Viessmann Vitodens 100-W Boiler Review

Viessmann Vitodens 100-W

The ultimate review of the fantastic Viessmann Vitodens 100-W Boiler [2021 model]

** Update New 2021 Model Hydrogen Ready **

If you buy a Viessmann 100-W boiler from Boiler Central, you get a 12-year warranty. Free parts, labour & call outs!

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Viessmann Vitodens 100-W Review

If your looking for a powerful boiler with reliability and energy efficiency then the Vitodens 100-W is the ideal candidate. Add on top the new features and technology including being hydrogen ready and built-in WiFi then this boiler is set to be a hit for years to come.

Ahead of the game, Viessmann is appealing to the people falling into the ‘gas boilers are going to be banned’ trap. Boilers that only run on gas are likely to be phased out, but boilers that can run with a blend of hydrogen (h2) in the gas supply will be being installed for years to come.

The new Vitodens 100-W – Overview

Viessmann Vitodens 100-W Review

Let’s now go to review the Viessmann Vitodens 100 boiler. The Vitodens 100 comes in the 3 main boiler types, combi boiler, a system boiler and a regular boiler. They come in varying outputs so that they’re suitable for as many homes as possible in the UK.

Viessmann name this boiler their best selling gas condensing boiler.

The Viessmann Vitodens 100W boiler is one of the best combi boiler options on the market.

Having Which? Best Buy accreditation, a super easy to use backlit control panel and long guarantees, it’s certainly one of the leading boilers in the UK boiler market today.

Many people ask us:

Viessmann Vitodens 100-W Review

Is the Viessmann 100-W combi or system boiler any good?

Well If you’re looking for a new boiler, they are amongst the best for affordability and are especially reliable in our experience, earning them a Which? Best buy award.

In case any Viessmann Vitodens 100 boiler problems occur they come with a manual. You can also google any issues or ring for a Gas Safe engineer who will be included within your warranty.

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Viessmann Vitodens 100-W Boiler Price Review

Viessmann 100-W System BoilerViessmann 100-W Combi Boiler

Always remember installation fees may not be included in the price.

Price up a Viessmann 100 combi or system boiler in just 20 seconds – click here

Viessmann Vitodens 100-W key boiler information:

Viessmann Vitodens 100-W Review

A highly engineered and affordable boiler system with a super-quiet operation, the Viessmann Vitodens 100-W is the premier system for anyone who needs a new boiler

This gas condensing boiler is an incredibly popular solution for UK homes. It now comes with hydrogen ready capabilities which means it can run on a blend of natural gas and hydrogen to cut greenhouse gasses. Fantastic for reducing your carbon footprint.

With innovative technology, highly efficient service and reliability, and smart tech-ready, the Vitodens 100-W will help you to optimise and save energy.

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Viessmann Vitodens 100-W – Top Features

An easy to use Touchscreen Panel:

Viessmann Vitodens 100-W Review

The Vitodens 100-W wall mounted gas condensing boilers are all equipped with a new easy to use LCD touchscreen.

This makes it easy to access options and settings, especially in the dark.

You can also offer a wireless remote control for even easier access to the system. The new Vitodens 100-W comes with built in Wifi.

Viessmann Vitodens 100-W Size

The Viessmann Vitodens 100-W review also includes its compact dimensions thanks to German planning with fantastic compact sizing, making the system fit into any home decor and easy to place into cupboard space.

With its sleek design, it will fit into any type of home and be your heating powerhouse for many years to come.


Where are the Vitodens 100-W made?

Manufactured in Germany, you can be sure you are getting the best in precision engineering. Being one of the best and most reliable manufacturers of boilers doesn’t come easy in a crowded market. Still, with Viessmann’s experience and know-how, they managed to design and build a remarkable product.

They manage to do this and keep their pricing below others in the boiler installation market but offering the highest reliability on the market.

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Why choose the Viessmann Vitodens 100-W boiler?

Vitodens 100-W Review
Viessmann Vitodens 100-W Review: Heat Exchanger

As with all Viessmann gas condensing boilers, the Vitodens 100-W is equipped with stainless steel Inox-Radial heat exchangers.

Quite simply, this means that the stainless steel heat exchanger will last for donkey’s years, which rivals competitors like Worcester Bosch as they use plastic heat exchangers which are prone to wear and breakages.

This technology brings with it an extremely high-efficiency rate of 98% and exceptionally reliable and efficient operation during its long service life. 

Viessmann guarantees the Inox-Radial heat exchanger for ten years against leaks resulting from corrosion and Boiler Central offers a unique 12 Year warranty on all installed Viessmann new Boilers!

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Viessmann’s superb 4-pipe system boiler:

Viessmann Vitodens 100-W system boiler is a gas condensing boiler made to be wall-mounted.

Viessmann Vitodens 100-W 30kW is very popular, but it is also available as 26kW and 35kW.

