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Viessmann Vitodens 100-W Boiler Review: Should you buy it?

Your friends won't be impressed that you've bought a Viessmann but you will. Why? You ask. Read our incredibly short Viessmann Vitodens 100-W review to find out. It's gold.

Your friends won't be impressed that you've bought a Viessmann Vitodens 100-W, but you will.

The Which? Best Buy award is usually reserved for the Worcester-Bosch and Vaillant's of the world, much like the Ballon d'or is seemingly reserved for Messi and Ronaldo but an unlikely German has got a look in this time around. In the boiler world, at least.

What's more, Viessmann boilers took the #2 spot in our list for the best combi boiler to buy in 2021. Result.

Got your heart set on a Viessmann Vitodens 100? Get a fixed online price today, and new boiler replacement tomorrow.

Introducing the Viessmann Vitodens 100-W review...

Viessmann Vitodens 100-W Review

Viessmann Vitodens 100-W Review

In this Viessmann Vitodens review, we've scored the 100-W in 4 key areas, including: 

  • Reliability: 5 Stars ⭐⭐⭐⭐⭐
  • Performance: 5 Stars ⭐⭐⭐⭐⭐
  • Warranty: 5 Stars ⭐⭐⭐⭐⭐
  • Price: 4 Stars ⭐⭐⭐⭐

The Viessmann is a gas-fired combination boiler that is designed to be wall-mounted. Available in multiple different power outputs it is suitable for a wide range of homes and its compact size makes it ideal for properties with limited space.

The features offered with the Vitodens 100-W rival a good deal of combi boilers on the market right now, if not all of them. This is especially true with the updated 2021 model.

Main features of the Viessmann Vitodens 100-W Boiler: 

Before we get into the details, here are some of the most notable features of the Viessmann Vitodens 100-W model (most recent 2021 model)

  • Class 'A' for energy efficiency
  • 10-year comprehensive warranty as standard - when purchased with Heatable
  • 89.5% efficiency
  • Hydrogen-ready for the next generation of fuel 
  • Weather compensation option for Boiler Plus compliance
  • Backlit LCD touchscreen display 
  • Stainless steel heat exchanger 
  • Compatibility with the Viessmann Vitronic smart thermostat - that sounds fancy

Looking for a groundbreaking and STILL award-winning Viessmann boiler on a budget?! Check out the Viessmann Vitodens 050-W 29kW.


Want an exact price on a new boiler? Use our boiler quote calculator (your fixed price will appear on screen).

Reliability: 5/5 ⭐⭐⭐⭐⭐

The Viessmann Vitodens 100-W is the best selling combi boiler from the award winning brand and has an impeccable reputation. 

Trustpilot Reviews 

For illustration, on TrustPilot, Viessmann UK has racked up an incredible amount of reviews. As of April 2021, over 1,000 customers left a review.

The brand has an average rating of 4.5 stars out of 5, incredible for a company that's still relatively new to the UK market. 

Moreover, in our article ranking the best boiler manufacturers, the brand stole the number 2 position as the best combi boilers of 2021;  so, this is certainly a boiler brand with credibility.


If you are questioning whether to choose between Viessmann and Worcester check out our recent comparison between the two boiler makes. 

Which? Boiler Survey Results 

Viessmann was previously awarded the Which? Best Buy Award from 2017 to 2020 and since their introduction to the UK market has made continued efforts to improve the availability of spare parts. 

Performance: 5/5 ⭐⭐⭐⭐⭐

Viessmann Vitodens Combi Boiler Power Outputs 

The Viessmann Vitodens 100 combi boiler range is available in the following sizes (power outputs):

  • 26kW
  • 30kW
  • 35kW

The 30kW combi boiler (most popular) has a heat output of 30kW and a flow rate of 12.3 l/min, making it suitable for average sized properties that may have slightly greater hot water demands. 

The 100-W range is also available in various other power outputs with corresponding flow rates, ideal for properties with greater hot water demands. 

The hot water flow rates range from 10.6 l/min up to 14.3 l/min, offering excellent pressure and capacity for any households that have a significant hot water demand. 

Want to know which boiler power is right for your home? Check out our boiler sizing guide.

You can check the latest deals on Viessmann boilers here, and see how the brand compared to another market leader in our Worcester Bosch vs Vaillant Boilers comparison.  

Efficiency of the Vitodens 100-W

The Viessmann Vitodens 100-W is certified as A-rated for efficiency and offers 89.9% efficiency.

You can save even more energy and money by controlling the boiler with a smart thermostat. 

This allows you to control your boiler from a convenient smartphone app, allowing you to set up schedules and gain access to a whole range of other energy-saving features. 

The Vitodens 100 dimensions - size does matter

Viessmann Vitodens 100-WThe Viessmann Vitodens 100-W comes in a pretty compact size for a wall mounted combi boiler (see dimensions below). Its compact size will allow for fitting in most standard kitchen cupboards and not make it too much of an eyesore when fitted externally in a living space.

Live in a cupboard in London? No problem.

Dimension (mm)
Height 700
Width 400
Depth 350
Not just small - it's quiet too! The Viessmann Vitodens 100-W is the preferred boiler of 78% of monastery confined monks
Sold on this heavenly white box? Get a fixed online price today, and installation tomorrow.

