Condensing Boiler Radiant R2KA 34/20 Manual – Complete PDF Guide

The Radiant R2KA 34/20 condensing boiler is a model where the water vapor in the exhaust gases is condensed. This allows for the recovery of the latent heat of condensation and consequently greater energy efficiency compared to a traditional boiler.

This boiler also features a Storage system that:

• Reduces the time for hot water to reach the faucet.
• Has greater long-term resistance to limescale.
• Performs better in the case of simultaneous use of hot water from multiple outlets.

However, the storage requires higher gas consumption to maintain temperature and necessitates anti-legionella treatment.

Annual Boiler Maintenance

Annual maintenance is indispensable to preserve the safety, efficiency, and reliability qualities of your device. This annual intervention prevents malfunctions and ensures the continuous safety of the system.

Winter Boiler Maintenance: Complete Guide

• Pressure Check: Ensure that your Radiant R2KA 34/20 boiler’s pressure gauge shows adequate pressure.
• Thermostat Maintenance: Regularly check the thermostat batteries to avoid malfunctions during the colder months.
• Heating System Pressure: Check that the pressure is maintained between 1 and 1.5 bar for optimal operation.
• Professional Support: For thorough maintenance and cleaning of your Radiant R2KA 34/20 boiler, always contact qualified personnel.

Check the Heating System’s Pressure

At least every quarter, ensure that the system’s pressure is correct; it should be between 1bar and 2bar. Also check this in the summer, as the boiler uses radiator water (only in internal circulation) to heat domestic hot water. If the pressure is low, the boiler is equipped with a component that stops the production of heating or hot water.

Remember to use the filling tap, found under the appliance. Open it and check that the pressure gauge reaches 1.5bar, then close it.

Suggested Temperatures

The Radiant R2KA 34/20 boiler can always produce the temperature you want for heating according to your needs. You can adjust the temperatures via the control panel, but we suggest setting the hot water temperature (DHW) to the minimum necessary due to limescale and domestic hot water (DHW) considerations.

Attention to temperature settings:

• The heating temperature setting refers to the radiator temperature, not the ambient temperature.
• The domestic hot water temperature setting should be kept as low as possible to avoid calcification inside the secondary heat exchanger.

Preventing Limescale in Showers: Filters and Shower Heads

Preventing limescale buildup in shower head aerator filters is crucial for maintaining an efficient sanitary system. Excessive buildup can complicate the removal of aerators and lead to unwanted overheating. We recommend regular replacement of these elements to preserve the functionality of the Radiant R2KA 34/20 boiler.

Preparing Your Boiler for the Holidays

Before leaving for the holidays, it’s essential to take precautions to ensure the safety and efficiency of your Radiant R2KA 34/20 boiler. Even the latest models are not immune to possible leaks.

Here are some recommended measures:

• Close the domestic hot water supply valve to prevent possible water leaks.
• Shut off the gas supply to prevent safety issues.
• Turn off the heat generator to reduce energy consumption and increase safety.

Upon your return, restore all these settings in the reverse order. You will likely need to rearm the heat generator to resolve any ignition errors caused by the shutdown.

These simple actions will allow you to enjoy your holidays with greater peace of mind, knowing that your home and boiler are safe.

Maintenance and Assistance Made Easy

The R2KA 34/20 boiler makes maintenance a straightforward process. The user interface, developed in collaboration with NORDGAS, allows for quick identification of any issue thanks to a well-structured error reporting system. The boiler is designed to facilitate daily maintenance operations and remote diagnosis.

Easy Diagnosis and Error Resolution

Common problems like no flame, thermal fuse interruption, or lack of water are easily identifiable thanks to clear error codes displayed on the panel. This enables a quick response and, if necessary, efficient technical intervention. Additionally, features such as the anti-freeze and the FAST-H2O system ensure stable operation and reduce the frequency of maintenance.

• Error 01: No flame, which can occur if the gas tap is closed or if the meter has been changed. Press the button. In all other cases, if it does not restart, call a technician.
• Error 03: Flue side thermal fuse tripped. Press the button. If it does not restart, call a technician.
• Error 04: No water in the system. Refill the system via the black cylindrical tap under the boiler, keep an eye on the pressure gauge above the display, and close the refill tap when the pressure reaches 1.2 or 1.5 bar. The error resets itself, followed by an approximately 2-minute venting procedure. Please wait.
• Error 18: Insufficient circulation. This error may be caused by particularly dirty magnetic filters. Check the magnetic filter at the boiler inlet with a technician to restore the circulator flow rate.

