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Boiler Warranties & Guarantees: Which Brand Offers the Best Value?

The importance of a new boiler warranty

Warranty: noun

A written guarantee, issued to the purchaser of an article by its manufacturer, promising to repair or replace it if necessary, within a specified period of time. 

The boiler warranty is an essential part of choosing a new boiler, as in the long term it can potentially save you thousands of pounds in repair costs. 

Not just that but you want the peace of mind that if something does go wrong you'll get your boiler back in working order fast and at no additional cost. 

Boiler Warranty and Guarantee Guide

The simple rule is that you want the warranty to be as long as possible and ideally be a guarantee and not just your usual warranty offer, so in this guide, we'll be answering all of the need to know boiler warranty questions, including: 

  • Which brands offer the best boiler warranty? e.g. length 
  • What's the difference between a boiler warranty and guarantee?  
  • Conditions of cover - how do you keep your warranty valid? 
  • How do you register your boiler warranty? 

Boiler Warranty vs Guarantee - What's the difference? 

A guarantee is an agreement that the manufacturer will attend to the property to repair or replace the boiler unconditionally if related to a manufacturing fault. 

A warranty is a contract to only investigate the problem, but not an agreement to necessarily fix the boiler free of charge. 

As a result, a guarantee is seen as the superior option, so is certainly worth bearing in mind. Keep reading to find out which brands offer a guarantee. 

Conditions of Cover 

Many people aren't aware that there are conditions you need to meet to keep your boiler warranty valid for the entire coverage period.

Yet the reality is most boiler brands outline a few key requirements you need to meet to maintain your warranty, these commonly include the following: 

  • Installed by a registered Gas Safe Engineer 
  • Registration of the warranty within 30 days of installation 
  • Annual boiler servicing by a registered Gas Safe Engineer 
  • In the event of a breakdown, you are typically asked to pay a deposit before an engineer attends 

Having issues with your combi boiler? Read our boiler problems and solutions for quick troubleshooting guidance. 

Manufacturer warranty lengths

There is no one size fits all when it comes to manufacturer warranties. Each boiler manufacturer set their own and this can vary between their different ranges and models.

All boiler brands typically include a standard warranty ranging from 1 to 5 years, but in today's competitive boiler marketplace, most manufacturer's offer a free extended warranty that ranges from 2 to 10 years. 

Boiler Manufacturer Period (Years) Guarantee or Warranty? 
Viessmann 5-10 years Warranty
Ideal  5-10 years Warranty
Worcester Bosch 5-10 years Guarantee
Vaillant 5-10 years Warranty
BAXI 3-10 years Warranty

Which boiler manufacturer offers the best warranty? 

New boilers are pivotal to the smooth running of your home so finding a warranty that you're comfortable with is certainly important and common sense says, the longer the warranty - the better.

So which brand offers the best warranty in terms of value? 

Currently, the winner has to be Worcester Bosch boilers. 


  • They offer a guarantee (not just a standard warranty)
  • The length is 10 years as standard (when purchased via Heatable) 

Worcester Bosch also extends the guarantee terms to their other products if installed at the same time as the boiler e.g. the Greenstar filter. 

Just make sure you follow the usual protocols for keeping your warranty valid, which includes: 

  • Installed by Gas Safe Engineer in accordance with instructions 
  • Annual boiler service 
  • Registered within 30 days of installation 
  • You may be asked to pay a deposit before engineer attendance 

Also make sure that if you're paying monthly for a new boiler installation, the warranty length matches or exceeds the payment period and dodge the risk of paying for a boiler that's broken and out of warranty.

Situation, boiler warranty registration. How to register the boiler.

Make sure the warranty is registered within 30 days or risk losing the warranty entirely.

Many heating engineers will leave the boiler warranty registration to the homeowner, so do make sure to ask.

If you happen to have purchased your new boiler through Heatable - we'll take care of this for you, registering the boiler warranty immediately with the manufacturer - you'll receive confirmation from Viessmann or Ideal in the post or by email within 4 weeks.

