 0.21 A – 45 W
Suitable also as a replacement for models UPS 15-50, 15-60, 25-50, 25-60, 15-65, 25-65.
Automatic Plastic Air Purger
The plastic automatic air purger, used as an insert in the purging housing in the pump manifold, is a key component in the Euroterm AURA MEB K 28 S boiler. This small element plays a vital role in ensuring the efficiency of the heating system by eliminating air from the system.
Made of durable plastic, this air purger is designed to easily fit into the dedicated housing in the pump manifold. Its use is particularly recommended to prevent air accumulation in the boiler’s hydraulic circuitry, especially in systems with a lot of aluminum where this problem is more frequent after periods of inactivity (summer).
Regularly checking and replacing the air purger and the system pressure is essential for maintaining uninterrupted operation at the start of the heating season. Its functionality is crucial for the proper operation of the entire domestic heating system.
Safety Systems according to the ErP Directive
The construction and installation of boilers in Europe are strictly regulated by a series of European standards, aimed at ensuring safety, energy efficiency, and reduction of environmental impact.
One of the main reference regulations is the ErP (Energy-related Products) Directive, which imposes stringent requirements in terms of energy efficiency and emissions for all energy-related products, including boilers. This directive is accompanied by specific UNI EN standards for each type of boiler, detailing the technical and safety standards to be respected.
The AURA MEB K 28 S boiler therefore includes:
The Safety Thermostat, located on the heating supply, intervenes by blocking the gas flow to the burner in case of overheating of the water in the primary circuit. It is essential to never deactivate this safety device.
The Flame Ionization Detector ensures safety by shutting down the boiler in case of gas absence or incomplete ignition of the main burner.
The Antifreeze Device activates the burner to maintain the water temperature above 5 °C, preventing freezing of the system.
The Hydraulic Safety Valve, set at 3 bar, protects the heating circuit. It is advisable to connect it to a siphoned drain and not use it to empty the circuit.
Anti-Legionella Treatment in AURA MEB K 28 S Boiler
The mandatory anti-Legionella treatment in the AURA MEB K 28 S boiler is crucial for ensuring the sanitary safety of water and preventing the formation of Legionella bacteria. This system, which automatically initiates a sterilization cycle according to the electronic board’s programming, is essential for the health and safety of the user. Deactivating this mechanism is strongly discouraged as it could lead to significant health risks due to the potential proliferation of Legionella bacteria in the water storage.
Possible Improvement Works
The Euroterm AURA MEB K 28 S boiler requires special attention to the proper cleaning of the flue pipe. Especially at the bends leading to the vertical section, dirt can accumulate, compromising the functionality of the smoke fan. It is essential to have a qualified technician ensure that the pipes are in optimal condition.
Integrating a Gas Tap with a Test Well
Not always does the meter provide a connection for instrumental tightness testing. A useful tip is to replace the gas tap under the boiler with a valve with a well equipped with an instrumental take-off, essential for the tightness test of the system. This element can be crucial in case of inspections and safety checks and certainly facilitates the maintenance of the AURA MEB K 28 S boiler.
In fact, during the maintenance of the appliance, it is mandatory to perform a suitable test like UNI 11137:2019 that verifies the correct tightness of the gas system.
Flushing the Heating System
Flushing the heating system is crucial to prevent clogging of the primary exchanger of the Euroterm AURA MEB K 28 S boiler. Over time, especially in cast iron or aluminum systems, a metallic sludge can form that can clog the narrow passages of the exchanger.
After flushing the system, it is highly recommended to install a magnetic sludge filter on the Euroterm AURA MEB K 28 S boiler. This filter plays an essential role in protecting the exchanger from the buildup of dirt and debris, ensuring greater efficiency and longevity of the heating system.
Additional improvements can include the installation of an advanced thermostat with relay function. This device allows for more effective management of heating hours, helping to optimize energy consumption.
Suggested Accessories
You might consider a range of accessories that would enhance the functionality of the AURA MEB K 28 S boiler.
Magnetic Filter for Heating
Considered the best accessory to block the entry of dust and debris from the heating system into the device.
The use of the magnetic filter in the heating return line is a strategic choice to protect the boiler. This device uniquely captures and isolates both magnetic and non-magnetic debris that could otherwise accumulate and cause malfunctions. Keeping the filter clean and functional is essential to ensure maximum efficiency of the boiler and to prevent common issues such as temperature increase and excessive stress on the diverter valve.
Polyphosphate Dosing Pump
If the hardness of the tap water exceeds 20 French degrees, we suggest equipping the boiler with a polyphosphate doser.
This powder or liquid additive is proportionally mixed with the cold water entering the boiler and decreases the formation of limescale inside the device. Polyphosphates need to be replenished whenever they run out.
There are various models, but the most common ones are:
- Powder Polyphosphates
- Liquid Polyphosphates
Clearly, the type of polyphosphate requires a suitable mechanism for mixing.
Room Thermostat and Programmable Thermostat
For optimal temperature control in your home, consider installing a thermostat or programmable thermostat for your boiler.
These devices allow you to regulate and program the temperature precisely, adjusting it to your daily needs. A programmable thermostat, in particular, offers the possibility to set different programs for specific days and times, optimizing comfort and reducing energy costs.
