THE BEST & WORST With the average boiler breakdown costing 200, we reveal the brands that won t let you down this winter, so you can spend your money on something more exciting AT A GLANCE Customers satisfaction and the inside view from boiler experts on the brands to buy and to avoid Find out how two newcomers to this year s survey performed The key things to consider when deciding which boiler to go for Choosing a model from a reliable boiler brand will cut the risk of that sharp intake of breath that follows a visit from a technician. It also means that the 200 you might otherwise have needed to spend on repairs can instead be put towards something you enjoy such as a weekend away rather than household practicalities that you should be able to take for granted. Our survey results reveal that Worcester Bosch and Vaillant are the only brands making boilers that meet our high Best Buy standards that is, loved by owners and respected by professionals. But if you can t find a Worcester Bosch or Vaillant boiler or installer you like, or you re put off by their relatively hefty price tags, there are three other brands that we think are also worthy of consideration: Viessmann, Johnson & Starley and Intergas. This year is the first time Johnson & Starley and Intergas have been included in our survey. Both scored well in most areas and tend to be a little less expensive than premium brands Worcester Bosch, Viessmann and Vaillant. Rating reliability In May 2016, we asked 10,859 Which? members about their boilers. To help us bring you results for more boiler brands than ever before, we also topped up the survey with 601 members of the public. And to give an even more rounded assessment of each boiler manufacturer, we surveyed 179 s about the boiler brands they re not affiliated with. This two-pronged approach means that we can give a reliability and customer score for each brand based on the views and experiences of the people who actually own them, as well as an in-depth picture from engineers of the build quality, availability of parts and spares, ease of repair and servicing, and how likely they are to recommend a boiler from each brand. We then turn all this into easy-to-understand star ratings and an overall Which? score, so you can see at a glance the boiler brands you can rely on and the ones it would be best to avoid. 22 WHICH? OCTOBER 2016 WHICH.CO.UK
BOILER BRAND (sample size in brackets) Worcester Bosch (2,297) Impressive results and the brand most recommended by non-incentivised engineers. Vaillant (830) The best of the rest. Reliable, loved by owners and gets the thumbs up from the professionals. Viessmann (134) One of only five brands given a seal of approval for build quality; its boilers are reliable, too. Johnson & Starley (42) An impressive survey debut. One of the most reliable, but engineers need more convincing. Intergas (39) Another new entrant offering reliable, well-built, simple-to-service-and-fix boilers. Baxi (238) Easier than many to service but, despite recent improvements, still only average reliability. Ideal (231) It s easy to get hold of parts and spares for this brand, but it fails to excel in any other area. Alpha (48) Good reliability, but engineers have concerns over ease of fixing common faults. Main (79) Average scores across the board, but engineers are unlikely to recommend it. Potterton (155) Easy to service and find spare parts for, but no more than average in most other departments. Glow-worm (257) Reliability could be better. Mainly average across the other areas. Vokera (56) Room for improvement in many areas, including reliability and build quality. Ariston (64) Engineers say build quality is very poor and they are very unlikely to recommend its boilers. Ferroli (60) Poor reliability, poor build quality, difficult to work on and hard to source spare parts for. OIL BOILERS OWNERS VIEWS Brand reliability Customer score Ease of fully servicing Fixing a common fault ENGINEERS VIEWS Availability of parts and spares Build quality Recommendation BRAND SCORE 92% 83% 76% 75% 63% 56% 55% 54% 54% 53% 52% 43% 40% 29% Worcester Bosch (139) Simply the best oil boiler around according to owners and engineers. Grant (127) Not far behind, but owners reported more reliability issues than with Worcester Bosch. n/a n/a n/a 87% n/a n/a n/a 71% USING THE TABLE Best Buys in red. Owners views Survey of 10,859 Which? members and 601 members of the public, May 2016. Reliability Number of faults each brand developed for owners. Weighted according to boiler s age when it developed a fault and the number reported. Customer score How satisfied owners are and how likely they are to recommend brand to a friend. Engineers views Survey of 179 heating engineers in April 2016 who have repaired or installed the brand frequently in the past six months. Fixing a common fault How easy it is to replace a domestic hot-water heat exchanger. Recommendation Whether engineers who aren t incentivised to install a brand would recommend it. Score Ignores price. Based on: reliability 40%, customer score 30%, engineers views 30%. WHICH.CO.UK OCTOBER 2016 WHICH? 23
