Electric convectors Protherm vs. Tesy: what are the differences and which one to choose
Electric Convectors Protherm vs. Tesy: Detailed Comparison of the Two Most Popular Brands
When a customer walks into a store or opens an online shop with electric convectors, the first two brands they almost always encounter are Protherm and Tesy. Both have a long history, decent distribution, and enough positive reviews to earn the trust of Slovak households. Nevertheless, these are quite different products - and choosing between them isn't just a matter of price. In this article, we'll take a detailed look at both brands: where their design philosophy differs, what that means in practice during everyday use, and how to decide which convector is right for you.
If you're still at the very beginning of your selection process and don't know what convector power output to even consider, we recommend first reading our article What power output of an electric convector do I need for my room - it will help you narrow down your choice before you start dealing with a specific brand.
Brief Profile of Both Brands
Protherm - a Slovak-European context, dominantly heating technology
Protherm is a brand most Slovaks know primarily from the field of gas boilers. Electric convectors are a relatively slim, but well thought-out product line in their portfolio, designed for simple, reliable operation without unnecessary complications. Protherm convectors are sold in specific power levels - 500, 1,000, 1,500 and 2,000 W - which covers the vast majority of common needs, from a small bathroom to a larger living room.
Protherm's philosophy in the convector segment is easy to read: robust construction, simple mechanical control, minimalist design, low failure rate. The target group are households that don't want to deal with smart functions or Wi-Fi, but need a reliable source of heat that they can switch on and forget about.
Tesy - a Bulgarian manufacturer with European ambitions
Tesy is a Bulgarian manufacturer that has grown over the past two decades into one of the largest European producers of electric heaters. Their range of convectors is significantly wider than Protherm's - starting from 500 W and reaching up to 3,000 W, and within individual power levels they offer several different series that differ in the type of control, design, accessories and additional features. Tesy relies on modern aesthetics, electronic control and various smart functions in its premium ranges.
If you're looking for a convector with a weekly programmer, LCD display, open window detection or Wi-Fi control, you'll most likely end up choosing Tesy. Their basic ranges are also very affordable and represent strong competition for the mid-range segment.
Construction and Heating Technology: Where the Real Differences Lie
Both manufacturers use the standard principle of natural convection: cold air enters through the bottom grille, passes over the heating element, warms up and rises through the outlet grille. In this respect, the convectors are similar. The difference lies in the type of heating element itself and the way temperature is regulated.
Heating Elements: Wire Resistance Elements vs. PTC Ceramics
In its basic convector line, Protherm uses classic wire resistance heating elements made of stainless steel. These elements are extremely durable, simple to manufacture and, if needed, easy to service. Their weakness is that the element itself doesn't have a self-limiting character - the temperature rises linearly with power input, so temperature regulation in the room is entirely in the hands of the thermostat.
Tesy, in some of its ranges (especially premium series), uses PTC (Positive Temperature Coefficient) ceramic heating elements. These have an interesting property: as the temperature rises, their electrical resistance increases, which naturally limits power input and prevents overheating. The result is slightly smoother and more even heating without significant temperature fluctuations. However, in the basic, cheaper Tesy ranges you'll also find classic resistance elements, so it's worth checking the technical data sheet when choosing a specific model.
Temperature Regulation: Where the Two Manufacturers Differ Most
Temperature regulation is probably the most important difference between the two brands in everyday practice. We cover this topic in more detail in the article Convector with electronic vs. mechanical control: which is better, but for the purpose of comparing the two brands, here's a summary.
Protherm: Mechanical Control - a Deliberate Choice, Not a Compromise
Protherm convectors, in all power variants - from Protherm 500 to Protherm 2000 - use a bimetallic mechanical thermostat with a rotary control. This thermostat has no digital display, won't show you the exact temperature in Celsius and doesn't allow setting a specific value in degrees. You set it on a scale from minimum to maximum (sometimes with marked Frost/Comfort symbols).
The accuracy of a bimetallic thermostat is typically ±2 to 3 °C, meaning that if you want 21 °C, the convector may operate in a range of 18-24 °C. For most uses - supplementary heating, garages, occasionally used rooms, storage - this accuracy is completely sufficient. Problems arise with long-term, daily use in living spaces, where people get used to the comfort of precise regulation and perceive temperature fluctuations negatively.