There are various models available, including:
- Daily Programmable Thermostats
- Weekly Programmable Thermostats
- New Generation Thermostats with Remote Control
The choice of model depends on your specific needs and the configuration of your heating system.
Daily Programmable Thermostat
The daily programmable thermostat is an effective solution for daily temperature control in your home.
This device allows you to set the desired temperature for each individual day, enabling flexible management adaptable to your daily routines. It is ideal for those seeking simple yet precise control of home heating, with the ability to adjust settings according to variations in their daily schedule.
Typical features of a daily programmable thermostat include:
- Easy and intuitive programming
- Precise temperature adjustment
- Energy-saving functions
This type of thermostat is an optimal choice for those who want to combine comfort and energy efficiency without the need for complex weekly programming.
Weekly Programmable Thermostat
For advanced and personalized home temperature management, the weekly programmable thermostat is an excellent choice.
This device allows for setting different temperatures for various days of the week, perfectly adapting to different weekly routines. It is ideal for those who need detailed heating control, with the ability to set lower temperatures on days when the home is empty and higher when it is occupied.
Key features of the weekly programmable thermostat include:
- Flexible programming for each day of the week
- Advanced energy-saving functions
- Intuitive user interface for easy programming
A weekly programmable thermostat is perfect for those seeking a balance between comfort, convenience, and energy efficiency, providing precise control of the home climate.
Advanced New Generation Thermostats
New generation advanced thermostats offer cutting-edge technologies for optimal home climate control.
These devices stand out for their learning capability and adaptation to user habits, automatically adjusting the temperature based on daily and seasonal patterns. With features like remote control via smartphone and integration with home automation systems, they offer an unprecedented level of convenience and energy efficiency.
Salient features of these thermostats include:
- Wi-Fi connectivity and remote control
- Integration with voice assistants and smart home systems
- Learning algorithms for automatic temperature optimization
For those seeking the utmost efficiency, convenience, and personalization in home temperature control, an advanced new generation thermostat is the ideal choice.
Magnesium Anode
The magnesium anode is the primary solution for preventing corrosion in the Euroterm AURA MEB K 28 S boiler’s accumulation tank. This highly reactive component protects the boiler’s metal parts from oxidation, ensuring longevity and efficiency.
It is important to periodically replace the magnesium anode, depending on the water conditions and the usage of the boiler.
Possible Effects of the Magnesium Anode
Rarely, due to strong electrical influences:
- The magnesium anode may wear out very quickly.
- Due to rapid consumption, a lot of air may form and exit the tap after long periods of non-use (night).
- A slight sulfur odor may be detected after several months of boiler inactivity.
The effects related to air tend to subside shortly after the first few weeks of maintenance. However, it can be resolved at the next maintenance opportunity by preferring an aluminum anode, which also has a longer lifespan.
Frequent Questions
To help you resolve doubts and questions about your Euroterm AURA MEB K 28 S boiler model, we have prepared a list of Q&A covering the most common issues. Find the answers you are looking for optimal use of your appliance.
Hot Water takes forever to reach the shower/bathroom !!
The delay in hot water reaching the bathroom is often caused by a buildup of dirt in the aerator or showerhead holes. This buildup can reduce water flow, consequently slowing down the flow of hot water in the pipes. Cleaning these accessories from limescale can usually restore the speed of the hot water arrival.
Additionally, if the pipes connecting the bathroom to the boiler are made of iron, they might absorb some of the water’s heat, lengthening the time for hot water to arrive. The presence of iron pipes can thus affect the timing of hot water delivery to the bathroom.
What is the difference between COMFORT 1 and COMFORT 2?
The manufacturer offers two COMFORT functions for the AURA MEB K 28 S boiler, activated through the ECO/COMFORT1/COMFORT2 button.
- Comfort 1: In this mode, you can adjust the domestic hot water temperature using the + and – buttons (near the faucet symbol).
- Comfort 2: In this mode, the temperature is fixed at 45°C without the possibility of adjustment.
Opentherm Protocol Support by the Boiler
YES: The boiler is equipped with non-powered thermostatic connections, compatible with Smart Thermostats or Remote Controls. This allows the use of advanced functions such as:
- Adjusting the domestic hot water temperature: Ideal for AURA MEB K 28 S boilers installed in hard-to-reach areas.
- Adjusting the radiator temperature: With the Opentherm chronothermostat, it is possible to adjust the radiator temperatures directly from the boiler.
- Setting operating times for domestic hot water: A feature that helps to reduce the maintenance costs of the boiler for models with storage tanks.
- Fault Management: Using the Opentherm 2 protocol or a specific remote control from Euroterm.
- etc…
Pressing the buttons to adjust the heating, the temperature does not change.
The button panel is sensitive to repeated presses after years of operation. Often, the malfunction of the adjustment buttons is due to the absence of a thermostat, which has led to the exclusive use of the boiler’s buttons.
In light of this, it is suggested to install a new control board to restore the correct functioning of the button panel, but also to integrate a thermostat to continue adjusting the heating from another, more reliable, and less expensive device.
