/ Home & Energy

Is it worth paying for boiler cover?

Our annual boilers survey has revealed a surprising nugget: those who pay for boiler cover could be better off forgoing their contract and paying for repairs on an ad-hoc basis. Do you pay for boiler cover?

Almost half of gas and oil boilers will develop at least one fault that needs a repair within the first six years of its life. Of course, getting yourself a Which? Best Buy boiler is a good idea, and drops this to fewer than two in five.

Despite the likelihood that your boiler will eventually develop some faults, we’ve found most people who own a boiler would be £50+ a year better off without boiler cover.

We compared the cheapest servicing contract (£183 per year), which includes an annual service, against the experiences of 5,322 Which? members who don’t have cover. Instead, these members paid for repairs on an ad-hoc basis as well as a yearly boiler check-up. The great majority (93%) are still better off without boiler cover to the tune of £50 or more.

My boiler servicing story

I’ve owned my combi gas boiler for just over three years now, having inherited it when I got the keys to my two-bed flat. I’ve never paid for boiler cover, but I have incurred some costly repairs. Here’s my story (violins).

About two years ago I woke up on a bank holiday weekend with water leaking from somewhere within the casing of the boiler. Being a bank holiday it was difficult to get hold of a plumber, but eventually I found one who was willing to interrupt his weekend to come out and take a look. He diagnosed the problem as a couple of corroded washers and came back the following day to replace them. The cost of the parts that needed replacing – £15. Total cost of call-out and repair on a bank holiday – £261. Ouch.

As a result of that rude introduction to boiler maintenance, I now pay £85 for a service each year to keep my boiler in good working order.

So in the three years I have owned my boiler, I calculate that it has cost me £431 to maintain it. This is the first time I’ve added it up and that seems like a lot for three years – I keep my fingers crossed that I won’t need any more costly repairs going forward!

My experience tallies pretty well with the results of our survey – even though I had a pretty costly repair to shell out for in one year, one of the unlucky few; I would have had to pay at least £549 over the last three years for even the cheapest boiler cover contract, so I am now more than £100 up.

I’ll continue to pay for an annual service and then any repairs as they come up as, despite my bad experience, I don’t see much value in a servicing contract at the moment. I might get scalded again with costly repairs, but for now it feels like an acceptable risk.

Your boiler servicing stories

So, how about you? I would love to hear about how much your boiler has cost you. Are you, like me, in the 93% who are better off without insurance? Or one of the unlucky 7% who have incurred very costly repairs?

Further, are we giving boiler cover too much of a hard time? It would be great to hear from those of you who have had great value from one of these contracts.


Unless you are buying a new property, one of the questions prospective buyers usually ask is, how old is the boiler and does it have a service record.

I used to have a boiler contract with British Gas until one of their engineers decided to pop a ‘sorry you were not home’ card through my letter box even though I was on the other side of the glass door and watched him disappear as quickly as he arrived. I decided then not to renew my contract and opt for an annual service with a local company. My boiler which is an old floor standing type is 19 years old and has been serviced every year without any major faults.

If you shop around you can save quite a lot. My last service cost £60 with a company who does special discounts for seniors which amounted to almost half to what I paid for my loyalty with the original company.

My bungalow had a one or two year old gas boiler when I moved in in 1982. I take it apart annually to check it and remove dust. Since then I have replaced two thermocouples, at a total cost of £7.

A new boiler would be considerably more efficient but probably not nearly so reliable. Service engineers have advised me to keep my old boiler.

[Warning to other readers: please don’t try this at home and use gas safe registered engineers. Thanks, mods.]

Might one ask whether you are qualified to open and work on a gas boiler?

No I am not. I regard myself as a competent person and I am not doing work for anyone other than myself.

As a ‘competent person” – which for ‘gas’ purposes is legally defined, could you share with us the exams which you passed?

You may wish to check out the law before answering of course.

I have passed no exams, but I trust my own skills more than some of the qualified people I have seen in action. I would not carry out any major work such as replacement of a boiler, just inspection, cleaning and thermocouple replacement.

Could you possible therefore explain what exactly a thermocouple does?

Sorry to but in – I just wanted to say (regardless of any laws as I am not 100% sure) that I see no harm in anyone doing tiny little bits of housekeeping work on the boiler if, like wavechange, they understand what they are doing.

The world has gone health and safety mad these days!

On my boiler the thermocouple is used to provide a small current to keep the electromagnetic gas valve open. If the pilot light goes out, the gas supply is shut off. It’s effectively a flame failure device.

Absolutely no problem Lee – and I totally understand your point and in many cases agree entirely.

Just that having seen so many very dangerous (well meaning) DIY gas maintenance attempts, that have actually completely missed obvious (to the qualified) faults, I feel duty bound to warn against such practices.

Wavechange also, please don’t mis-interpret my comments – I have nothing personal going on here – just genuine concerns.

Have you any idea about correct combustion and ventilation. I wouldn’t expect you to. I have no idea what industry you are in, but I would bet you know far more about it than me.

Please do read this:


And ask yourself if by any chance a thermocouple ‘controls the flow of gas’. (I think you may have answered that)

Genuine best regards – genuinely well meaning.

I certainly get things wrong sometimes.

You are absolutely right, Lee. I have the installation and servicing instructions for my boiler and I understand what I am doing and the potential dangers. I have discovered numerous problems with gas installation and servicing done by qualified professionals. In my home, I found that the one of the unions for a replacement gas meter was left leaking because it had not been tightened, the people who installed a new gas boiler for my parents left a serious leak under the floor and ignored instructions about the size of the gas supply pipe, and I have found unsealed boiler casings on two occasions in friends’ houses. I have no idea how common such problems are, but Which? has found examples of poor boiler servicing in the past.

