Viessmann has built a reputation as one of the most premium and reliable boiler brands available in the UK, and this Viessmann boiler reviews guide, I will explain exactly why so many installers rate it so highly.
From its German engineering heritage and Which? Best Buy history to genuine Trustpilot feedback, pricing and warranty terms, this guide covers everything a homeowner or landlord needs before deciding. Whether you’re replacing an ageing boiler or fitting a new one into a rental property, Eazy Heat can get a new Viessmann boiler installed at your home as soon as the next working day.
Viessmann Boiler Reviews: Key Facts
Before getting into the details, here’s a quick snapshot of the most important facts about Viessmann boilers, covering pricing, warranty, efficiency and reliability all in one place.
| Category | Details |
| Founded | 1917, in Hof an der Saale, Germany, by Johann Viessmann |
| Current headquarters | Allendorf (Eder), Germany, since 1937 |
| Company structure | Privately owned, family-run for four generations |
| Which? recognition | Best Buy status for its Vitodens gas boiler range in 2021, 2022 and 2023, and again for a second consecutive year more recently |
| Trustpilot rating | Around 4.4 to 4.5 out of 5 from over 5,300 reviews |
| Boiler types made | Combi, system and regular (heat-only) boilers |
| Efficiency rating | Up to 94-98% ErP efficiency (A-rated) across the Vitodens range |
| Boiler-only price range | Roughly £790 to £2,600 depending on model and output |
| Fully installed price range | Roughly £1,800 to £4,100 depending on job complexity |
| Warranty range | 2 years standard, extendable up to 12 years with registration and an approved installer |
| Main pros | Which? Best Buy history, industry-leading stainless steel heat exchanger, long extended warranties, favoured by heating engineers |
| Main cons | Higher upfront cost than most rivals, some models need a paid upgrade for the longest warranty |
| Servicing recommendation | Annual service by a Gas Safe registered engineer to keep warranty valid |
Why Should You Consider a Viessmann Boiler?
You should consider a Viessmann boiler because they combine genuine Which? Best Buy recognition with a stainless steel heat exchanger design that’s widely regarded by heating engineers as one of the most durable on the market.
Viessmann’s Vitodens combi boiler range secured Which? Best Buy status in 2021, 2022 and 2023, and more recently the brand’s six most popular Vitodens gas boilers were awarded Which? Best Buy status for a second consecutive year, reinforcing its reputation for consistent quality.
For homeowners who want a boiler that’s likely to perform reliably for well over a decade, Viessmann’s Inox-Radial stainless steel heat exchanger carries its own extended warranty of up to 10 years on many models, separate from the main boiler warranty, reflecting real confidence in its corrosion resistance.
Landlords managing multiple properties often lean towards Viessmann too, since independent surveys have found it to be one of the most recommended brands by professional heating engineers themselves, not just by homeowners.
Compared with a mid-range brand like Baxi, Viessmann sits at a noticeably higher price point, but the gap largely reflects stronger long-term warranty terms and a heat exchanger built to a higher specification.
The Pros And Cons Of Viessmann Boilers
Here’s a straightforward look at where Viessmann boilers perform strongly and where the brand might not suit every budget.
| Pros | Cons |
| Vitodens range held Which? Best Buy status in 2021, 2022, 2023 and again more recently | Generally more expensive upfront than mid-range brands like Baxi or Ideal |
| Rated the most recommended boiler brand by professional heating engineers in independent surveys | The longest warranty terms on some models require a paid upgrade rather than being free |
| Inox-Radial stainless steel heat exchanger carries its own separate extended warranty, often up to 10 years | Standard (out-of-the-box) warranty on most models is just 2 years before registration |
| Warranty can stretch to 12 years on several models when registered with an approved installer | Fewer installers are Viessmann-approved compared with more mainstream brands, which can mean less choice locally |
| High efficiency across the range, with some models reaching up to 98% ErP | Replacement parts can occasionally take longer to source than for higher-volume brands |
| Compact, storage-combi designs on several models fit neatly into a standard kitchen cupboard | |
| Strong Trustpilot rating with the vast majority of reviewers rating their experience as excellent |
How Efficient Are Viessmann Boilers?
Viessmann boilers are highly efficient, with most models across the Vitodens range achieving between 94% and 98% ErP efficiency, placing them among the most efficient gas boilers sold anywhere in the UK. This means that for every unit of gas the boiler burns, up to 98% of that energy is converted directly into usable heat for your home, with very little wasted through the flue.