The advantage of mechanical control is an almost zero failure rate of the electronic part (because there isn't one) and resistance to fluctuations in supply voltage. From a technical standpoint, there's nothing outdated about this design choice - it's intentional, not a forgotten design update.
Tesy: Electronic Control with Varying Levels of Sophistication
Within its range, Tesy offers several different levels of control. The basic ranges have a simple electronic thermostat with LED indication, mid-range models have an LCD display with settings in degrees Celsius and an accuracy of ±0.5 °C, and premium ranges feature a weekly programmer, an open window detection function (when the sensor detects a rapid temperature drop, the convector automatically switches off, thus saving energy), adaptive heating, and in some cases even a Wi-Fi module for smartphone control.
Electronic control also brings an ECO mode function, where the convector maintains a lower temperature (typically 3-4 °C lower than the set comfort temperature) during pre-programmed hours - for example when you're not home or asleep. Over the long term, these functions can bring measurable energy savings compared to simple mechanical control.
Power Ranges and Room Coverage: Table Comparison
| Power | Protherm (model) | Tesy (approximate) | Recommended area* | Typical use |
|---|---|---|---|---|
| 500 W | Protherm 500 | Tesy 500 W | up to 6-8 m² | WC, hallway, bathroom |
| 1,000 W | Protherm 1000 | Tesy 1,000 W | 8-12 m² | Bedroom, small office |
| 1,500 W | Protherm 1500 | Tesy 1,500 W | 12-18 m² | Living room (supplementary), study |
| 2,000 W | Protherm 2000 | Tesy 2,000 W | 18-25 m² | Larger living room, workshop |
| 2,500 W | — | Tesy 2,500 W | 25-30 m² | Large living room |
| 3,000 W | — | Tesy 3,000 W | 30-38 m² | Commercial spaces, open-plan layouts |
*Approximate values for a well-insulated space with a ceiling height of 2.6 m. For older properties or rooms with larger glass surfaces, expect to need higher power output.
The table reveals one practically important point: Protherm covers the power range up to 2,000 W, which is sufficient for most households, but for larger spaces or when a convector is needed as the sole heat source in a larger room, the Tesy range is more advantageous due to higher power outputs. You can read more about calculating the required power output in the article What power output of an electric convector do I need for my room.
Design, Dimensions and Installation Options
One of the less discussed, but in practice important, areas is the physical dimensions of the convector and its installation options.
Protherm convectors typically have a lower and longer profile - meaning that at the same power output, they are wider and lower than Tesy units. This geometry has an advantage when installing under low windows, where the space between the floor and window sill is limited. The disadvantage is that they need more horizontal space on the wall.
Tesy ranges usually have a taller, more compact shape, which can be advantageous in narrower rooms or when installing on walls where there isn't enough width available. Some Tesy series are also available in a version with wheels, making them a mobile appliance - an ideal solution for spaces where wall mounting isn't suitable or possible.
If you're interested in the wheeled version, check out the set of wheels for Tesy - an accessory that turns a wall-mounted Tesy convector into a mobile heater that's easy to move around the room. You can learn more about this accessory in the article Wheels for an electric convector: when are they worth it and what to know.
Both manufacturers supply wall brackets and mounting materials with their convectors. The installation procedure is similar for both brands - the brackets are attached to the wall, and the convector is fitted and secured in place. You'll find a detailed guide in the article Mounting an electric convector on the wall: step-by-step procedure.
Energy Efficiency and Operating Cost Savings
It's important to dispel a common misconception right at the start: an electric convector has an efficiency close to 100%, regardless of whether it's a Protherm or Tesy brand. Electrical energy is converted into heat with almost no losses. Therefore, the heating element itself is not where you should look for savings - it's identical for both brands.
Where real savings are made is in regulation and operation management. And here Tesy has a measurable advantage thanks to more precise electronic control and programming function. Manufacturer studies and calculations show savings of 20-30% compared to constant operation with properly set program control. So if you're comparing operating costs over 5 or 10 years, the price difference between a mechanical Protherm and an electronic Tesy may disappear or even reverse in favor of Tesy.
