How to choose an electric boiler or ORAVA convector – what to focus on
How to choose an electric boiler or convector ORAVA – a complete guide for everyone
When a customer comes with the question "I want to heat electrically, what should I buy?", the answer is never simple. At first glance, it seems clear – you choose a boiler or convector, connect it, and that's it. But in practice, there are fundamental differences between these two categories in heating philosophy, installation requirements, investment costs, and daily comfort. And precisely because ORAVA offers both solutions, it is important to understand what each of them does, for whom it is intended, and what you can realistically expect from it. This article will take you through all the essentials – from technical parameters through selection according to the building layout to specific products and their strengths.
Two philosophies of electric heating: boiler vs. convector
Before we get into specific products, it is necessary to understand the fundamental difference. The ORAVA electric boiler is a central heating device – it heats water, which circulates through radiators or floor heating just like with a classic gas boiler. Heat is therefore transferred by water, the heating system is hydraulic, and the boiler serves as a heat source for the whole house.
The ORAVA convector is a decentralized solution – each unit heats the space in which it stands or is installed on the wall. Air passes through an electric heating element and the heated air mass circulates in the room by natural convection. No water, no pipes, no radiators.
This distinction is crucial, as it affects every aspect – from installation, through consumption, regulation, to investment costs. More about the comparison of both approaches can be found in the topic ORAVA electric boiler vs. convector – which type of heating is more cost-effective.
For whom is the ORAVA electric boiler intended and what to expect from it
An electric boiler is a logical choice in situations where you have an existing water heating system and are looking for a replacement for the original heat source – for example, an old gas boiler, when it no longer makes sense to pay for gas, or a solid fuel boiler, which you no longer want to maintain. In these cases, an electric boiler fits into the existing infrastructure without the need to break walls or disrupt existing piping.
An electric boiler is also a solution for new buildings, where the investor wants a central heat source but does not have a gas connection or has decided on an emission-free solution. These are typically chalets, weekend homes, smaller family homes up to 120–150 m², or recreational buildings.
What does the ORAVA electric boiler offer compared to other sources? First of all, simplicity. No chimneys, no emissions, no fuel tank, no gas appliance inspection. Installation is significantly simpler and cheaper than with a gas boiler. Operation is quiet and the device has no moving parts that would wear out quickly. The disadvantage is operating costs – electricity is more expensive than natural gas calculated in kWh of heat, so correct regulation and ideally a heating tariff are key. More about consumption and cost optimization can be found in the topic ORAVA electric heating and energy consumption – how to reduce heating costs.
When an electric boiler is not suitable
An electric boiler is not a solution for everyone. If you heat a building with high heat loss (an old house without insulation, ceilings over 3 m, large window areas), the costs of heating with an electric boiler can be unaffordable. Likewise, if you do not have sufficient capacity at the electrical connection point – larger boilers require three-phase power and a supply with sufficiently dimensioned circuit breakers – a costly upgrade of the electrical installation may be necessary. I always recommend first checking the actual condition of the connection and the heat loss of the building.
Specific models of ORAVA electric boilers – what each of them brings
Currently, two main models of electric boilers are available in the range. Both share the basic construction philosophy, but differ in power, functions, and target group.
ORAVA EK-2003 is a more powerful model suitable for larger heating systems. It is a three-phase boiler with electronic control, continuous power regulation (which is very important from an economic point of view – the boiler does not operate at full power all the time, but adapts to the current heat demand), built-in thermostat and protections against overheating and low pressure. This boiler is suitable for larger houses or for customers who want to have a power reserve for possible future extensions or higher heat demand in extremely cold winters.
ORAVA EK-2004 is a model with a modified power configuration, suitable for smaller to medium-sized buildings. In practice, I have encountered cases where a customer bought a more powerful boiler "just to be safe" and then found out that the boiler was working in short cycles (quickly heats up, turns off, heats up again), which is energy inefficient and increases equipment wear. Correct sizing is therefore crucial – more on this in the topic What power of ORAVA electric boiler do I need for my household.
Who is the ORAVA convector suitable for and its advantages in practice
The convector is a solution that will be appreciated especially by those who do not want or cannot build a complete water-based heating system. Typical situations from practice: a rented apartment without central heating, a cottage or weekend house where you heat only occasionally, a garage or workshop, a new addition to a house where running pipes does not make sense, or office spaces.