Notifications

These refer not to errors but to functions currently in operation:

• F08 Anti-freeze function for heating active: If the boiler is external and reaches a very low temperature, this procedure activates to prevent the technical water from freezing. Please wait for the operation to complete.
• F33 System Venting Cycle: This usually happens during the reset of error E04. Once the {manufacturer} R2KA 34/20 boiler pressure is restored, it performs this function for about 2 minutes. Please wait for the operation to complete.
• FH Fast H20: The boiler is preparing to preheat the sanitary water. Please wait for the procedure to complete.

Energy Efficiency and Quietness

{manufacturer} has revolutionized energy efficiency with its boiler series, offering exceptional performance in terms of both gas and electricity consumption. These models, besides being extraordinarily quiet (about 55 decibels), boast reduced gas consumption, thanks to their 9 flame modulations and proportional temperature control. Electrical consumption is also minimized, thanks to the modulating WILO circulator and optimized standby consumption.

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 R2KA 34/20 device.

Safety in the Use of Electric Energy

It is essential to adopt precautions when using the R2KA 34/20 boiler to avoid risks:

• Do not handle the appliance with wet or damp hands, nor walk barefoot in its vicinity.
• Handle electrical cords carefully to avoid damage and malfunctions.
• Do not leave the appliance outdoors exposed to rain or sun, unless it is specifically designed for this purpose.
• If the cord is damaged, immediately turn off the appliance and contact a qualified technician.

Remember that only authorized personnel should install and maintain the appliance. Unauthorized maintenance or improper use can invalidate the warranty and compromise safety.

What to Do in the Presence of Gas Odor

In situations of potential gas leakage, it is crucial to follow these guidelines:

• Avoid using any electrical device that could trigger sparks, including the phone.
• Immediately ventilate the environment by opening doors and windows.
• Close the gas taps to stop the leakage.
• Promptly call for urgent intervention by expert and qualified personnel.

The boiler should be used exclusively according to the manufacturer’s instructions and for heating water to safe temperatures. Improper use can cause serious damage. Ensure that installation and maintenance are entrusted to authorized technicians to avoid risks and ensure compliance with safety regulations.

List of Components and Spare Parts

In this guide, you will discover everything there is to know about the different components and spare parts of the R2KA 34/20 boiler: how to identify them, their specific function, and useful tips for maintenance and replacement.

Temperature Adjustment

On the control panel of the Radiant R2KA 34/20 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 Radiant R2KA 34/20 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).

Preventive Maintenance of the 20-Liter Stainless Steel Boiler

The 20-liter stainless steel boiler from the {manufacturer} R2KA 34/20 boiler offers optimal hot water production thanks to its efficient internal coil. To preserve its performance and lifespan, accurate maintenance is fundamental.

A key aspect of this maintenance is the periodic replacement of the sacrificial anode, vital to protect the boiler from corrosion. This intervention significantly prolongs the boiler’s life and maintains its operational efficiency.

Ignoring the replacement of the anode can cause serious damage to the boiler, including malfunctions and leaks. It is strongly advised to respect the manufacturer’s maintenance guidelines and regularly check the condition of the anode.

Energy Saving with the Modulating Pump for Boilers

The introduction of variable speed modulating pumps in modern boilers is a revolution in terms of energy saving and cost reduction. These pumps, regulated by an advanced electronic system through a second connector, are capable of varying their speed from 0 to 100% according to the real needs, maximizing the efficiency of the system. Their use, mandatory in new boilers, demonstrates a commitment to solutions that combine excellent performance with care for the environment and household economy.

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 Radiant R2KA 34/20 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.

3/8 Automatic Air Purger

The 3/8 automatic air purger is a fundamental component in the Radiant R2KA 34/20 boiler to ensure the elimination of air in the heating system. This small but essential device plays a critical role in maintaining the efficiency of the heating system.