Of course, this only applies if you actually use the programmable functions. If you set the convector to a certain temperature and let it run continuously without changes, electronic control will bring no additional savings over mechanical control.
Reliability, Lifespan and Service: What Practical Experience Shows
Based on experience from several years of sales and service cases, the following can be said:
Protherm convectors are among the devices with an extremely low failure rate. The mechanical construction of the thermostat, with no electronic components, means that in normal operation there is almost nothing that can go wrong. Most service cases involve physical damage - for example, a mechanically damaged grille or a burnt-out heating element due to long-term covering (which is a user error, not a product defect). The stainless steel heating element resists corrosive environments and retains its performance over the long term.
Tesy has a somewhat higher proportion of service cases related to the electronic regulator compared to Protherm - mainly in older models. The electronic display, buttons and, in the case of smart models, the Wi-Fi module represent components with a limited lifespan that can fail independently of the heating element. Tesy responds to this with improved electronics protection in newer series, and most models are covered by a 2-3 year warranty.
In case a repair is needed, it's important to know that spare parts for Tesy are relatively well available in Europe, and the service network is well developed. The same applies to Protherm - as it's an established brand with strong support in Central Europe.
You can read more about common malfunctions and their solutions in the article Common electric convector faults and how to fix them, and about extending lifespan in Maintenance and cleaning of an electric convector: how to extend its lifespan.
Price: Where the Real Price Differences Lie and What You Get for Them
The prices of convectors from both brands in the basic ranges are relatively close to each other. In the 1,000 W category, they typically range from 50-90 EUR, with the basic Tesy ranges and Protherm convectors being in a similar price band. A more significant price spread occurs at the higher end: premium programmable Tesy ranges with Wi-Fi can cost 150-250 EUR per unit, a category in which Protherm simply isn't present.
For a customer looking for just a basic convector for a cottage or garage, the price difference between Protherm and the basic Tesy range is minimal. When equipping an entire apartment with electronically controlled convectors, choosing a premium Tesy may represent a significant investment, which, however, with proper use of the programming functions, is justified in the long run by a lower electricity bill.
Practical Scenarios: When to Choose Which
Scenario 1: Cottage, Occasional Heating, No Permanent Electric Heating
A cottage owner who arrives for the weekend and needs to quickly warm up a room or bathroom will appreciate a Protherm convector. Why? It doesn't require any setup, programming or learning. You arrive, turn the knob, the room warms up. Mechanical control is resistant to longer pauses in operation (the cottage stands empty for months) and isn't bothered by freezing temperatures during storage. For basic needs - for example, heating 10 m² within 2 hours - the Protherm 1000 is a reliable and cost-optimal choice.
Scenario 2: New Build, Electric Heating as the Main Heat Source
An investor who has decided on electric heating in a new build with good thermal insulation should seriously consider a Tesy with a weekly programmer. In this case, the convector will be operating 24/7, all week, 6 months a year. The difference between programmed ECO mode (for example, 18 °C during absence and 21 °C when present) and unprogrammed constant operation can amount to hundreds of euros a year in electricity costs when heating an entire apartment. Tesy with a programmer is the clear choice here. You'll find more on this topic - including cost calculations - in the article Electric convector as a main vs. supplementary heating source.
Scenario 3: Adding a Bathroom or WC to Central Heating
A homeowner with a gas boiler who wants to add an electric convector as a supplementary heat source in the bathroom (for example, for morning and evening hours) has a fairly free choice. Both brands can handle this task. If the bathroom doesn't have a moisture problem and the convector will only be supplementary, the mechanical Protherm 500 is sufficient and inexpensive. If you want automated operation - for example, so the bathroom is warm before a morning shower - Tesy with a programmer wins again.
Scenario 4: Renovating a Single Room, Mobility, No Drilling
A tenant or owner who doesn't want to drill into the wall, or needs a heater that can be moved between rooms (for example, a workshop + living room), should opt for a Tesy fitted with a set of wheels. The wheels are mounted to the bottom of the convector and allow easy movement. Protherm doesn't typically offer similar accessories.