Most noteworthy is that Viessmann Vitodens 100 system boilers go up to 35kW. If installed together with a Vitocell 200 or 300 unvented cylinder, they become the perfect system boiler combo when adhering to G3 building regulations.

Viessmann Vitodens 100-W 4-pipe system

This stops the need for an energy cut-off valve and a cylinder overheat thermostat, being integrated into the boiler. 

The Viessmann Vitodens 100 system boilers include a Viessmann weather compensation outdoor sensor installation. The sensor enables the boiler to connect with the outside weather so it can detect if the boiler needs to increase or decrease the temperature.

Viessmann Vitodens 100-W – Quick Review

  • SEDBUK 2009 seasonal efficiency 89.5%
  • Ideal as a replacement for older appliances due to low installed height and installation space for adaptation to existing systems
  • Low operating noise through extended modulation ratio: up to 1:6
  • Modulating stainless steel cylinder burner
  • User-friendly control via backlit LCD touchscreen (option for control via room thermostats)
  • Straightforward access from the front, so no need to leave space at the side for maintenance
  • Also approved for multiple connections to stacks in multi-storey buildings
  • Combined PRV and condensate connection, for fast and simple installation

For affordability (Viessmann Boilers start at £1,695 installed!), reliability, ease of use and space-saving, the Viessmann range is going to be the best choice on the market in affordable boilers.

Don’t just take our word for it either. The Vitodens 100-W is a which? Best buy, and for a good reason.

Not convinced? Let’s explore further specs! 

Viessmann Vitodens 100-W Review
Viessmann Vitodens 100-W
TypeNatural Gas Combi Boiler
Warranty (Years)12 (only with Boiler Central)
Width (mm)400
Height (mm)700
Depth (mm)350
Weight (kg)38
Output (kW)30
ErP Space Heating EfficiencyA
Flow Rate (l/min)12

About Viessmann: Manufacturer Information

Viessmann is a German heating engineering company that aims to provide energy-efficient heating and minimal cost. The Vitodens range is their excellent attempt at doing this. The brand new Vitodens 100 has increased in technology whilst the price has remained the same.

The Vitodens 100-W is available as a gas condensing system boiler for the connection of one DHW cylinder and as a gas condensing combi boiler with an integral plate heat exchanger for DHW heating. 

In the delivered condition, the Vitodens 100-W is set up for operation with a constant boiler water temperature.

By connecting an outside temperature sensor (accessories), the boiler can be operated in weather compensated mode.

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The following are integrated:

One sealed unvented hydraulic system with 2 connections for heating flow and return, and 2 connections for cylinder heating (gas condensing system boiler) or DHW heating (gas condensing combi boiler). 

These boilers are only intended for installation in sealed unvented heating systems. Likewise, boilers for unvented heating systems are also available.

Additionally, if the Viessmann Vitodens 100-W combi boiler is installed in an S plan or Y plan system, then the two internal connections are not used and must be capped off during installation. 

Market leading hydraulic systems

Viessmann combi boiler
  •  Circulation pump
  •  3-way diverter valve
  •  Safety valve
  •  Diaphragm expansion vessel
  •  Plate heat exchanger for DHW heating (gas condensing combi boiler)

The Viessmann Vitodens 100-W is a better and more efficient choice than the Worcester-Bosch Greenstar series.

It is also an upgrade on the Viessmann 050-W boiler, with much better internal components. See our Viessmann Vitodens 050-W review for more information.

What about the cost with higher kW boilers?

Finally, in our experience customers ask us several questions regarding boilers and the heating costs but one that always pops up is: will a higher kW boiler cost me more to run?

It seems like an obvious answer, but actually, the answer is no.

You will heat your home faster with a larger kW boiler with a higher output and then enter simmer mode to keep the water hot.

The smaller boilers will stay firing high for longer to ensure correct radiator temperature to give you the optimum temperature for your home, making them use more gas. 

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Viessmann Vitodens 100-W Cost 

The Vitodens 100-W is priced slightly higher than most of the comparable models from other manufacturers, coming in at an average of £1,879 dependent on your location in the UK.

Other factors will cost you more for your 100-W combi boiler, such as if you need to move your boiler flue or if you need to relocate your boiler to another room.

One thing that people are unsure of is what size boiler they need for their home.

If you click here, you can get a fixed price on a boiler that’s suitable for your home.

You will also see the cost of a Viessmann 100-W boiler if this is the boiler you’re set on purchasing.

We have a range of guides on the recommended boilers to purchase if you need a little more help or for what type of boiler you need for your home.

12-year warranty

We will analyse your number of bedrooms, bathrooms, and provide you with a 100% reliable quote where you can book online and select an installation time that suits you.

All with Boiler Central’s 12-year warranty on all Viessmann boilers and exemplary service.

Boiler Central is the only company to offer a tremendous 12-year warranty on all Viessmann boilers.

Our flexible boiler finance options make buying a boiler online easy.

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