Viessmann Vitodens 100-W Combi Boiler

Why Choose the Viessmann Vitodens 100-W Combi Boiler?

If you’re considering the Viessmann Vitodens 100-W combi boiler, it’s absolutely one of the top-rated and bestselling options in the UK as of December 2025. 

This model consistently ranks highly in independent reviews and frequently earns Which? Best Buy awards for its outstanding reliability, performance, and overall value.

Key Features and German Engineering

This is Viessmann’s mid-range powerhouse, showcasing pure German engineering at its finest. It features a highly durable stainless steel Inox-Radial heat exchanger with brass and copper internals for exceptional toughness and corrosion resistance, ensuring long-term performance even in varying water conditions.

Operation is whisper-quiet thanks to an advanced fan design, and it achieves up to 94% efficiency, translating to noticeable savings on energy bills. The boiler is compact for easy installation, hydrogen-blend ready (up to 20%) for future-proofing against greener fuels, and comes with a user-friendly backlit LCD touchscreen for intuitive control.

Smart Controls and Connectivity

One standout feature is the built-in WiFi, allowing seamless integration with the ViCare app. This enables remote scheduling, real-time monitoring, energy usage insights, and even remote diagnostics—perfect for busy households or when you’re away from home. Pair it with Viessmann’s smart thermostat for even greater control and efficiency gains.

Reliability, Warranty, and User Feedback

Homeowners and installers alike praise the Vitodens 100-W for its consistent hot water delivery, low running costs, and impressive longevity—many units last 15+ years with proper maintenance and annual servicing. It offers a market-leading warranty of up to 12 years when installed by a Viessmann-accredited engineer and paired with a system filter, providing excellent peace of mind.

Is the Viessmann Vitodens 100-W Right for You? A Balanced Review

My unique perspective after comparing numerous boilers: The Vitodens 100-W strikes an ideal balance—premium quality and features without the ultra-high price tag of top-tier models. It costs more than the entry-level Vitodens 050-W but justifies it with built-in WiFi, superior hot water flow rates, and that extended warranty, making it better long-term value for most users.

If your household has very high hot water demand (e.g., multiple bathrooms in constant use), you might want to look at the Vitodens 111-W with integrated storage for even faster recovery. But for the majority of small to medium UK homes, this model perfectly blends cutting-edge efficiency, smart technology, and rock-solid German reliability.

Final Recommendation

Overall, if you’re seeking a high-end combi boiler that delivers on performance, smart features, and durability without excessive cost, the Viessmann Vitodens 100-W is a standout choice in 2025. It’s ideal for homeowners prioritising quality engineering and future-ready tech. With its impressive energy efficiency and innovative design, the Vitodens 100-W consistently ranks among the best combi boilers for your home. Additionally, its user-friendly interface and remote control options enhance convenience, making it easier to manage your heating needs. Homeowners can enjoy peace of mind knowing they are investing in a reliable system that can adapt to future technological advancements.

Specs Table for the Vitodens 100-W

Outputs: 26kW, 30kW, 35kW—the 30kW suits most.

Specification	26kW Model	30kW Model	35kW Model
Central Heating Output	Up to 26kW	Up to 30kW	Up to 35kW
Hot Water Flow Rate	~11-12 l/min (35°C rise)	~12-14 l/min	~14-16 l/min
Energy Efficiency	ErP A-rated (94%)	ErP A-rated (94%)	ErP A-rated (94%)
Dimensions (H x W x D)	700 x 400 x ~350mm	Same	Same
Weight	~35-38kg	~38kg	~38kg
Noise	Whisper-quiet	Whisper-quiet	Whisper-quiet
Key Features	Stainless exchanger, built-in WiFi, ViCare app, touchscreen	Same	Same, higher output
Warranty	Up to 12 years (accredited + filter)	Up to 12 years	Up to 12 years
Best For	Smaller homes, 1 bath	Medium, 1-2 baths	Higher demand

What’s your home like—bathrooms, radiators, or WiFi/smart setup? I can help decide if the 100-W (and which size) is your best upgrade!

 

How Does the Vitodens 100-W Compare to the 050-W and 200-W?

Viessmann tiers:

• 050-W – Entry-level (excellent value, essentials)
• 100-W – Mid-range bestseller (smart features, premium build)
• 200-W – Flagship (ultimate modulation, advanced tech)

Side-by-side (combi models, late 2025):

Feature	Vitodens 050-W	Vitodens 100-W	Vitodens 200-W
Range Positioning	Entry-level/value	Mid-range/most popular	Premium/flagship
Best For	Small-medium homes, budget quality	Medium homes, smart & reliable	Larger homes, max performance
Hot Water Flow Rate	~12 l/min	~12-14 l/min	Up to 18-20 l/min
Efficiency	94% ErP A-rated	94% ErP A-rated	94% (superior modulation)
Noise Level	Very quiet	Whisper-quiet	Super quiet
Dimensions	Ultra-compact	Compact cupboard fit	Slightly larger
Design & Controls	Basic touchscreen	Backlit LCD touchscreen, built-in WiFi	Premium touch, advanced
Key Features	Stainless exchanger	ViCare app, easier service	Lambda Pro, top diagnostics
Warranty (accredited)	Up to 10 years	Up to 12 years	Up to 12 years
Relative Price	Cheapest	Mid	Most expensive

 

The 100-W is ideal for most—premium durability and smarts over the 050-W, without needing the 200-W’s extras.