Controls & Features of the Viessmann Vitodens 100-W

A unique and standout feature of the latest Vitodens 100 is the Lambda Pro technology, which was previously only available in the 200 range. This ensures the gas valve constantly adjusts to the air and gas mix it receives, making sure it maintains maximum efficiency and burn rate. 

The latest Vitodens 100 also includes an updated LCD touchscreen display with integrated Wi-fi, allowing you to control, diagnose the boiler and enable remote access to Viessmann support so that they can assist from afar and diagnose faults. 

The touchscreen display also expands on the usual error code system and actually shows you which components have failed and may be causing the fault. This helps to alleviate the costs associated with diagnosing faults using a generic and broad error code. 

Warranty: 5/5 ⭐⭐⭐⭐⭐

The warranty is a major part of buying any new boiler as if something goes wrong you want the reassurance that it will be repaired and back in working order as soon as possible. 

The great news is that when you purchase your Viessmann boiler with Heatable, you will receive a 10-year warranty. 

Price Point: 4/5 ⭐⭐⭐⭐

Viessmann Vitodens Combi Boiler Costs

It's an award-winning boiler, from a world-leading brand with the latest features. That means it comes with a premium price tag. 

The exact costs of the boiler (including Gas Safe installation) may vary depending on your type of property, hot water demands and a whole host of other facts.


So, to make it easy, we have designed a quick questionnaire that will give you an instant fixed price. It takes about 60 seconds to complete.

Viessmann Vitodens 100-W Deals

However, for illustrative purposes Viessmann boilers through Heatable start from just £1,795 - considerably below the national UK average that breaks the £2,000 mark.

The Viessmann Vitodens 050 is their entry-level model, and prices start from just £1,795. The 100-W has had a recent price drop, and you can now bag one from just £2,295 (with a massive 10-year warranty).

Learn all about combi boilers in our what is a combi boiler guide. 

Viessmann Model Our Price   
Vitodens 050-W 29kW £1,795
Vitodens 050-W 35kW £1,995
Vitodens 100-W 26kW £2,247
Vitodens 100-W 30kW £2,295
Vitodens 100-W 35kW £2,530
Vitodens 200-W 35kW £2,750
Vitodens 111-W 26kW £3,180
Vitodens 111-W 35kW £3,421

Vitodens 100-W Which? Best Buy Boiler Review

Having claimed themselves a Which? Best Buy award, the Viessmann Vitodens 100-W (and its feisty little brother the Vitodens 050-W) offer oustanding value for money against their rivals, especially when considering their superior internal components for a longer lasting boiler.

Below is how Viessmann measure up for price against Which? Best Buy regulars.

Boiler Make Avg Price Price vs UK Avg
Worcester Bosch £2,189 + 5%
Vaillant £2,024 + 2%
Viessmann £1,990 - 4%
100-W. But what does the W stand for? We don't know. We're not sure anybody knows. Scholars maintain it was lost in translation hundreds of years ago.

Our Viessmann Vitodens 100-W Verdict

Viessmann Vitodens 100-W Review FeaturesThe Viessmann Vitodens 100-W review won't fight for your attention. He's no show off. He'll blend into the background, quietly confident that if you get to know him, he'll prove himself - and he will.

It's true, it's not as popular as a Worcester Bosch boiler even in spite of its components being made of spag bol, or as good looking as an Ideal Vogue but the Vitodens is a solid companion, a boiler with a good heart.

He's the type of boiler that'll pick you up from the airport at anti-social hours, give change to the homeless and put misplaced bird eggs back in their nest. The Viessmann Vitodens 100-W is loyal and dead set on saving you money, like a Labrador doing your accounts.

So with stats to topple the competition and a price point to better them, our answer would be - why on earth wouldn't you?

Get your fixed Viessmann price and book your installation now.

Read our Worcester Bosch vs Viessmann Boilers review if you want a quick comparison of these two trusted boiler manufacturers. 

Viessmann Vitodens 100-W Review Conclusion 

How do I get the best price on a Viessmann Vitodens 100-W?

How...? Without boasting, buy from us.

Use this clickable form to get a fixed price on the screen instantly. 

Why choose Heatable? 

  • Gas Safe installation within 24 hours.
  • Thousands of happy customers – an average score of 4.9 on Trustpilot (that’s better than the market leader). 
  • Price match guarantee – if you find a cheaper quote, we will match (must be like for like).  
  • Multiple payment options - interest free available. 
  • 10 year guarantee. 
  • Fixed price guarantee – no hidden costs. 
  • Save your quote until later. 

Fixed Online Boiler PricesBecause we're online, our overheads are low which means we pass those savings on to our customers, ensuring they're always getting the best deal on a new boiler. Plus, because of the volumes that we install, we're able to access exclusive warranty lengths from our partner manufacturers.

To get the best deal on a new Viessmann Vitodens 100, answer some quick online questions and we'll give you an instant fixed price and installation within 24 hours.


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[1] Price based on a like for like combi swap in a 2 bed, 1 bathroom terraced home with a standard flue

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