The ORAVA convector has several practical advantages over a boiler. Installation is simple – all you need is an electrical socket or a fixed connection to the electrical grid. No hydraulic system, expansion tank, circulation pump, or air venting is required. The device reacts to temperature changes faster than a water system. From the perspective of regulation – each room has its own thermostat, so you can maintain different temperatures in different rooms without complicated hydraulic regulation.
A disadvantage of the convector is that when heating a larger house, you will need multiple units, each with its own electrical installation, and the total investment costs can be comparable to a boiler solution. Also, the air movement – typical for convectors – may bother some people (dust, dry air). Therefore, for comfortable whole-house heating, most professionals ultimately prefer a boiler solution.
ORAVA convector models – what they specifically offer
ORAVA VL-202 is a modern wall-mounted convector with an electronic thermostat and the possibility of precise temperature setting. It has several power levels, an LCD display, and a weekly programmer. This is a key feature for economical heating – the convector can automatically lower the temperature during the night or during your absence and then reheat the room to the desired temperature before your return. In terms of design, it is a thin, discreet device suitable for modern interiors.
ORAVA VL-201 is a more compact model suitable for smaller spaces or as an additional heat source in rooms where basic heating is insufficient. Simpler control, mechanical thermostat, low-cost installation. In practice, this model has proven itself, for example, in bathrooms (where heat is needed only in the morning and evening), in hallways, or in guest rooms.
More on how to correctly set up the convector and make full use of its regulation functions can be found in the topic Regulation and temperature setting of ORAVA convectors – how to properly control heating.
Criteria for selection step by step – what to ask before purchasing
Selecting the right product does not start in an online shop, but at home with a piece of paper and a calculator. Here is the process I recommend to every customer:
1. What type of building and heating system is available?
If you have existing radiators connected to a water circuit, the clear choice is an electric boiler – either ORAVA EK-2003 or ORAVA EK-2004 depending on the required power. If you have no system and are building from scratch (or it is a cottage, garage, or addition), a convector is a simpler and cheaper way to start. An exception is a situation where you plan to also install underfloor heating – in this case, a boiler solution is justified even in a new construction.
2. What is the area and heat loss of the building?
This is the most important technical parameter. Heat loss depends on the area, ceiling height, insulation thickness, window quality, and climatic region. As a rough estimate: a well-insulated new construction requires about 40–60 W of heat per m², while an older house without insulation may require 80–120 W/m². For a house with an area of 100 m² and a calculated heat loss of 7 kW, you do not need a boiler with a power of 14 kW – you would be wasting investment and the boiler would operate inefficiently in short cycles.
3. What is the capacity of the electrical connection point?
An electric boiler with a power output above 3.6 kW requires three-phase power supply (400 V, 3×16 A or more). If you have only a single-phase connection (230 V) in the building, you are limited to a maximum output of approximately 3.5 kW, which is sufficient only for very small spaces (up to about 35–40 m² in a well-insulated house). Therefore, always check the value of the main circuit breaker and the type of connection before purchasing a boiler.
4. How will you control the heating?
A boiler solution with room and outdoor thermostats can be very energy efficient, but it requires proper setup. A convector with a weekly programmer (such as ORAVA VL-202) provides direct control over each room separately. Think about what suits you best – central control or decentralized flexibility.
5. What is the intensity of the building's usage?
For a cottage that you visit only occasionally, a convector is ideal – simply turn it on before arrival (or set it to remote control, if the model supports it). For a permanently occupied house, a boiler solution is more comfortable and, for large areas, also more cost-effective in terms of investment in individual units.
6. Are you interested in the preparation of hot water for domestic use?
Certain models of electric boilers can also control a hot water storage tank (DHW). If you do not want to have a separate electric water heater, find out whether the boiler model you are considering supports this function. A convector does not provide DHW preparation at all.
Electrical installation – what must not be forgotten
One of the most common mistakes I see in customer orders is underestimating the electrical installation requirements. An electric boiler is not just a "big kettle" – it is a device with power ranging from several kW to ten kW, which must be connected to a separate circuit with protections corresponding to its power and load characteristics.