Worcester Bosch 92% BEST BUY 1 Reliability 2 Customer score 3 Ease of servicing 4 Fixing a common fault 5 Availability of parts and spares 6 Build quality 7 Engineers recommendation Worcester Bosch continues to impress us with its reliable boilers and happy customers: an extraordinary four in five who own one (84%) are very satisfied with their boiler and more than three quarters (76%) would recommend it to a friend. Heating engineers also heap plenty of praise on Worcester Bosch boilers. It is the only brand that earns a five-star rating for how likely engineers are to recommend it. For this score, we only compile the views of engineers who are not incentivised to install the particular brand. Worcester Bosch s top rating is a ringing endorsement of its quality a view reinforced by engineers five-star assessment of the boilers build quality. Parts and spares are easy to come by, and engineers report little difficulty with conducting an annual service. There are other brands that make it easier to fix a common fault but, on balance, Worcester Bosch is more than worthy of being a Which? Best Buy. Try to make sure you get a Worcester Bosch boiler installed by one of its many fully accredited installers, as they can offer longer warranties. Picking the right installer can as much as double your boiler s warranty. They have great build quality, parts are always available, they re reliable and the aftersales care is fantastic Warranties can last up to 10 years, but the length varies depending on the product and also whether your installer is fully accredited by Worcester Bosch. Vaillant 83% BEST BUY 1 Reliability 2 Customer score 3 Ease of servicing 4 Fixing a common fault 5 Availability of parts and spares 6 Build quality 7 Engineers recommendation Vaillant makes brilliant boilers. The brand is very reliable, has customer satisfaction levels comparable with Worcester Bosch 77% are very satisfied and 67% would definitely recommend to a friend and has the all-important seal of approval from boiler engineers as well. Engineers say it is one of only two brands to have excellent build quality, and even non- incentivised engineers would still recommend a Vaillant to a customer. The boilers are also easier to fully service and repair a common fault on than those from Worcester Bosch. Vaillant misses out on the top spot as customers tend to be slightly more satisfied with a Worcester Bosch and engineers are a bit more likely to recommend Worcester Bosch over Vaillant. This doesn t detract from its high-quality range, though, and there s no question that its boilers are worthy of being Best Buys. As with Worcester Bosch, all of Vaillant s boilers are smart, meaning they can be controlled by a phone or a tablet from any location. If you are considering a Vaillant, make sure you get it installed by an engineer who can give you the full five-year warranty. Vaillant makes a great overall product. They are superbly built and designed appliances. It also has peerless aftersales support Vaillant offers two or five-year warranties, depending on the model and the engineer s level of accreditation, so it s worth checking before you buy. 24 WHICH? OCTOBER 2016 WHICH.CO.UK
WORTH A LOOK WORTH A LOOK Viessmann 76% 1 Reliability 2 Customer score 3 Ease of servicing 4 Fixing a common fault 5 Availability of parts and spares 6 Build quality 7 Engineers recommendation Viessmann is a consistently strong performer in our annual surveys, making very reliable boilers that are liked and respected by owners and engineers. Last year, we reported that engineers found it difficult to get hold of Viessmann parts and spares. The company got in touch, thanked us and said it would improve its UK parts distribution. Engineers seem to have noticed the difference: Johnson & Starley 75% 1 Reliability 2 Customer score 3 Ease of servicing 4 Fixing a common fault 5 Availability of parts and spares 6 Build quality 7 Engineers recommendation It s the first year we had enough responses to include Johnson & Starley, but it was worth the wait. It has the best reliability record of any brand in the survey and a good customer score, too. Engineers have more mixed views. It is one of only five boiler brands considered