This puts Viessmann on par with, or slightly ahead of, other premium brands such as Vaillant and Worcester Bosch, since all modern condensing boilers sold in the UK must meet strict minimum efficiency standards. What genuinely sets Viessmann apart is the design of its Inox-Radial stainless steel heat exchanger, engineered specifically to resist the corrosion and scaling that can gradually reduce a boiler’s efficiency over the years.
Because this component is central to how well the boiler performs long term, Viessmann backs it with its own dedicated warranty, separate from the standard boiler cover, giving homeowners real confidence that efficiency will hold up over the life of the appliance.
What Is Viessmann’s Which? And Trustpilot Rating?
Viessmann’s Which? rating has been consistently strong in recent years, with the Vitodens combi boiler range awarded Which? Best Buy status in 2021, 2022 and 2023, and its six most popular Vitodens gas boilers securing the award again for a second consecutive year more recently.
Independent surveys have also found Viessmann to be the most recommended boiler brand among professional heating engineers, a distinction that carries real weight given engineers see a wide range of brands fail or perform well over time.
On Trustpilot, Viessmann UK holds a rating of around 4.4 to 4.5 out of 5, based on more than 5,300 customer reviews, with roughly 75% of reviewers awarding the full five stars.
This is a slightly smaller review volume than brands like Worcester Bosch or Vaillant, which each have tens of thousands of reviews, but the proportion of five-star feedback is comparably strong. It’s worth noting that Viessmann’s review volume being smaller isn’t necessarily a reflection of lower customer numbers, but partly reflects it being a slightly less commonly installed brand overall compared with the biggest mainstream names in the UK market.
What Boiler Ranges Does Viessmann Make?
Viessmann makes three main types of boiler: combi boilers, system boilers and regular (heat-only) boilers, all built under the Vitodens name. Understanding which type suits your property is the first step before comparing specific models.
Viessmann Combi Boiler Range
Viessmann’s combi boiler range includes the Vitodens 050-W, 100-W, 111-W and 200-W, all of which heat water instantly without needing a separate cylinder or tank. The Vitodens 050-W sits at the entry point of the range, with outputs from around 3.2kW up to 35kW, offering solid performance at the most accessible price point in the Viessmann line-up.
The Vitodens 100-W is widely considered the brand’s best-selling model, striking a strong balance between price, warranty length and build quality, and it’s available as a combi, system or heat-only boiler depending on your needs [web:109]. The Vitodens 111-W adds a stainless steel domestic hot water cylinder built into the unit itself, while the Vitodens 200-W sits at the top of the wall-hung combi range, offering outputs up to 35kW and Viessmann’s most advanced controls.
For homes wanting a storage combi with a larger built-in hot water cylinder, the Vitodens 222-F and 242-F models offer stainless steel or enamel-coated storage cylinders integrated directly into the boiler casing.
Viessmann System Boiler Range
Viessmann’s system boiler range is built on the same Vitodens platform, with the 100-W, 111-W and 200-W all available in system boiler configurations designed for homes with a separate hot water cylinder.
These models suit properties with more than one bathroom or higher simultaneous hot water demand, since the system boiler works alongside an unvented or vented cylinder to deliver strong water pressure to multiple outlets at once.
The Vitodens 100-W system boiler is available in outputs including 19kW, 26kW and 32kW, making it flexible enough for everything from a modest three-bedroom home to a larger property with higher hot water needs.
Like the combi versions, Viessmann’s system boilers benefit from the Inox-Radial stainless steel heat exchanger and its associated extended warranty, giving landlords and homeowners genuine long-term reassurance.
Viessmann Regular (Heat-Only) Boiler Range
Viessmann’s regular, or heat-only, boiler range includes heat-only versions of the Vitodens 100-W, designed for older properties that already have a hot water cylinder and cold water tank in place. These boilers suit homeowners and landlords managing period properties where converting the entire heating system to a combi or system setup would be disruptive or unnecessary.
The Vitodens 100-W Open Vent range covers outputs from 13kW up to 35kW, giving plenty of flexibility for different property sizes, and carries the same stainless steel heat exchanger technology and extended warranty options as the rest of the Vitodens family.