For the ORAVA electric boiler, the following general requirements apply: a separate electrical circuit protected by a circuit breaker with characteristic B or C (according to the manufacturer's specifications), a conductor dimensioned according to the maximum power of the boiler, a residual current device (RCD) with sensitivity 30 mA, and earthing. If you plan to connect the boiler to a night tariff or a heating tariff (HDO), the electrician must connect the control via an HDO relay. This is not a job for a layperson – it must always be performed by a qualified professional. More details can be found in the topic Installation of the ORAVA electric boiler – procedure, requirements, and what the electrician must do.
For convectors, the situation is simpler – most smaller models are plugged into a standard 230 V socket, but even here, when higher power or fixed installation is involved, the connection must be done by an electrician and the installation must meet the requirements of the STN 33 2000 standard. The procedure and common mistakes are thoroughly discussed in the topic Wall mounting of the ORAVA convector – instructions and common installation mistakes.
Hydraulic connection of the electric boiler – what you need to know
Along with the electrical installation, the electric boiler must also meet hydraulic requirements. The boiler is connected to an existing or new heating circuit and requires several components without which it cannot operate safely:
- Expansion tank – compensates for the expansion of water when heated. The tank volume is calculated according to the water volume in the system. An undersized expansion tank causes the boiler to trip repeatedly on the safety valve.
- Pressure relief valve – a safety component that releases pressure in case of a control failure. The opening pressure must correspond to the system's operating pressure (typically 2.5 bar for home systems).
- Circulation pump – ensures water circulation. Some ORAVA boilers have a built-in pump, while for others, an external pump with power and characteristics matching the system must be connected.
- Air vent – located at the highest point of the system or on the boiler itself. Air in the system is the most common cause of noise and uneven heating of radiators.
- Filling valve and pressure gauge – for monitoring and topping up the water pressure. The operating pressure of a cold system is typically 1–1.5 bar, and for a hot system, 1.5–2 bar.
In practice, I see situations where a customer replaces an old boiler with an electric ORAVA boiler but forgets to check the condition of the expansion tank. An old tank after years may lose its membrane and the new boiler passes through it – the result is that the boiler reports an overpressure error every day. Therefore, when replacing a boiler, I always recommend checking the entire system, not just the heat source itself. More about common faults and their causes can be found in the topic Common faults of ORAVA electric boilers and how to eliminate them.
Control, programming, and smart control
Modern ORAVA electric boilers and convectors offer several levels of control. At the boiler level, you typically have a room thermostat (comfort thermostat) that turns the boiler on and off according to the temperature in the reference room. Some models also support an outdoor sensor – the boiler then adjusts the water outlet temperature according to the outdoor temperature (equithermal control), which is an energy-efficient solution.
With convectors, the control is local – each convector has its own thermostat and (in the case of model VL-202) also a weekly programmer. This allows you to set different temperature settings for workdays and weekends, for daytime and nighttime. For example, if you sleep in the bedroom at 18 °C and want the living room to be 22 °C over the weekend, you can achieve this with convectors without any additional equipment.
It is important to understand that each degree of temperature reduction during the night or absence will save real money. As a rough estimate, a reduction of 1 °C reduces consumption by approximately 5–7 %. For a house with monthly heating costs of 150 €, this means savings of 20–30 € per month with properly programmed setbacks, without any compromise in comfort.
Maintenance and long-term reliability
Electric boilers ORAVA have significantly lower service requirements compared to gas boilers. No flue passages, no burner inspection, no flue gas analysis. Despite this, there are tasks that should not be forgotten:
- Water pressure check – recommended once a month. A pressure drop below 1 bar indicates a leak or a problem with the expansion tank.
- Draining radiators – best done at the beginning of each heating season. Air in the system causes noise and uneven heating.
- Checking the anode (if available) – in some boiler models with an integrated TÚV storage tank. The anode protects the tank from corrosion and should be replaced every 2–3 years.
- Checking the heating element – limescale from hard water deposits on the heating element reduce its efficiency. In areas with hard water, consider water softening or regular chemical descaling.
- Cleaning filters and valves – a dirty filter before the boiler (if installed) should be cleaned regularly.
Convector heaters are practically maintenance-free – it is enough to occasionally clean the intake grill from dust, as neglected dust on the grill reduces air flow and prolongs the heating time of the room. Detailed information can be found in the topic Maintenance and service of the ORAVA electric boiler – what and how often to check.
