Company profile

  • Vogel Flug ltd., a 100% European company, has been at the forefront of European water heater industry Eatablished in 2016 in downtown Europe, we have now expanded our office and manufacturing facilities of over 10,000 square meters to the current location in worldwide. International water heater products, from residential to commercial and industrial markets. Our production is equipped with a of-the-art manufacturing technologies to ensure highest quality products to suit the customer's needs.
  • With the management's vision and strong dedication to develop world-class standard products, Isto. has been offering high efficiency, low energy consumption and eco-friendly water heater systems under the "Isto" brand. Together with reasonable prices and prompt delivery time, we are confident that you will receive the highest quality products and best service experience from us.



  • Be the Leader of manufacturers for Water heating.


Core Values

  • Cost Conscious
  • Customer Satisfaction
  • Commitment
  • Competence


A brief History of the company

  • STO brand and the same-name company ISTO d.o.o. was established in Croatia in 2016 in cooperation with Vogel flug (Austria) as a separate brand specialized in the manufacturing, sale and maintenance of water heating equipment. "ISTO", which is translated as "THE SAME", is intended to prove that the water heater is not a luxury, and impeccable quality is not necessarily costly for a buyer. On this basis, the company slogan was formulated as "WHY PAY MORE, BUY ISTO (the same)." Also, ISTO name is an abbreviation of major advantages of products provided to the buyer, i.e. Innovation Safety Tank for Ourself.

    ISTO engineers and marketers have been working hard for a long time to provide the buyer with products meeting the requirements of reliability, efficiency, good performance and low cost. In 2016, the first line of water heaters, which proved that a good water heater does not have to be expensive, was introduced to the market. Still, the products are superior in performance to their more expensive counterparts in the market due to a greater thermal insulation (saving electricity during operation), a greater steel thickness of the inner water heater tank and, accordingly, a longer warranty term and lifecycle.

    The company does not stop there and continued to move beyond. In 2017 it presented a new line of water heaters with a more attractive design and a more extensive product range. The current product range comprises the water heaters with 355, 445, and 475 m diameters, square and flat models, with both wet and dry heating element and a capacitance of 5 to 200 liters in vertical and horizontal design. The product line is supplemented with products allowing to heat water from alternative heat sources, such as solar energy, boiler and other sources of warm water due to models with an integrated coil-shaped heat exchanger or "tank-in-tank" design.

    The production facilities are located in Croatia within the company with a long history: KONČAR - KUĆANSKI APARATI d.o.o.
    KONČAR - KUĆANSKI APARATI d.o.o. was founded by KONČAR - Štednjaci d.o.o. and KONČAR - Mali kućanski aparati d.o.o. at the end of 1998. The company’s headquarter is located at Slavonska avenija 16, Zagreb.

  • КKONČAR – the furnaces are manufactured by GORAN plant producing furnaces for solid fuel and equipment for public catering as a part of its core program.
    GORAN plant joined the KONTAKT plant in 1963. Then they started manufacturing oil heaters and stoves, electric cookers and washing machines in collaboration with AEG, a German company. During this period, about 150,000 pieces of equipment were manufactured every year.

    КKONČAR - Small home appliances, headquartered in Samobor based on ELEKTRON plant producing electric water heaters, irons, vacuum cleaners, heaters, bread ovens, and other products. ELEKTRON joined the KONTAKT plant in 1963. The current production of household appliances has been growing and updating, extending to the kitchen fryers and steam irons in collaboration with AEG. During this period, the production has increased to more than 400,000 pieces a year.
    KONTAKT manufacturing facilities, producing household appliances, joined RADE KONČAR in 1970. After that, both of these plants introduced the extensive production of household appliances based on its own developments, especially in terms of small household appliances and manufacturing of electric heaters. Due to cooperation and acquisition of tools and equipment, the manufacturing of electric, induction and gas cookers, modern washing machines, as well as upgrade of small home appliances and water treatment plants using polymer materials of own design and processing was started.

    In late 2004, the company established: KONČAR - Trgovina i zastupstva d.d. and KONČAR - Servis i prodaja d.d.
    After this merger, KONČAR - KUĆANSKI APARATI d.o.o., in addition to being involved in its own home appliances manufacturing under Končar brand and export of appliances as its core business, is also engaged in provision of services, sale of household appliances of own production, as well as third-party appliances. Also, KONČAR - KUĆANSKI APARATI d.o.o. provides warranty maintenance of own devices and household appliances, as well as third-party equipment sold in Croatia.



Air-Conditioning and water Heater Experts

  • Vogel Flug ltd. is involved in full-cycle water heaters business, from product design and development, to production and installation for a wide variety of applications. We are continuously staying at the cutting edge of technology development and production to ensure that our water heater display the highest quality and meet the most stringent demands of international standarts.
  • With long experience and expertise in water heating engineering, we can design and manufacture systems water heating to meet customers' specific requirements. We adopt the state-of-the-art production technicians; together with rigorous inspection and quality control steps to ensure that only the highest-quality products are delivered to our customers.




    With long experience and expertise in water heater engineering, we can design and manufacture water heating systems to customers’ specific requirements.



    Production & Quality Assurance

    Production stays abreast of techno-logical development in order to achieve, maintain and improve the quality and standards of products and designs. The Production Department has a wide variety of responsibilities, ranging from producing parts, components and coil boards to the processes of cutting, folding and body spraying.



    Export Standards

    Vogel Flug ltd. has succeeded in all continents, with water heating systems operable in different climate from very cold climate in Canada and Russia to very warm cilmate in the Middle East and widely ranging climate in Australia. We have exported to more than 70 countries worldwide, both under "Isto" brand and as OEM suppliers.