I can and will say no more than…….please, Wavechange, do get the boiler properly checked over and serviced by a properly qualified and ‘Gas Safe’ registered engineer.

If you are a member, check on Which Local for somebody recommended near you.

Also – if rolled out in your area, check out Which Trusted Traders – all completely properly vetted by ‘Which’

On your last point, again I can totally agree and sympathise. Which has indeed found examples of poor servicing in the past and I cannot deny that we still come across many examples ourselves

As in any industry though, we shouldn’t tar everybody with the same brush. There really are some good guys (and girls) out there.

I wish you good health.

I am certainly not offering any general criticism of qualified engineers. I have the manufacturer’s instructions and I have discussed the work I have done with qualified engineers. If I had been incompetent then perhaps this would have been apparent at some time in the past 32 years. I have carbon monoxide and smoke detectors nearby. One of the reasons I don’t involve the professionals is that the boiler has an asbestos seal on the flue, and I don’t want my reliable boiler to be condemned.

Perhaps I should have mentioned that I have, as a research scientist, worked with flammable gases including hydrogen, at high pressures. I know my limitations and would never touch anyone else’s boiler.

I respect your skills in the high pressure flammable gases industry.

I leave this link for those who may be tempted to service their own boiler.


Do please enjoy the rest of your evening

Hi wavechnage

When it comes to boilers and gas , we cannot stress how imperative it is that you use gas safe registered engineers.

As previously quoted, the Gas Safe Register website has plenty of information, and you can find plenty of said engineers on Which? Trusted Traders and Which? Local as well. We also have a discussions section on Which? Local where many gas safe registered engineers are able to answer any questions you may have.

It’s also Gas Safety Week (15th – 21st Sept) at the moment and there’s lots of valuable information out there for consumers.

All the best

Which? Local

Thank you. It would be very interesting to find out how companies featured in Which? Trusted Traders and Which? Local perform when used in an undercover investigation of performance.

Just to show wavechange isn’t alone, my dad built his own boiler, and serviced it for many years, when they got round to getting British Gas to do it the younger engineers had no idea about what to do so my dad would tell them, the older engineers loved working it. It worked well for over 40 years. The new boiler goes wrong annually. He didn’t build that one.

I am certainly not suggesting that anyone else should service their own gas boiler but in the interests of safety it is well worth looking for any sign of problems and having a carbon monoxide alarm near to every gas appliance. I suspect that there are many who don’t bother to have their gas boilers serviced until they break down.

My neighbour discovered his gas pipe had been disconnected under his floor – the previous owner had bent the gas supply pipe that had been subsequently been cut…We are all grateful that we were not blown up by a slow gas leak. So beware of simple solutions by well meaning diy enthusiasts. Had our new neigbour not pulled up his floor boards, had the pipe actually leaked gas, we would probably have never known the cause of our untimely and sudden deaths…

gas brains says:
15 November 2014

yep,use a as safe engineer,toilet cleaner one day,pays your money,gas safe engineer.remember gas safe always,run by capita,you know,congestion charge people,oooops sorry.

gas brains says:
15 November 2014

sounds great,a gas watchdog run by capita,they do the congestion charge, nothing like calling the experts. soooory,

gas brains says:
15 November 2014

a few bodies ive noticed lying about.

I had boiler cover with British Gas from November 2008 to March 2012 and for me it was worth it. It got to a point British Gas was coming out pretty much once a week. I remember one time I had 3 British Gas vans all parked outside my house for the best part of 8 hours.

In the end the boiler fully broke down March 2012 and they could not fix it. When I bought this house in 2008 I was told the boiler would not last 6 months so 4 years at what £7-£8 a month? It was worth it for me.

As for now. Well I have had no boiler since the old one broke over 2 years ago & I am very happy saving that £7-£8 per month, plus have a £0 gas bill now so am saving £20 per month that way too.

We have come far too reliant on central heating / radiators. Why not stick a jumper on and treat yourself to a high tog duvet? works for me & do not miss my boiler at all!

gas brains says:
15 November 2014

youre learning.

My boiler cover comes with my bank account package along with other things like AA breakdown cover, Home emergency cover, Travel insurance etc.
I use all these things, and have called them out for the boiler a few times as well.
For me this is a good value package.

gas brains says:
15 November 2014

moses did part the red sea then

Are boilers necessarily the right answer?

I have warm air heating. This is a sensible design decision when you have huge panes of glass that means solar gain is quite rapid. The original hot air heater was 44 years old when I decided to replace it as spare parts could be a problem. However more to the point I could buy a 90% + efficient closed system from the same manufacturer in the US.

I have always felt that the combination of water, radiators, and the boiler provides many potential problems. Given the choice I will never have that kind of heating system.

Cleaning the filters and a quick hoover is all that is required from me. Apart from the initial one year professional hoover and Check – up £80 is all that is it has cost me in 5 years.

When we move I will be looking at all the modern alternatives to the traditional UK boiler. This would probably be a heat pump system , and apparently these can be retro-fitted to existing radiator systems and supply hot water.

I have known people replace warm air systems, mainly because of noise and lack of controllability. The latter problem should be easy to rectify. It’s easy to design a small house with warm air heating but I suspect it would be harder to install a new system.