Warranty Conditions and Service Availability
Protherm provides a 2-year warranty period on electric convectors, service is provided through authorized partners, and in the event of a heating element failure, replacement is straightforward. Tesy standardly provides the same 2-year warranty period, with some premium series offering an extended warranty of up to 5 years after registering the product on the manufacturer's website - an interesting bonus for a convector as a long-term appliance.
The availability of spare parts is good on the Slovak market for both brands - replacement heating elements, regulators and mechanical thermostats are available through distributors and service partners with a usual delivery time of 3-10 business days.
Summary: Where Each Brand Excels and Who It's Suited For
Protherm electric convectors are ideal for customers who:
- are looking for simplicity and maximum reliability without electronic components,
- heat occasionally used spaces (cottages, garages, storage rooms, guest rooms),
- don't need precise temperature settings in degrees or programming,
- want a low entry price without compromising on material quality,
- are installing the convector in spaces with limited height under the window sill (lower profile).
Tesy electric convectors are ideal for customers who:
- heat continuously with a convector or use it as a primary heat source,
- want precise temperature control, programming or smart functions,
- need power outputs above 2,000 W,
- are considering a mobile solution with wheels,
- want a modern design with a display and advanced features such as open window detection.
Frequently Asked Questions (FAQ)
Is a Protherm convector suitable for a bathroom?
It depends on the specific model and its protection rating (IP rating). Standard Protherm convectors without special protection are designed for dry spaces. For a bathroom, you need to verify that the specific model meets the requirements for the given safety zones (typically IP24 or higher). Tesy has models in its portfolio specifically designed for bathrooms with appropriate IP protection - so when choosing for a bathroom, Tesy offers a wider selection of safely certified options.
Can I connect a Protherm or Tesy convector to a smart home?
Basic Protherm ranges are not compatible with smart home systems - they have no communication protocol. Some Tesy ranges are equipped with a Wi-Fi module and support app control. If you want smart home integration, look for specific Tesy models with Wi-Fi or Bluetooth functionality and verify compatibility with your system (Tuya, Google Home, Amazon Alexa).
Which manufacturer is more economical to run?
In terms of the conversion of electricity into heat itself, both brands are equally efficient (close to 100% efficiency). Tesy achieves savings thanks to more precise control and programming - but only if you actively use these functions. If you simply switch the convector on and let it run without programming, the cost difference will be minimal.
Can I use Tesy wheels on a Protherm convector?
No. The set of wheels for Tesy is designed for the specific dimensions and mounting points of Tesy convectors and is not compatible with Protherm. Protherm typically doesn't offer wheels as an accessory, and its convectors are primarily designed for fixed wall installation.
What's the difference in noise level between Protherm and Tesy?
Both convectors operate without a fan (natural convection), which means that noise levels are minimal for both during normal operation. During heating start-up, you may hear slight cracking with both brands due to thermal expansion of the metal parts - this is a normal phenomenon and not a fault. With Tesy's electronic control, you may hear a quiet clicking of the relay, but this is negligible and you'll get used to it over time.
Which side offers better warranty service?
For the Slovak market, warranty service for both brands is at a comparable level. Protherm has the advantage of a strong local presence and an extensive service network (primarily for boilers, but the same partners also service convectors). Tesy has a pan-European service network, and some premium series offer an extended 5-year warranty after registration. If a long warranty is decisive for you, ask about the possibility of an extended warranty for the specific Tesy model when purchasing.
Conclusion
Protherm and Tesy are two different answers to two different sets of needs. Protherm excels where you want trouble-free, long-term reliable operation without worrying about settings and electronics. Tesy is stronger where you need precision, programming comfort, and possibly smart functions. Prices in the basic ranges are comparable, while in premium ranges Tesy offers significant added value - but also a higher entry price.
If you're still not sure which model is right for you, we also recommend reading our comprehensive guide How to choose an electric convector: power, control and other criteria, or check out Frequently asked questions about electric convectors, where you'll find answers to further practical questions. You can find the entire range of both brands, including current prices, in the electric convectors category.
Do you have a question on this topic?
Can't decide or dealing with a specific situation in your household? Write to us - we're happy to help.