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Viessmann Vitodens 100-W Heat Only B1GA 25 kW - 7959997

SKU 7959997
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A compact and efficient heat-only gas boiler

A heat-only, wall-mounted gas-fired condensing boiler which is compact enough to fit in a standard kitchen cupboard. Also suitable for use in other applications with limited space available.

  • Rated outputs: 11 kW, 16 kW, 19 kW, 25 kW and 32 kW
  • Compact dimensions to fit in standard kitchen cupboards
  • ERP efficiency 93% (Class A)
  • Weather compensation option large user display
  • 5-year comprehensive warranty as standard
  • Viessmann Trained Installers can now offer their customers an extended warranty option up to 12 years

Key Benefits
Efficient, durable, quiet
The corrosion-resistant stainless steel Inox-Radial heat exchanger with unrivalled wall thickness is extremely durable and achieves efficiency levels of up to 93%.

The boiler's special design ensures a very low operating noise of 39 dB(A) maximum (26 kW), which is perfectly acceptable even in the kitchen.

Inox radial burner
Weather compensation
Intelligent weather compensation
The Vitodens 100-W Open vent can even operate in weather compensated mode without incurring a costly heating system modification, all that is needed is a simple upgrade.

Weather compensation acts like an auto-pilot as it detects outside temperature changes and automatically adjusts the flow temperature of the boiler, achieving gas savings of up to 12% in the process.

Compact dimensions
With a depth of only 285 mm (340 mm on the 32 kW model) the compact Vitodens 100-W Open vent boiler is perfectly suited for integration into standard kitchen cupboards.

It can also be used in a vast number of other applications where there is only limited space available.

Versatile system solutions
Whilst being specifically designed for open vent heating systems, the Vitodens 100-W heat only is suitable for sealed systems using an additional expansion vessel safety valve.

Product details

  • Output in kW - 11 to 32 kW
  • Standard seasonal efficiency [to DIN] - 98 % (Hs) [gross cv]
  • Energy efficiency class - A
  • Fuel - Natural gas, LPG, 20 % hydrogen mixture
  • Application area - Detached/terraced houses, apartments, for new build and modernisation projects
  • Additional features - MatriX-Plus burner with Lambda Pro combustion controller for permanently high efficiency and clean combustion. Certified for 20 % hydrogen content in natural gas.

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