Heat pumps are particularly attractive in rural areas with no mains gas supply.

DT: Coincidentally I had a leaflet put through my letter box yesterday advertising 16kW Air Source Heat Pumps, 16kW Ground Source Heat Pumps and 25kW ‘wood pellet’ Boilers with not much detail except for claims of up to 30/40% savings on heating bills. Can you explain a little more about the efficacy of these systems as you have expressed an interest when next moving house?

gas brains says:
15 November 2014

no don’t,for gods sake stop thinking.

They are all of interest but I do not follow the developments religiously. There have been significant improvements in air pumps in the last decade when I was first looking at all the types you mention. So when I move I would then re-examine my options taking into account the type of house I am moving to..

Wood pellet is an interesting one but I suspect proximity to a wood pellet source would make it more attractive. Ground source requires some land [or a lake] in the convential use though drilling down is feasible. Air-source is probably the most common method.

This is quite a good history of the theory and its explosive growth in Japan over the last decade and a half:
and Wikipedia covers most other energy converters with links to learned pieces.

Any of the systems you mentioned would be I suspect a considerable expense so you need to take into account your existing systems operating costs and life-span, your own : ), and whether you could achieve most of what you want in another way.

Just to add to the confusion there do exist gas fired boilers which incidentally produce electricity!! a relatively new development now commercialised. I would avoid them currently as I like the technology to have been around several years for the warts to show.

On a belt and braces approach a wood pellet burner – a type that does not require electricity -would insulate you against electrical shortages/ russian inspired gas shortages.

Many thanks DT. It seems quite a complicated procedure to me but no doubt an energy saving prospect. The Company who posted the leaflet is Energy My Way at http://www.energymyway.co.uk. where you will find there is certain criteria to be met before being considered suitable for instalment.

Beryl – Thanks for the link. Interesting site.

The wood burning option I would always be keen to see if they can be run sans electricity rather than have a generator in the event of power outages.

For the payback times I would be interested to know if that included any servicing costs or not – it may well be noted somewhere on the site.. When I looked at these systems first there was no Govt. assistance so the economcs should have improved.

I had had my old boiler for 15 years with no problems. A valve failed so that the radiators never got hot. I called British Gas for a one-off repair and he duly fixed it. I signed the paperwork and then he scrapped my boiler, disconnected the gas to the boiler, and turned the gas off at the mains. He said that a gasket was faulty. When I asked why he didn’t just replace the gasket he said that the gasket was no longer available. This turned out to be a lie. THEN he asked if I wanted a British Gas salesman to visit and quote me for a replacement. I told him, and his salesman, to F£$% off.

I got a new boiler with a 7 year warranty. I have not decided what to do when it expires but you can bet your life that British Gas will not be considered.

Sadly banjo – this is all too common a story.

One important thing though…..please do ensure that your installer services the boiler annually as you will most likely find that this forms part of the T’s & C’s of the 7 year warranty.

Do tell all your friends about your experience – as a member, ‘Which Local’ is a great place to find local trades that don’t treat you like BG did.

The boiler is an Alpha and there is NO requirement for a regular service during the full 7 years. Nice one. I had a leaky valve, rang them on Sunday afternoon, the repair bod was at my door before 9:00 on Monday. Thoroughly recommended.

Excellent result – but don’t ignore regular servicing – for safety if nothing else.


gas brains says:
15 November 2014

I always wondered where the artful dodger went.

I believe it was Private Eye who dished the dirt on BG and its pressure on repairmen to produce sales well over a decade ago. I see from this that there was still pressure in 2010 and to be honest I doubt it has changed much:

I totally agree with this analysis. Since we moved into our house in 2001, we have had no fewer than THREE boilers. The one sold to us by British Gas was ruled unsafe by THEIR engineers after a year or so! We had a service contract with them and their engineers were worse than useless. They were constantly phoning their office to tell them how to do things, they installed parts the wrong way round, etc. etc. They left us in mid-winter without heating or hot water for days at a time. We finally got a local plumber to install a new boiler. British Gas had never flushed out the pipes, for instance and our new Corgi registered plumber told us that the gas pipes are far too narrow, meaning we cannot add a gas fire to the system.

Hi Josephine – This is just so common.

Thankfully you are confirming that there are some decent (‘Gas Safe’ took over from ‘Corgi) engineers out there who will do it properly.

Thanks for your post.

For some years now we have not bothered with an annual maintenance contract but do have an annual boiler service at a current cost of around £60 from one of the larger local central heating companies. The engineer is always willing to help with optimising the efficiency of the system through tweaking of the controls and checking that everything was working correctly, even the ball valves in tanks in the loft; British Gas never went there! We have never had a breakdown since we stopped using BG. They were always trying to sell something else or recommend a replacement part even though there was plenty of life left. I formed the impression that upselling more important then carrying out a competent and adequate service. Our new house [Dec 2012] has an unvented mains-pressure system which is considerably more complicated than a conventional vented gravity system. Installation of these systems is controlled under the Building Regulations and it is an absolute requirement that it undergoes an annual inspection. These systems are fitted in most new houses with more than three bedrooms as they cope better with drawing hot water simultaneously from two or more outlets; a combination boiler is usually recommended for other houses. Before buying a new-build house, we viewed scores of other properties and in every case I asked about the heating system and the boiler as well as when it was last serviced; in most cases we got some fairly vague answers [and sometimes complete ignorance] so I would suggest to anyone buying a house to factor in a complete system check and overhaul if you proceed to purchase. If there is no recent service record it is safe to assume that it hasn’t been done for some time [whatever the owner says] and it might be worth trying to get a price reduction.