Most Popular Viessmann Boiler Models
Certain Viessmann models consistently stand out as the most requested by UK homeowners and landlords, largely thanks to their balance of price, warranty length and proven reliability. The table below highlights the models installers fit most often.
| Model | Type | Output Range | Standard Warranty | Best Suited For |
| Vitodens 050-W | Combi/System | 3.2kW to 35kW | 7 years (up to 10 with paid upgrade) | Budget-conscious buyers wanting Viessmann quality |
| Vitodens 100-W | Combi/System/Heat-only | 3.2kW to 35kW | 7 years (up to 10-12 with registration/upgrade) | Most UK homes, widely considered the best-seller |
| Vitodens 111-W | Combi/System | 25kW to 32kW | 7 years (up to 10-12 with registration/upgrade) | Homes wanting a built-in stainless cylinder |
| Vitodens 200-W | Combi/System | 25kW to 35kW | 7 years (up to 10-12 with registration/upgrade) | Larger homes wanting the flagship wall-hung model |
| Vitodens 222-F | Storage combi | 19kW to 32kW | 7 years (up to 10 with upgrade) | Homes needing a larger built-in hot water store |
How Does Viessmann Boiler Pricing Compare?
Viessmann boiler pricing sits at the premium end of the UK market, generally higher than mid-range brands like Baxi but broadly comparable with other top-tier names such as Vaillant and Worcester Bosch. The table below breaks down typical unit-only and fully installed costs across the combi, system and regular ranges.
| Boiler Type | Model Range | Unit Price Only | Fully Installed Price |
| Combi | Vitodens 050-W | £790 to £1,550 | £1,800 to £3,100 |
| Combi | Vitodens 100-W | £950 to £1,950 | £1,950 to £4,100 |
| Combi | Vitodens 111-W | £1,300 to £1,900 | £2,300 to £3,800 |
| Combi | Vitodens 200-W | £2,000 to £2,600 | £3,500 to £5,500 |
| System | Vitodens 100-W System | £1,350 to £1,800 | £2,700 to £4,500 |
| Regular | Vitodens 100-W Open Vent | £1,350 to £2,200 | £2,600 to £4,200 |
Your final installed price will depend on factors such as the location of your existing boiler, the complexity of any pipework or flue changes, and whether you choose to pay for an extended warranty upgrade. Eazy Heat provides free, no-obligation online boiler quotes so you know exactly what a Viessmann boiler would cost for your specific property before committing to anything.
Viessmann Boiler: What Recognition Have They Earned?
Viessmann boilers have earned strong recognition from Which?, with the Vitodens combi range awarded Best Buy status in 2021, 2022 and 2023, and its six most popular Vitodens gas boilers securing the award again for a second consecutive year more recently.
This puts Viessmann in the same elite tier as Worcester Bosch and Vaillant, all of which have earned multiple years of Which? recognition for their domestic gas boiler ranges.
Beyond formal awards, independent industry surveys have identified Viessmann as the most recommended boiler brand among professional heating engineers themselves, a distinction that carries particular weight since engineers see first-hand how different brands perform after years in real homes.
This kind of peer recognition, from the people who install and repair boilers every day, is arguably just as meaningful as a Which? Best Buy award for homeowners trying to judge long-term reliability. Combined with its 100-plus year history of German engineering, Viessmann’s track record positions it firmly among the most trusted boiler brands available in the UK today.
Viessmann Boiler Warranty: What Do They Offer?
Viessmann boiler warranties start at 2 years standard out of the box, but extend to 7 years free of charge on most Vitodens models simply by registering the boiler within 30 days of installation.
From there, homeowners can pay for further upgrades, typically extending cover to 10 years and, on several models including the Vitodens 100-W and 200-W, up to a full 12 years when installed by an approved Viessmann installer.
The Vitodens 050-W follows a slightly different structure, with its maximum extended warranty capped at 10 years rather than 12, while the 100-W, 111-W and 200-W can all reach the full 12-year term.
Separately, Viessmann’s Inox-Radial stainless steel heat exchanger often carries its own extended warranty of up to 10 years, which exists independently of the main boiler warranty and reflects the brand’s confidence in this specific component’s corrosion resistance.
As with all major manufacturers, keeping up with an annual service from a Gas Safe registered engineer is essential to maintain warranty validity throughout its full term.
Compared with Worcester Bosch, whose top-tier warranty also reaches 12 years through its own accredited installer scheme, Viessmann’s terms are very closely matched at the premium end of the market, though Viessmann’s free 7-year registration warranty gives it a slight edge for buyers who don’t want to pay extra upfront.
| Model Range | Standard (Out Of Box) | Free On Registration | Maximum Paid Upgrade |
| Vitodens 050-W | 2 years | 7 years | 10 years |
| Vitodens 100-W | 2 years | 7 years | 10 to 12 years |
| Vitodens 111-W | 2 years | 7 years | 10 to 12 years |
| Vitodens 200-W | 2 years | 7 years | 10 to 12 years |
How Much Does It Cost To Service A Viessmann Boiler?