Economic comparison – investment and operation
Investment costs for a boiler solution are higher – in addition to the boiler itself, you pay for hydraulic installation, an electrician, possibly the replacement or addition of an expansion tank and other valves. As a rough estimate, expect to pay 400–800 € for the complete installation of an electric boiler in a family home with an existing system, plus materials. In a new build, the costs for piping are significantly higher.
A convector is a cheaper investment – the installation on the wall is a matter of an hour of an electrician’s work (for a fixed connection) or even a layperson (for a plug-in connection). However, if you need 6 convectors for 6 rooms, the total investment quickly equals the boiler solution.
Operating costs depend primarily on the price of electricity, the efficiency of the regulation and the heat loss of the building. Electricity is more expensive than gas per kWh of heat, so electric heating is economical mainly in well-insulated buildings with low heat loss and with proper regulation. If you are considering an electric boiler or convector in an old, poorly insulated house, the numbers are likely unfavorable – consider insulation and window replacement first.
Most frequently asked questions (FAQ)
Can I connect the ORAVA electric boiler myself, without an electrician?
No. An electric boiler is a dedicated electrical appliance with a power usually exceeding 3.6 kW, which must be connected by a qualified person in accordance with current standards (Decree No. 508/2009 Coll., STN 33 2000). In addition to the safety risk, this may also void the warranty and cause complications in the event of an insurance incident. The hydraulic part can be done yourself if you have sufficient experience, but the electrical connection must be performed by an electrician.
What is the difference between a single-phase and a three-phase electric boiler?
A single-phase boiler is powered from one phase of 230 V and its maximum power is limited to approximately 3.5 kW (with a 16 A circuit breaker). A three-phase boiler uses three phases of 400 V and can have a power of 6, 9, 12 or more kW. For larger buildings, a three-phase solution is essential. Always check before purchase whether your building has a three-phase connection.
Can I leave the convector on low power overnight?
Yes, ORAVA convectors are designed for long-term continuous operation. In fact, it is more energy-efficient – maintaining a lower temperature (e.g. 16–17 °C) in the room during the night is more economical than allowing the room to cool down and then heating it up to full power in the morning. The model VL-202 has a built-in weekly programmer directly in the device.
How do I know that my ORAVA electric boiler has a problem and needs service?
Typical signs of problems: the boiler repeatedly turns off and displays an error code, the low-pressure indicator blinks on the display, radiators in some rooms are cold despite the boiler working, the circulation pump makes unusual noise, or the boiler heats water more slowly than usual. Most faults can be diagnosed according to the error code in the manual. More detailed diagnostics can be found in the topic Common faults of ORAVA electric boilers and how to eliminate them.
Is a convector with a mechanical or electronic thermostat better?
An electronic thermostat (as in the model ORAVA VL-202) is more accurate – it maintains the temperature with a deviation of ±0.5 °C from the set value, whereas a mechanical thermostat typically has a deviation of ±2–3 °C. An electronic thermostat also allows programming and saves more energy in the long run. A mechanical thermostat, however, is more resistant to power outages (it continues operation after power is restored) and does not require any settings. For a permanently occupied room, I recommend an electronic one; for a cabin or spaces with occasional use, a mechanical one is sufficient.
Can I use the ORAVA electric boiler to prepare hot water for domestic use?
It depends on the specific model. Some boilers have an output for controlling an external TÚV storage tank (boiler) – the boiler switches the heating from the heating system to the TÚV tank at a set time and heats the water to the set temperature. If this function is not available, you will need a separate electric water heater. Always check the technical specifications of the specific boiler model.
Conclusion – the right choice depends on the overall context
Choosing between an ORAVA electric boiler and a convector is not a question of which product is "better". It is a question of which product better suits your specific situation – the type of building, existing infrastructure, usage intensity, financial possibilities, and comfort requirements. An electric boiler is the right choice where you have or are building a central heating system and need a reliable, comfortable, and well-regulated heat source. A convector is ideal for spaces where a water-based system does not make sense, or where you need a fast, flexible, and investment-friendly solution.
If you are unsure which solution is right for you, I recommend first reading the topics in this Knowledge Center – especially Common questions about ORAVA electric boilers and convectors and What power of ORAVA electric boiler do I need for my household. Proper preparation before purchase saves time, money, and unnecessary complications during installation.
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Can't decide or are you dealing with a specific situation in your household? Write to us – we are happy to help.