Viessmann Vitodens 100-W 35kW B1KF Combi Boiler | 7098714

Description

The Viessmann Vitodens 100-W is the flagship wall-mounted gas condensing boiler in the Vitodens range, pairing the MatriX-Plus gas burner with intelligent Lambda Pro combustion control and the corrosion-resistant Inox-Radial stainless steel heat exchanger.

This 35kW combi variant delivers instantaneous hot water on demand alongside central heating, making it a strong fit for larger households needing higher simultaneous hot water flow without a separate cylinder.

35kW

Combi output

94%

Seasonal efficiency (ηS)

17.04 l/min

DHW flow rate

Class A

Energy efficiency

360mm

Depth

WiFi

Built-in connectivity

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Please Note: This boiler must be connected using the Viessmann 60/100mm concentric flue system, tested and CE-designated as one structural unit with the boiler in accordance with DVGW-VP 113. Only this flue system may be used, with maximum flue lengths varying by model — check the installation manual for the exact figure.

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Good to Know: This boiler is approved for a hydrogen admixture of up to 20% by volume and can be configured for LPG entirely from the control unit — no separate conversion kit is required.

MatriX-Plus burner with Lambda Pro

Delivers extremely clean combustion and quiet operation, with automatic combustion control across the full modulation range.

High DHW flow rate

Delivers up to 17.04 l/min at a 30K temperature rise, suiting higher simultaneous hot water demand.

Inox-Radial stainless steel heat exchanger

Provides high operational reliability and a long service life on a compact footprint.

Variable speed high efficiency circulation pump

Cuts pump power consumption by up to 70% compared with a fixed-speed equivalent.

Integral WiFi with local app access

Supports the ViCare app for remote control, plus local commissioning access without an active internet connection.

Touchscreen control unit

Easy day-to-day operation via a backlit LCD touchscreen display.

Specification

Performance

Boiler type

Gas condensing combi (Type B1KF-35)

Rated heat output (50/30°C)

3.2 – 32.0 kW

Rated heat output (80/60°C)

2.9 – 29.3 kW

Continuous DHW output

34.4 kW

DHW flow rate (ΔT 30K)

17.04 l/min

Standard seasonal efficiency (Hs)

Up to 98%

Seasonal central heating efficiency (ηS)

94%

Energy efficiency class

A

Sound power level (rated output)

50.4 dB(A)

Gas & Electrical

Gas types

Natural gas and LPG (configured at control unit)

Hydrogen compatibility

Up to 20% H2 blend

Natural gas supply pressure

20 mbar

LPG supply pressure

50 mbar

Electrical supply

230V~, 50Hz

Power consumption (delivered condition)

110W

Dimensions & Connections

Height

700mm

Width

400mm

Depth

360mm

Weight (excl. water)

35kg

Flue gas connection

60mm

Ventilation air connection

100mm

Boiler flow and return

R 3/4"

Cold water and DHW connections

G 1/2"

Expansion Vessel

Capacity

8 litres

Pre-charge pressure

0.75 bar

Max. permissible operating pressure

3 bar

What size property suits the 35kW Vitodens 100-W combi?

A 35kW combi is typically suited to larger 4-5 bedroom homes or properties with higher simultaneous hot water demand — a heat loss calculation confirms exact sizing.

Does this boiler require a mounting jig?

Yes, a pre-plumbing jig or valves/fittings pack for surface or flush mounting must be ordered separately.

How does the DHW output compare to the Vitodens 050-W 35kW combi?

Both deliver a similar continuous DHW output around 34-35kW, but the Vitodens 100-W offers a slightly higher DHW flow rate and wider modulation range.

Is a WiFi modem needed for the ViCare app?

No, WiFi connectivity is integral to the control unit on this model.

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Room Dimensions

Length (in m):

Width (in m):

Height (in m):

Room Type

Living Room

Bedroom

Kitchen

Bathroom

Conservatory

Hallway

Glazing Type

Single Glazed

Double Glazed

Triple Glazed

External Walls

0 Wall

1 Wall

2 Walls

3 Walls

4 Walls

Insulation Level

Poor

Average

Good (New Build)

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Required Heating

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Watts

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