One of the things that most service companies push is a power-flush to purge the radiators of all the accumulated clag that settles in the bottom of the radiators. Depending on the size of the system it can be a big job and take some time, which is why it is quite expensive [around £300 and upwards]. Getting sound advice on whether that is really necessary in any individual case is difficult so it’s probably worth shopping around a few reputable companies for that service [it doesn’t need to be done very often but if a system hasn’t been dealt with for ten years or more it would probably benefit].

Good balanced post JW – and very sound advice about service history as this is being brought up on more and more house sales.

Power flushes do work and make a difference, but as you say, “Getting sound advice on whether that is really necessary in any individual case is difficult so it’s probably worth shopping around a few reputable companies for that service [it doesn’t need to be done very often but if a system hasn’t been dealt with for ten years or more it would probably benefit].”

John – There should be no need for power flushing if the system contains a sufficient amount of the correct corrosion inhibitor. Any reputable company should add corrosion inhibitor when commissioning a new system. I’ve taken radiators off to decorate and know that the inhibitor is keeping them free from the ghastly black sludge that will accumulate without this protection.

Hi wavechain – am not going to get drawn.

Have a good weekend

On unvented cylinders, they are indeed covered by building regs (G.3) but I have not come across a requirement for an annual inspection. The whole idea of the regs is that problems are visible via the tundish or discharge pipe. That said, it’s not a bad idea to check for signs of water deposits or leakage at the tundish and check the external pressure vessel on systems other than Megaflo. If I were buying a house with such a system I’d check that the installation label was properly signed by a registered installer.

Thanks Jak – I think the point I made about having an annual inspection of an unvented system was more to do with the warranty [and household insurance as well I suppose] than with the Building Regs which are only concerned with the proposed installation. This inspection presumably also includes a check to make sure that the various safety interlocks between the pressure system, the water inflow and the boiler are all working satisfactorily. Good point about the installation label being correctly signed and dated – I’ve just looked at the label on our system and although there is a name and address [and we also have other documentation from the housebuilders] I wouldn’t place much reliance on the potential traceability of the person who installed it!

And thanks Wavechange for the point about corrosion inhibitor. Certainly any new system should be properly protected. I was mainly thinking about what to look out for when considering the purchase of a pre-owned home. There is a general paucity of information available at the pre-purchase stage on such a significant component of the property. A good survey would no doubt cover the basics of the central heating & hot water system but I doubt whether they would check for corrosion inhibitor. Over time people change radiators, extend the system, and experience minor leaks, all of which can affect the adequacy of the inhibitor remaining in the circuit. I should be interested to know whether the modern small-bore systems are as free-flowing as the old ‘half-inch’ flow & return pipes serving the radiators.

Having read through all these posts I was beginning to wonder when someone would mention the water side chemical treatment. This seems to be “the elephant in the room” with hot water circulation heating systems. So I totally endorse wavechange’s comment above. Just to let you know my background I am a 62 year old retired professional mechanical engineer who is totally hands on & have 45 years experience of all types of infrastructure plant & maintenance including a chemical factory’s steam raising gas fired boiler plant. Needless to say I have serviced my own boiler for many years, it has cost me next to nothing & it has never broken down. Now I do appreciate that very few people are in this position but getting back to the water side treatment issue. We have lived in our house for 26 years and in the early days redecorating involved isolation & removal of radiators. I was horrified at the dense black sludge which inevitably ran out on the carpets when I removed them. This sludge is iron oxide and is formed due to corrosion of the steel radiator material when exposed to dissolved oxygen in the circulating water. I carried out a process of inhibited hydrochloric acid descaling/desludging followed by a neutralisation treatment, followed by inhibitor addition which prevents this kind of corrosion. Several full system fills, operation cycles, & flushes are required between each stage so it is a labour intensive process but the cost of all the chemical treatments is between £50 – £80. I can assure you this is an absolutely worthwhile exercise & if I drain my radiators now the water is almost crystal clear even if it has been in the system for many years. So if your system leaks or is topped up it is absolutely essential to replace this inhibitor treatment at the same time. I suspect the reason that power flushing is now commonly recommended is that it is cheaper to do compared to the labour intensive process I have described – but in my opinion it will never be as good. Apart from the reduced maintenance aspect, running a clean water side enables best efficiency from your system, all other aspects of burner management etc. being correct.

Hand held infra-red guns – around £13 – make radiator watching a breeze if you want to see cold spots. Also great in the kitchen for jams and sugar work, and in the laundry for washing machine temperatures. : )

I suspect it will also reveal damp spots on wallls where thermal bridging is taking place. Quite e neat and cheap tool.

As Andy says the black sludge that can accumulate in radiators is iron oxide. In an old fashioned system with a header tank in the loft it is worth checking for hot water ‘pumping over’ into the tank, which introduces a oxygen into the circulating water and helps accelerate corrosion.

I am not certain how long corrosion inhibitors last but I have changed mine every eight or ten years and the water in the radiators stays clean.

In contrast, my parents has considerable problem with black sludge, especially in a very long custom made curved radiator. They could not use a corrosion inhibitor because the old heating system included a primatic hot water cylinder. One of the radiators even developed a leak due the extent of corrosion.