Servicing a Viessmann boiler typically costs between £80 and £140 for a standard annual check by a Gas Safe registered engineer, slightly higher on average than some mainstream brands due to the more specialised components used across the Vitodens range.
Keeping up with annual servicing isn’t optional if you want to protect your warranty, since missing a service year can significantly reduce your cover, particularly if you’ve paid for one of the extended warranty upgrades.
During a service, the engineer will check the flue, inspect gas pressure and safety controls, and examine the condition of the Inox-Radial heat exchanger and any filter fitted to the system. For landlords, it’s worth scheduling the annual Viessmann service alongside the legally required gas safety check for rental properties, since combining both visits can save time and reduce overall call-out costs.
Are Viessmann Boilers Worth It?
Viessmann boilers are worth it for homeowners and landlords who want a genuinely premium boiler backed by Which? Best Buy history, an industry-leading stainless steel heat exchanger and a reputation as the most recommended brand among professional heating engineers.
Where Viessmann makes the most sense is for anyone planning to stay in their property for the long term, since the combination of a free 7-year registration warranty and the option to extend further gives real peace of mind that few mid-range brands can match.
Viessmann may be less suitable if you’re working with a tighter budget, since the upfront cost is noticeably higher than mid-range brands like Baxi, and the very longest warranty terms on some models require a paid upgrade rather than coming free with registration.
Finding a Viessmann-approved installer locally can also be slightly trickier than with more mainstream brands, since its installer network isn’t quite as extensive. For most UK households that prioritise long-term durability, proven engineer endorsement and genuine Which? recognition over the lowest possible price tag, Viessmann remains one of the strongest choices on the market, and as a nationwide installer, Eazy Heat regularly fits Viessmann boilers for customers who want that extra reassurance.
Ready For A New Boiler? Get Your Free Quote From Eazy Heat
If Viessmann sounds like the right fit for your home, or you’re still comparing your options, Eazy Heat makes the whole process simple from start to finish. We provide expert new boiler installations to homeowners and landlords right across the UK, with next day installation available so you’re never left waiting around without heating or hot water.
Our Gas Safe registered engineers take care of everything, from the initial survey through to installation, warranty registration and ongoing servicing advice. Get in touch with Eazy Heat today for your free, personalised boiler quote and find out exactly what a new Viessmann boiler would cost for your home.
Frequently Asked Questions
Can You Get Finance For A Viessmann Boiler Installation?
Yes, most UK installers, including Eazy Heat, offer finance plans that let you spread the cost of a new Viessmann boiler over monthly instalments, often ranging from 12 to 120 months depending on the lender and your credit profile. This can make premium models like the Vitodens 200-W far more manageable, since you’re paying a smaller monthly amount rather than the full cost upfront.
Are Viessmann Boilers Compatible With Smart Thermostats?
Yes, Viessmann boilers are compatible with most major smart thermostats, including Hive, Nest and tado, as well as the brand’s own ViCare app and Vitotrol smart controls, which allow remote heating management through a smartphone. Several Vitodens models also feature a built-in 7-inch colour touchscreen, giving you full control directly from the boiler itself without needing a separate device.
How Long Do Viessmann Boilers Typically Last?
Viessmann boilers typically last between 15 and 20 years with regular annual servicing, which is above the UK average for gas boilers, largely thanks to the durability of the Inox-Radial stainless steel heat exchanger. This component’s resistance to corrosion and scaling is a major reason Viessmann backs it with its own dedicated extended warranty, separate from the standard boiler cover.
Do Viessmann Boilers Work Well In Hard Water Areas?
Viessmann boilers can work well in hard water areas, and the brand’s stainless steel heat exchanger offers better natural resistance to limescale build-up than some cheaper materials used by other manufacturers. That said, Viessmann still recommends fitting a scale reducer or water softener in particularly hard water regions, such as much of the South East and East Anglia, to protect the wider heating system and help maintain warranty eligibility.
What Should I Do If My Viessmann Boiler Shows An Error Code?
If your Viessmann boiler displays an error code, you should first check it against the official fault code guide in your boiler’s manual or through the ViCare app, since many common issues, such as low pressure or ignition faults, often have simple fixes that don’t require an engineer visit. If the fault persists or appears more serious, contact a Gas Safe registered engineer, ideally one approved by Viessmann if your boiler is still within its extended warranty period, to avoid affecting your cover.