Read all about our guide to the ideal warranty and see how it compares to Worcester Bosch's whopping 10 year guarantee. 

If you live in an average-sized home, see our guide on choosing the best boiler for a 3 bedroom house

Claiming on your warranty - who’ya gonna call?

Howling at the moon if your boiler requires attention will never help - whether the boiler is under warranty or not.

So call the boiler manufacturer...

All new boilers from Heatable come with either a 5-year or 10-year warranty through Ideal boilers and Viessmann respectively. Both manufacturers have outstanding reputations for customer warranty service and won't include a call-out charge for warranty claims.

In the unlikely event that your under warranty boiler does require attention, you should contact the manufacturer directly and can do so using the below contact details:

Ideal boiler warranty line: 01482 498 660

Viessmann boiler warranty line: 01952 675 000

If you haven't purchased your boiler through Heatable then you should start to panic and make phone calls to anyone and everyone to check who is going to uphold your boiler warranty.

In order for your Heatable boiler warranty to be upheld, you'll simply need to ensure that you're having it serviced by a Gas Safe engineer once every year.

If your condensing boiler was installed through another party, you'll need to make sure that you registered the boiler warranty within 30 days of installation, had the boiler installed by a Gas Safe engineer adhering to any and all industry and manufacturer regulations and that you're servicing the boiler annually.

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

How to retain your warranty and notes on a scandal and the boiler blame game 

One thing to watch out for on the battlefields of boiler warranty terms; blame.

Need quick advice on all things boiler buying? - Glance over this article, described by the New York Times as 'A Triumph'

Manufacturers will only act upon claims if they believe the fault truly lies with their product and is not a consequence of poor or incorrect installation.

So inevitably for some unlucky customers; the installer blames the boiler and the boiler manufacturer blames the installer. Leaving them in cold water no man's land, dodging flying shrapnel from between the crosshairs of installer and manufacturers alike.

This is why Heatable works closely with Viessmann and Ideal boilers, not only because of their product quality but very importantly, the quality of their aftercare service and warranty claim teams.

In the theme of scandals, read about why you should certainly consider, possibly, maybe but definitely cancel your boiler cover, here.

Boiler gadget warranty claims

Is my smart thermostat covered?

The likes of Nest, Honeywell & Danfoss might be the nation's most popular path to enlightenment of energy usage and will all come with their own standard warranty, if correctly installed of course and massaged into place by an experienced thermostat charmer but they won't be covered under the same manufacturer warranty as your boiler.

Only manufacturers own thermostats like the Ideal Touch Connect will be covered by the manufacturer warranty if they're installed at the same time and registered.

FREEBIE ALERT: Every compatible Heatable new boiler installation will come complete with a wireless ESH thermostat, guaranteed by the manufacturer for 2-years.

It is said that approved Heatable installers can summon a thermostat from its packaging with nothing more than expressive dance and some natural yoghurt.

Congratulations, you now have the equivalent of a GCSE Grade D in boiler warranty studies.

How to get the best deal (and longest warranty) on a new boiler

Without boasting, buy from us.

We're an online, nationwide boiler installation business with 500+ 5 star reviews from a shed load of happy customers.

Because 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 combi boiler replacement. Plus, because of the volumes that we install, we're able to access exclusive warranty lengths from our partner manufacturers. For example, we can offer 10 years of protection on the Viessmann 050 range, whereas your traditional installer can only offer you 7. Boom.

Plus, all of our combi boiler installations come with upgraded wireless controls, as well as an Adey magnetic Pro Filter and powerful chemical protection.

To get the best deal on a new combi boiler, answer some quick online questions and we'll give you an instant fixed price.

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Heatable is registered in England and Wales No. 08804726 (VAT No. GB205805920 ). Trading address is 1 Station Road, Great Sankey, Warrington, Cheshire, WA5 1RH. Heatable acts as a credit broker (not as a lender) and offers credit products through a panel of lenders. Heatable is authorised and regulated by the Financial Conduct Authority (reference no. 805259).

[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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