Just to add to the chemical cleaning v power flushing considerations. With chemical treatment no part of the system is untouched by it providing all bleed points are vented to ensure all air is removed from the system. Power flushing on the other hand relies on water flow velocity to displace & entrain accumulated solids & carry them out of the system. It is extremely unlikely that all parts of the system will be cleaned effectively by this process as there will inevitably be low flow velocity areas due to the system configuration. I agree with wavechange, inhibitors should be replaced every ten years, ideally this will entail a full system drain & refill with fresh inhibitor added & venting to remove all air.

On the need for power flushing or inhibitor I believe that open systems (fed from a header tank) generally experience more corrosion than sealed systems. As well as inhibitors and cleaners it is now popular to incorporate magnetic filters to catch sludge.

I guess the service companies push the power-flush method in preference to the full descale and chemical treatment process because the health & safety considerations and training requirements are more manageable and economical. I have virtually no scientific knowledge but I still wouldn’t trust most of the guys who have dealt with our systems over the years to handle hydrochloric acid safely in any shape or form without spilling some; I don’t suppose the inhibiting additives neutralise its destructive properties on first encounter – I think it’s more of a post-attack protection for the internal ferrous parts of the system. Seems to be a highly specialised form of treatment that is best left in the hands of highly trained and qualified experts [not literally, of course – they should have special gloves].

John, I think Andy’s approach with hydrochloric acid was a little unconventional. The normal approach is to add a cleaner to the circulating water, leave it for some time, and then flush out the system and put in new inhibitor. It’s not complicated and I doubt that any training is normally involved. The products are widely available, made by Fernox, Sentinel or own-brands.

On this topic it is worth mentioning that there are a few ways of testing circulating water. One can buy test kits where you add a chemical and look for a colour change. Or one can put some of the circulating water in a sealed jam jar with a clean steel nail inside. Without inhibitor the nail goes rusty extremely fast.

Jak, Fully agree with your comment about open vented [older] systems being more prone to oxygen ingress [it is soluble in water – that’s how fish survive] & hence internal corrosion of steel components.
Jak/John, Don’t get too panicked by the term “hydrochloric acid” it is in fact one of the key ingredients of off the shelf system cleaning products and not something I cooked up in “Professor Mad’s” laboratory. In fact I always use Fernox products, they are not the cheapest but I have absolute faith in their efficacy. As regards safe handling let’s get real here – untrained people squirt a highly inflammable liquid called petrol into their cars by the million every day.

Thanks Jak. We had a normal power-flush, using Fernox, done at our previous house so I know there is nothing to worry about at all. I have an aversion to the domestic use of powerful chemicals so I wouldn’t want hydrochloric acid to be used to purge the heating systemis even though it’s also an ingredient in various domestic toilet cleaning products. The safety warnings are so strong I avoid having such products in the house. Andy’s analogy with petrol dispensing is interesting: unless my eyes decieve me a lot of untrained people also manage to spill a lot of petrol on the forecourt; the vapour is highly volatile and even the excitation of a mobile phone has been known to cause an explosion in certain conditions. Petrol stations usually sell cigarettes and sometimes you see somebody light up as soon as they leave the premises to walk to their vehicle.

Anyway, back to boiler servicing and on a different tack: finding a good company is the tricky bit. Which? did a report on this a year or two ago and I don’t recall any of the major organisations coming out of it particularly well on a combination of competency and cost. The cheapest is probably not going to be the best but paying a high price does not guarantee a good system service [or a good emergency response if on a full maintenance contract] either. With a very high percentage of properties in most of the UK having a hot water radiator system of some sort or other there are a lot of annual services to be done and there is a huge amount of competition for this business. British Gas dominates. It trades on its overall reputation and experience, scale and coverage of operation, target response times and declared ability to deal with anything, and a sort of “peace of mind” virtue reinforced by its homely adverts and general approach. Personally, having tried both types of company, I tend to favour large local firms whose vans you see outside lots of local houses – they know the territory, have worked on most of the system types found in the area, have a local depot carrying a full range of spares [and enough clout to get major components at a good price], and employ local people who have a loyalty to the company. As an intermediate level of service, there seem to be a lot of two- or three-man firms who proclaim they are ex-British Gas but can do it cheaper and I expect some of them are also very good; personal recommendation or “Which? Trusted Trader” sampling would be a good starting point. Any Gas Safe registered engineer can do a competent job but I also want one who doesn’t mess the house up in the process and try to persuade you to have some unnecessary extra work done.

Hi dieseltaylor, I would be very interested to know who supplies the infra -red gun which can detect cool areas in radiators. In the recent past I have tried unsuccessfully to obtain a pipe thermometer from local plumbing suppliers. From what you say the infra-red gun is a better device.

You can find these items at Maplin or on eBay.
I was in a Maplin branch yesterday & they do a pen sized one now [code N62LK] at £14.99
Larger pistol grip style ones start from about £30.

Graham says:
20 September 2014

My boiler dates from1988. I never have it serviced. I have a carbon monoxide detector for the very unlikely but potentially deadly even of the casing seals failing and leaking the gas into the kitchen. boilers are designed to operate safely. Unfortunately the servicing industry has successfully kidded the general population into thinking that an annual service actually prevents breakdowns. There is no evidence that any servicing prevents breakdown, nor that it enhances efficiency. Nor is there any evidence to connect the Earths rotation around the Sun with the time interval a service might be required.

Inspection and testing of the combustion process and casing and flue integrity though are different matters.

But it serves the industry to baffle and confuse while the consumer just pays up. Changing my boiler given my £600 per year gas bill isn’t a viable proposition, and I doubt the longevity of the newer boilers. KISS.