to offer good build quality but is not as likely to be recommended to customers as the very best, and some engineers report greater difficulties with fixing common faults. The mixed scores could be due to Johnson & Starley being better known for hot-air heating systems, which are niche. It does offer a range of gas-condensing boilers, QuanTec, that are suitable for conventional domestic radiator systems. Two and five-year warranties are available depending on your installer and the boiler model. They ve got good-quality parts and are built well. They have a good reputation Viessmann has gone from scoring two stars last year to three in 2016, so you now shouldn t have to wait too long for a spare part. Viessmann also gets a coveted seal of approval (four stars or more) for build quality from our expert engineers, which makes it one of only five brands to do so. Viessmann offers two, three or five-year warranties on its range. A product on a par with Worcester Bosch and Vaillant. Very reliable Top three buying tips Focus on 1 reliability It may sound obvious, but pick a reliable brand. Our survey reveals that 68% of Worcester Bosch boilers purchased six years ago still haven t developed a single fault, compared with 39% of Ferroli boilers. Don t be 2 afraid to challenge an expert s opinion Your boiler fitter will be an invaluable source of information during the buying process, but many are incentivised to install boilers from particular brands. If they are recommending a brand you don t trust, don t be afraid to insist on a brand that benefits you, not them. Efficiency is 3 more than just a letter There is very little difference in efficiency between the most and least-efficient new gas boilers. But getting the wrong type of boiler, or an oversized one, will mean you are burning more gas than you need to, regardless of the energy rating your boiler has on its label. A good heating engineer will help you pick the right boiler, which depends on how many bathrooms and radiators you have, as well as how many people you live with and your typical hot water usage. WHICH.CO.UK OCTOBER 2016 WHICH? 25
Middle of the road So what about the other boiler brands out there? Baxi, Ideal, Alpha, Main, Potterton and Glow-worm can be described as average. There isn t much in our results to set any major alarm bells ringing; they are just not as good as the two Best Buy and three Worth A Look brands profiled, and our evidence suggests you ll have more problems with them over their lifetime. Worth a go? These brands reliability is OK but could be improved. Alpha has a good record, but engineers say it is quite difficult to fix a common fault and that the build quality isn t that high. Owners also tend to be less satisfied and less likely to recommend these brands. Engineers agree, being more likely to describe the build quality as average or poor compared with the very best boiler brands. That said, these brands boilers can be more attractively priced than brands such as Worcester Bosch, Vaillant and Viessmann. But with the average cost of a repair being almost 200 according to our survey, we think a more reliable brand is a sound investment. If your budget won t stretch, then it s worth considering Johnson & Starley or Intergas both have excellent reliability records. WORTH A LOOK Ferroli, in particular, stands out as a brand that just isn t worth the risk. According to our survey, it has the worst reliability record, a poor customer score, and engineers completely panned it in terms of build quality, the availability of parts and spares, how easy it is to fix a common fault and whether they would recommend it to a customer. We asked engineers why they rated Ferroli so poorly. We can t include all of the comments, but one engineer summed up their feelings like this: How long have you got? They re unreliable, and parts Intergas 63% Boiler brands to avoid 1 Reliability 2 Customer score 3 Ease of servicing 4 Fixing a common fault 5 Availability of parts and spares 6 Build quality 7 Engineers recommendation Dutch company Intergas has grown its UK market share over the past few years. This is the first time we ve been able to report on the quality of its boilers, and we ve been pleasantly surprised. Intergas boilers are reliable, well liked by owners and have caught the eye of heating engineers. It s one of only five brands considered to have good build quality, and its boilers are easy to service and fix. It s a bit are hard to come by. Another now flatly refuses to install Ferroli boilers due to the poor standards: I ve only installed two Ferroli boilers in my 10-year career. I will never install another. Ariston and Vokera also don t cover themselves in glory: both have an average brand reliability record, but engineers think build quality is poor and are unlikely to recommend them. more difficult to get hold of parts and spares than bigger brands, and non-incentivised engineers are a little less likely to recommend one. They cost a little less than the Best Buy Worcester Bosch boilers, though, so it s well worth getting a quote. Two and five-year warranties are available depending on your installer and the model. This is a brilliant boiler. The build quality is top notch and there is much less to go wrong 26 WHICH? OCTOBER 2016 WHICH.CO.UK