Despite its low cost, this component is vital to ensure that there is no trapped air in the radiator system, especially for aluminum ones, where the presence of air can be a frequent problem, particularly after long periods of inactivity like during the summer.

Checking the functionality and replacing the air purger is always advised to prevent circulation problems at the beginning of the heating season. Its efficiency 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 R2KA 34/20 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.

Possible Improvement Works

The condensing boiler Radiant R2KA 34/20 requires special attention to the correct installation of the flue pipe. Especially in horizontal sections, condensation can form, compromising the functionality of the fan. It is not uncommon to see installations where the flue pipe (especially if corrugated) forms a siphon, causing the boiler to produce very loud noises. 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 R2KA 34/20 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 Radiant R2KA 34/20 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 Radiant R2KA 34/20 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 R2KA 34/20 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 magnetic filter should be applied on the heating return line to the boiler, separating everything that could clog the boiler and cause temperature increases in the primary exchanger. The diverter valve is also less stressed, and the adoption of the magnetic filter could prevent its leakage.

Maintenance of the Polyphosphate Doser

If the tap water hardness exceeds 20 French degrees, a polyphosphate doser is recommended for the Radiant R2KA 34/20 boiler.

The polyphosphate doser, which can use powder or liquid additives, is vital for reducing limescale in the Radiant R2KA 34/20 boiler. These additives require constant replenishment to ensure maximum effectiveness.

Available in different variants, polyphosphates include:

• Powder Polyphosphates
• Liquid Polyphosphates

The choice of polyphosphate determines the type of mixing mechanism required.

Thermostat and Programmable Thermostat

Maximize comfort and efficiency of your Radiant R2KA 34/20 boiler by installing a room thermostat or programmable thermostat.

These smart devices allow you to customize your home’s temperature, ensuring a pleasant environment and reducing energy consumption. Particularly, programmable thermostats allow you to set different temperature settings for each day of the week or specific times of the day.

Available models include:

• Daily Programmable Thermostats
• Weekly Programmable Thermostats
• Smart Thermostats with Remote Control

Choose the model that best meets the needs of your home and your Radiant R2KA 34/20 boiler.

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 Radiant R2KA 34/20 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.

INFO MENU DISPLAY DATA

To view the boiler data from info menu you just have to press the INFO key. The info code will be displayed on the left side of the screen and its relative value will be displayed on the centre of the screen.
Use keys ‘ + ’ and ‘ – ’ of the heating circuit to scroll through the list of displayed data. To exit display mode press the INFO ‘ i ’ key.

Anomaly Reporting Codes R2KA 34/20

To display the last 5 anomaly reporting codes, from the most recent in chronological order, activate OFF mode using the central button and hold down the INFO button for 5 seconds. To scroll through the list of stored anomalies, use the PLUS and MINUS buttons of the heating system. To reset the anomaly history, press the RESET button. To exit the display environment, press the INFO button.

Common Questions and Answers About the Boiler

Here is a list of common questions and answers that we frequently receive about the Radiant R2KA 34/20 boiler model. This section will help you better understand the features, functionality, and maintenance 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.

Loud Noises During Operation

If your Radiant R2KA 34/20 boiler makes loud noises during operation, first check the system pressure. Too low a pressure can be the cause. Otherwise, in this condensing boiler, it could occur due to lack of maintenance.

Indeed, the heat exchanger tends to slightly oxidize during operation and over time a large amount of dirt can accumulate in the condensate siphon. Regular maintenance is essential to reduce the risk of noises or machine shutdowns.

Does the boiler support the Opentherm protocol?

YES: The boiler’s thermostat contacts are voltage-free (no tension) and can communicate with an Advanced Thermostat or Remote Control.
This allows you to:

• Set the domestic hot water temperature: Especially useful if the R2KA 34/20 boiler is difficult to reach (attic, basement, external technical room).
• Set the radiator temperature: In addition to room temperature, the advanced Opentherm chronothermostat can communicate with the boiler to adjust radiator temperatures.
• Set operating hours for domestic hot water: Useful for boilers with storage tanks, it can save on boiler maintenance costs (like gas).
• Error Management: With Opentherm 2 or with proprietary remote control from Radiant.
• 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.

Downloadable Manuals

• Technical Manual for Radiant R2KA 34/20 Boiler