Graham, You must be a kindred spirit!. Last year I removed my 42 year old Harford-Unical Hotspur oil boiler that was installed when our house was built. It was still working well & was of an incredibly robust & simple design. OK it’s efficiency was never going to match modern pressure fed atomising oil burners with a condensing section incorporated in the furnace chamber exit….but it cost me nothing to maintain & almost always fired up first go. The real reason I changed it was that the few electrical components that it required are now obsolete & I thought it would only be a matter of time before something failed…..in a record cold snap with a house full of visitors of course.

Colin Hodgson says:
20 September 2014

As an alternative to power flushing
I had my system cleaned with the Magnaclean method , in 2011 , when my installation was ten years old . The amount off black gunge removed was truly amazing , new Fernox was of course then added : the installation has been perfect ever since . My plumber ,Argent , in Worthing , has all the kit .

It will astound many to know that for a long time several leading boiłer manufacturers on their international websites billed their boilers as highly reliable. As an installer I concur to this view, but only after certain conditions are met:

1) Always install with compensation controls that keep the boiłer temperature as low as is possible without compromising comfort. Weather comoensation falls into this category.

2) Always use good quality filters

3) Do as the Germans do, and avoid chemicals. Indeed my own experience leads me to believe even inhibitors do harm over time.

Briatin doesn’t really have anything other than importers of heating technology, and real knowledge and expertise dissapeared along time ago. The resulting vacum has given all sorts of opportunities to all sorts of of interests..

Hi Alec, Am I right in thinking that your first comment about keeping the boiler temperature [hot water discharge] as low as possible is because, for condensing boilers to actually deliver the energy savings so loudly claimed for them, the water must not be too hot otherwise it will not condense the water vapour [mainly from the combustion process] that is present in the flue gas & therefore recover the latent heat/energy contained within it. This has always struck me as bit odd & perhaps a little known fact about condensing boilers & it is simply this – they may only be in condensing mode for part of their operation.Obviously with a boiler system starting from cold the hot water discharge, which is routed through a heat exchanger [commonly called a condenser in this application] in the path of the flue gases at the exit from the combustion chamber, is relatively cool & so condensation & energy recovery does take place. As the circulating water heats up then there may come a point when condensation of flue gas water vapour is no longer taking place due to its dew point temperature being exceeded . So in reality a compromise has to be made, if you want maximum energy saving you have to accept that your boiler thermostat is set a relatively low level [say 60C] – this means that it takes longer to heat your home than if it was set at 80C. I really don’t think many people appreciate this fact. It may well be that with sophisticated modern control systems they have no option to exercise any control over this anyway.

Hopefully service engineers can give householders advice as to using boilers efficiently when they visit to service or repair boilers.

I can understand that a condensing boiler must not be run too hot or the efficiency will be decreased but presumably if the temperature is low, there will be loss of efficiency due to short cycling. Or can the efficiency be optimised by sophisticated modern control systems?

I agree with your comments on condensing boilers being more efficient at the lower temperatures. And that is the headline figure % you see quoted. I also suspect that because you are operating at a lower temperatures the pump needs to operate more and therefore that is also a cost which may or may not be factored into the overall efficiency figure.

Rather like some other campaigns to reduce energy use you sometimes feel that all the facts are not being provided.

Yes, I am afraid the Green political agenda is unlikely to have presented us with a truly objective summary of the all the facts on condensing boilers. Lower set operating temperatures invariably means more cycling on & off of the burner system & so more wear & tear on electro-mechanical components etc. etc.
Of course the simple fact that in the early days the condensate drain pipe was often routed to an external drain point such that it frequently froze solid often resulted in flooding within the boiler has to be a classic example of the triumph of stupidity over technology.
There is a pretty good technical bulletin written by a London plumber who I would have faith in at this website:

L Bambridge says:
21 September 2014

I bought a house advertised as ‘completely rewired throughout’. when I paid for a full building survey by Templars Building Surveyors in Baldock I expected the survey met the RICS list of contents and would ‘save me thousands’. I received a survey that estimated costs to £10,000 but overall the clarity fo the survey was not there, and despite trying to pursue a line of enquiry with the emails I got not better understanding of the property. One of his advice notes was to test the electrics ‘on occupation’ and ask for certification for downlighters.
When I entered the property I discovered the house was a complete DIY botch job and not the hosue that needed a few ‘decorative issues’, there was damp and there was something rotting smelling under the floorboards and these floorboards did not meet the edge of the walls, plaster fallingoff and hollow and so on. Therre were very old electric pendulums and swtiches around and I found by badgering my solcitors that they had not asked for the correct Part P document I had explicitly asked for. The suveyos had ignored the old lighting fittings and the firm who had done the work offered the Part P which said ‘partial rewire’. After over six motnhs Niecic the trad body that is supposed to regulate itself turned up BUT ONLY AFTER WE HAD PAID £300 for a condition report by a firm for the gas and electrics that confirmed the electrics were sfae but were not rewired completed and old wires of 20 years old were in the house still. the gas boiler was safe but as I made more and more enquiries I found that whilst you need a certificate for fit a boiler you do not need a certificate for a gas cooker or an electric cooker or even to lay a gas pipe! Effectviely the surveyors had been remiss and the solicitors lazy but overall the govt allows estate agents to advertise what the sellers say because …and here is the crux…to get a court case up you have to find another RICS surveyor to act as a witness to the bad survey and you have to pay £200 to inspect electrics then another estimated cost of a case for £40000 to take to court. To fix the 3electics is £1000 but of course I would never have bought the house at all had I known that the survey was so lacking in accuracy. And NIECIC agreed that a usual complete rewire would have new lighting fittings and switches. the survey or says he didn’t see it on his inspection and there is nothing – except be prepared for a £40K case that you can do about the survyeors being ‘negligent’. And if you did take a court case there is nothing whatsoever stopping this firm from settling withyou and then doing the same ‘blindeye’ to the next and next and next and next client. The gas pipes and all the other issues which may or may not have been peformed by professionals I will never know beause the solciitors decided that once contracts were signed that they didn’t need to get the documents they had not bothered to get, and what is more frightening is the Legal Ombudsman has appeared to agree that once a law firm fleeces you that they have no obligation to correct their faults…not that I have any faith now in Ombudsman services as this is business redress scheme paid for by the lawyers (not a real ombudsman) and the employees are not legally trained. I also found out that the downlighters are a contravention of a rudimentary building regulation and fire hazard which could have been pointed out in the survey but alas, like the damp, the rot and the shabby diy , were not ‘seen’ by the surveyor.

