Vaillant Boilers
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Vaillant combination boilers for home and domestic water heating.

German-made Vaillant boilers are intelligent water heaters that are providing efficient and reliable home heating and hot water preparation. Vaillant combination boilers, also known as combi boilers are among the top European brands for hot water production.

Vaillant Group is one of the world's leading boiler manufacturers who also designs and makes HVAC products such as air conditioners, solar panels, HVAC controls and more. This brand is present in more than 75 countries making it a global brand.

Vaillant successful story started in 1894 with the construction of the first gas bath boiler and 1905 when the wall-hung water heater was invented for home use. For the last 125-year long history there are over 40 million units sold worldwide.

Today Vaillant Group manufacturers not only gas boilers (water heaters) for hot water production and home heating, but electric heat pumps, oil-fired condensing boilers; solar panels and geothermal equipment to utilize the free energy from "Mother Nature."

Types and features

There are three groups of Vaillant boilers for on-demand (tankless) water heating and a group of Vaillant cylinders:

  • High-efficiency combi boilers
  • System boilers
  • Open vent boilers
  • Cylinders

High-efficiency combi boilers

Vaillant combi boilers are actually tankless water heaters (as known in the US) that are the most popular and selling type of all Vaillant boilers. Vaillant combination boilers are high-efficient units that are working on demand, to heat home and domestic water, and they do not need a separate water storage tank.

Combi boilers are gas-powered that are providing hot water whenever hot water tap is open while the modulating gas burner through the intelligent electronics adjusts its power to meet the demand for central heating.

The most popular high-efficiency combination boilers are Vaillant ecoTEC exclusive, Vaillant ecoTEC plus and Vaillant ecoTEC pro, all of the wall-mounted, with room-sealed combustion and fan-assisted, offering different capacity. The most popular boiler sizes are 24 and 28 kW.

System boilers

System boilers, known as sealed system boilers require a storage cylinder to provide central heating and hot water. When they work with the unvented hot water cylinder, they do not require a cold water storage tank. The ecoTEC plus model represent system boilers.

Open vent boilers

Open vent boilers, usually have two tanks and hot water storage so they can provide central heating and hot water. They can also be used with the sealed boiler.

The last two systems are designed to deliver high volumes of hot water and for multiple outlets.

From 2005 it is a law in the UK that all combi boilers should be high efficiency or condensing boilers. These high-efficient boilers are using the flue heat for additional water heating, which results in increasing the energy efficiency to over 90%, making them more efficient than conventional boilers.


Vaillant also offers a great selection of the unvented stainless steel cylinders, uniSTOR series, which can provide a sufficient quantity of hot water for homes with one bathroom to households with multiple baths.

The available cylinder capacities range from 125 liters to 310 liters, and there are six of them. UniSTOR cylinders are equipped with the high recovery heating coil, and they are compatible with the Vaillant system boilers and boilers from other manufacturers.

Vaillant solar boilers

Vaillant started production of solar panels in 2008, and now it offers various types of auroTHERM collectors, auroTHERM solar cylinders, and auroTHERM solar controls:

  • Vaillant auroTHERM - flat plate solar collector 
  • auroTHERM Exclusive - vacuum tube solar collector
  • auroTHERM PLUS - anti-reflex flat plate collector

Superior features

  • State-of-the-art electronics with programming that shows the operating status and diagnostics.
  • Fully modulating low NOx burner with a fan.
  • Frost protection.
  • Special flow sensor for the constant hot water temperature.
  • Wireless programmable thermostat.
  • Attractive and modern design.
  • SEDBUK Band 'A' rated.

One of the greatest features this company offers for its boilers is the Vaillant Intelligent Service, which allows remote control of the water heater and heating system via the Internet and the adjustments according to your needs. If there is a problem with your Vaillant combi boiler you and the technical support will get the message, and they will check where the error is.


Vaillant boilers are the leader in water heating industry in Germany, UK... worldwide, and they offer an efficient and reliable solution for your home and most demanding applications. Based on your hot water needs you can buy one of many combi boilers this German manufacturer offers, either powered by natural gas, LPG, oil, electricity or solar.

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