Keep your boiler in tip-top condition With the average breakdown costing you 200, it pays to make sure you do as much as possible to nip issues in the bud with regular preventative maintenance It s good practice to have your boiler serviced at least once a year, and not doing so will actually invalidate any warranty you still have on your boiler. But even if your boiler isn t under warranty, an annual service (which usually costs around 70) is still a good idea. Just as your car s tyres eventually become worn down and the brake pads need replacing, boilers also succumb to wear and tear. The engineers we surveyed stressed the importance of preventative work, such as cleaning. Replacing worn parts, such as gas tubes and washers, is also vital to the ongoing fault-free functioning of your boiler. Low standards Our latest investigation has revealed that many boiler services are not up to scratch (see p28), however. When we surveyed s about their opinions on servicing within the industry, many were concerned by low standards. More think servicing standards are poor (34%) than good (27%). But engineers do see a chink of light, with more saying that servicing standards are getting better (37%) than worse (21%). When we dug a little deeper, we discovered some of the causes behind the engineers concerns. Some say that large servicing companies put pressure on engineers to conduct too many services in a single day, which can lead to jobs being rushed. We also spoke to some small-heatingcompany directors who told us they were worried about the standard of some newly qualified engineers they have interviewed. Safety checks Many engineers concerns were about services focusing solely on safety checks, rather than a more thorough look at the boiler s health. The focus on safety checks makes the service more akin to a standard MOT check on your car, rather than a full service that can catch issues before they become a real problem. If you can, get an engineer you know and trust to do your next boiler service. If you prefer to service your boiler through a larger servicing company, make sure you check out our boiler servicing contract recommendations in next month s issue. We also have a handy checklist, for you to make sure your boiler is getting the service it needs, at which.co.uk/boilerservicechecklist. Standard issues Condensing boilers are very much like cars: they need attention at certain intervals, and, from time to time, will need gas tubes, sensors and electrodes replacing. If you carry out this preventative work rather than waiting for the boiler to break down, then it will give many years of trouble-free operation. I have been recruiting for engineers over the past year and am shocked at what some of them call a boiler service. Assuming these are a typical crosssection of the industry, it s scary! Needless to say, they don t last too long with us, but they continue elsewhere doing the servicing. There are a lot of companies that take on bulk service contracts where engineers are not given enough time to complete the service properly; they tend to take an analyser reading and, if the readings are ok, they don t go any further. THE BOTTOM LINE Our survey results reveal that you can get a great new boiler from a reliable, high-quality brand. Getting the correct type and size of new boiler is the quickest shortcut to lower energy bills, and a regular service is important for the ongoing smooth running of your boiler. FIND OUT MORE On Which.co.uk l More than 350 boiler reviews covering all 15 brands included in our survey. In each review, you can find out all of the boiler s key specifications, which type of home it is suitable for, and what owners and engineers think of the brand: which.co.uk/boilers l Find a recommended heating engineer in your area. which.co.uk/trusted-traders Recent articles in Which? l How safe is your boiler?, This issue, p28 l Repair or replace?, Sep 2016, p28 l Should you buy a smart thermostat?, Nov 2016, p66 PHOTOGRAPHY: GETTY IMAGES WHICH.CO.UK OCTOBER 2016 WHICH? 27