I will never be able to recover financially from the burden of buying an overpriced slum, because we discover each week more and more about building regulations which the survey ignored as contravened. We have asked the RICS that surely they cannot advertise a buidlign survey with contents on their website but then have no responsibility to the clients who get nothing like the standard they advertise but here is the SCAM the rics THEN says that they have no control over what their members decide is a building survey and no – there is no govt rgulations – so that you can get a good effective survey from firm A and a bad one from firm B and the only way to assess if it is bad is to pay another several thousand to the REICS expert witness – that is ifyou can actually get one to agree to help you – and if you have a spare several thousand pounds. If you have trusted the RICS logo and advertising to buy a full building survey would you then trust to buy another ‘expert’ RICS to assist you to take to court the first? I am concerned that if the firms continue with shoddy unregulated do-as-they-please surveys then they as likely to be expert witness firms as well. The other factor of course is that the firm has jeopardise my investment but also my life by ignoring clearly a misrepresented house that was quite visually indicative that it was not completely rewired or had non fire rated lights and ignored mentioning this safety aspect to the buyer. With gas pipes and the use and fitting being able to be ‘fitted’ by botch job DIY is it right a survey tells the buyer to get a condition report ‘on occupation’ and not before?
With Part P being the legal documentation that electricians are judged by is it right the solicitors just said ‘whoopsie, we could not be bothered to get that specificially requested document and so gave you verbal assurances of electrical safety because we know the Legal Ombudsman will back up our failings and poor standard of service?

Horrendous story but the answer lies in your first paragraph, where despite the lack of clarity the surveyor indicated remedial costs of £10,000. That would have had all the alarm bells ringing for me.
I am afraid we are still plagued by certain professions who are only interested in one thing – billable hours!

It is worth checking when employing any firm to type into search engines the name of the firm and “problems with” or something similar. Your surveyor does get an adverse mention but only one and recently. There are worse surveying firms out there.!

You do not advise when this purchase took place and whether you physically viewed the property yourself both of which are of interest. There is a dispute resolution process with RICS, and also if required specialist legal firms that can act. The firm does have indemnity cover.

As for your unnamed solicitors it would seem that you may have cause for a complaint to the Law Society on grounds of incompetence if they failed to provide all the necessary documentation.

However, you may feel that the energy required to take these actions is unlikely to bring much redress, and also only you know whether the fact that the surveyor suggested £10K of works really should have been a warning sign not to proceed until everything was satisfactory to your own mind.

Buying property is a big deal and I sometimes think people should spend some money/time/ reading on what problems houses in general have and what to look at for yourself so you can intelligently discuss the report with the surveyor.

I used to have a boiler maintenance contract with Corgi, until an experience a few years ago.
My boiler stopped working in the middle of winter, and the house became very cold!
I called the Corgi helpline (available 24 hours, for you to call them that is, not that they will come out 24 hours as I discovered), and they scheduled an appointment for a local gas engineer to call in a few days time.
In the meantime the boiler did start working again briefly, but then stopped. I waited in all day on the day the engineer was to call, and of course the boiler started working again shortly before the man eventually called. He stepped in – I explained that it hadn’t been working most of the time the last four days but had just started working again, he said well, if it ain’t broke I can’t fix it, and left. Two hours later it stopped working again, and my family had a very cold night.
In the morning I rang Corgi, and they rescheduled an appointment for a few days time. It was now the weekend and they couldn’t arrange it any sooner. The same thing happened again, the boiler started working again an hour or so before the engineer called, late afternoon, so when he came in it was working, so he did nothing and left again. Then it stopped again.
I called in a local gas engineer I found for myself who looked at the system, and immediately found the fault, which was to do with the switch which regulated whether the hot water and/or heating turned on and off. It was turning the heating off whenever the hot water went off, and the hot water was set to come on for an hour and a half in the early morning and in the late afternoon, then go off, but the heating should have remained on.
The problem is that with a maintenance contract you are bound to use their services, and their terms and conditions, and to wait for their engineers, and their engineers are paid call-out fees to attend but then can’t be bothered to do anything if they don’t have to. If you engage an engineer yourself he will find the problem for you as he is working for you, not for the maintenance contract company, so will follow your instructions not theirs.
I cancelled my contract with Corgi and told them what I thought of their system. It was an easy fault which should have been discovered quickly, my family should not have had to endure almost a week of cold nights first.

I’ve have a BG homecare policy for something like £12 a month. I don’t auto renew as they don’t reward loyalty so when the current policy runs out I’ll wait however they deem necessary for me to be treated as a new customer and get cashback on the deal. I guess I’ve been using them on and off like this for 15 years +

I’ve only ever needed one call out where they replaced a PCB, although from my sisters experience of BG homecare that’s they’re standard answer to anything that could take more than 5 mins to investigate.

What I have noticed over the last few years is that I no longer get an engineer to do the annual service, I get a salesman 🙁

I find the peace of mind is worth more to me than the £12 a month it costs.

My sisters experience on the other hand shows how poor BG are, her BG installed back boiler ( they used sub contractors) apparently was never installed currently and after 15 call outs in 10 years BG actually got an engineer from the manufacturer to visit with their engineer. This engineer spotted the problem within a couple of mins, something that the dozens of BG engineers failed to do when they just replaced the PCB. Something to do with the in and out flow pipes needed to be the same length and they weren’t. I did write to BG suggesting that the flowchart their engineers use to diagnose faults should be updated with this useful new information so as not to keep replacing PCB therefore saving them time and money as well. But alas I’ve heard nothing more from them.

I read the which recommendations for boilers. A local company installed, according to them, the ‘Rolls Royce’ of boilers. The plumber confided later that it was a cheap job lot the boss got!

Not long after the installation the boss’s son mended our boiler and later the boiler company’s plumber said the son had ‘cannibalised ‘ the boiler.

I wrote a polite comment to that effect on here but it was removed by WHICH with no notice or explanation therefore company has glowing reports!

I now pay privately for the boiler company’s plumber to service the boiler annually and I pay for any breakdowns.

If you read the plumbing trade magazines, which I read about once a year, you will see that indeed the boiler manufacturers do incentivise companies to buy particular boilers in bulk.

Linda I am sorry to note your post has been censored though I can appreciate that Which? may be a bit touchy on the libel front.

It would be interesting if you provide the type of boiler and when it was fitted just in case a search on the Web reveals any interesting information. Ditto a search for your heating company may be of interest to you.

Hi Linda, we can’t find evidence that any of your comments have been removed. I have also checked with our Which? Local team, as I think it’s likely that you’re referring to the reviews you’ve made on there. They have confirmed that all of your submissions are live. If you’re still concerned about this, please get in touch with me here: https://conversation.which.co.uk/contact-us/

Earlier this year a company cleaned and serviced an oil-fired boiler that had locked out. It seemed to be working fine but locked out again the next day. It could be reset but would lock out again after a few minutes or a longer time period. The same engineer came back, confirmed that it was set correctly and examined several components before deciding to replace the main circuit board. All seemed well but the boiler locked out again before I had signed the paperwork. Then a second part was replaced. I pointed out that the circuit board he had replaced could not have been faulty and asked for the original to be refitted. If I had not done so, the bill would have included the costly replacement of a part that was not needed.

I have no reason to believe that the service engineer had deliberately replaced a part that was in working order but I wonder how often unnecessary spares are fitted to boilers and other household appliances.

Hi wavechange, sounds like a situation where your so called “engineer” did not have the skills, training or experience to diagnose the problem. All through this thread this fact seems to be a commonly encountered problem. I am afraid as a professional engineer that I regret the word is so loosely used to describe what are in reality technicians. This would not be a problem if such technicians had been properly trained & vetted but to add insult to injury in many cases they are not.
Clearly the likes of British Gas are not doing anything to improve matters but I suspect that if you had a service contract with a boiler manufacturer such as Worcester Bosch [having installed one of their products] you would see an improvement. In Germany there is absolutely no difficulty in differentiating between engineers & technicians.

Andy – I have done a fair amount of repairs to electronic and electrical appliances – as a hobby and never for payment. Intermittent faults can be the hardest to deal with, so I don’t blame the service engineer for switching the circuit board for a new one. I would have done the same because it seemed the most likely way of correcting the problem. What I do blame him for is not to have put back the original circuit board after establishing that this was not the problem. Incidentally, this was not my boiler but I had offered to be there when the service engineer was visiting.

I don’t know if the guy who came to fix the boiler was an engineer or technician but at least he carried spares for this Worcester Bosch oil-fired boiler and clearly had experience working on that model.

My main reason [apart from cost] for switching my boiler service company was due to the failure of a thermocoupling which was replaced at the time of the annual service. Although the original was still working perfectly I was informed that this was common practice as the thermocoupling was the part that was most likely to fail. Just over 3 months later the boiler went cold on me. I contacted the company and an engineer called the same day and duly replaced it for which I was informed I would not be charged. About 1 week later I received a bill for £108 for the call out + labour. It all makes sense now when I read Wavechange paid a total of £7 for two thermocouplings!

I decided there and then that having paid £118 for the annual service only 3 months earlier I would not be paying a further £108 for fitting a thermocoupling that was in my opinion not fit for purpose under the Sale of Goods & Services Act and sent a letter to this effect. I heard no more from them and have now switched to another local company who services my boiler at almost half the cost.

Beryl – I don’t think it is reasonable for you to have been charged for replacement of a thermocouple if it had been replaced three months earlier, unless there was some provision in the terms and conditions in your service contract. It seems very wrong for a bill to have been issued when you were told there would be no charge.

A contract should really cover servicing and repairs. It is then up to the company to decide whether to replace the thermocouple (I could buy a universal thermocouple in a DIY store for £7.82 and I expect the trade will pay less) or take the chance that it will survive another year.