For many people choosing a new gas or oil fired boiler is something they’d prefer to leave to the ‘experts’. However, as you will often receive conflicting advice from installers, a certain amount of background knowledge is essential to allow you to make an informed decision and avoid the disappointment of ending up with a substandard installation that doesn’t live up to your full expectations. Some of the key points you'll need to consider include:
Well over 60% of new boilers installed these days are combis. These boilers provide both central heating and hot water from the same unit and so eliminate the need for a separate hot water cylinder. They suit small to medium sized properties, with up to one bathroom and en-suite, and come in sizes from 24kW up to 40kW, the larger the kW rating of the boiler the greater the hot water flow rate at the taps. If you like to bath a lot, or require more than one tap/shower to work effectively at the same time, then it's well worth considering installing a larger output boiler as one of the most common complaints, especially concerning gas combi boilers, is to do with poor hot water flow rate. This is usually caused by an installer specifying an undersized boiler, (as stated earlier, the larger the boiler output the better the hot water flow rate), or due to poor mains water pressure, something that should be checked by the installer before committing to this type of installation.
Heat only boilers will often be installed in properties which have poor mains water pressure, and so are unsuitable for a combi boiler, as well as larger properties containing several bathrooms which would require a hot water cylinder to meet the higher hot water demand. In addition they can be found on any heating system that requires the installation of a hot water cylinder for safety reasons, such as those containing a multifuel appliance fitted with a back boiler or solar thermal panels. (N.B. If you’re considering installing a wood burning or multifuel appliance, Solar thermal panels or Solar P.V. at some point in the future then it would be sensible to factor this in to any decision at this stage).
It's important to realise that without appropriate guidance from the customer many installers will quote to supply the cheapest boiler they can find fearing they’ll lose the job if they don’t come up with the lowest price. Unfortunately the saying ‘you get what you pay for’ is just as applicable to boilers as anything else. Cheap boilers often come with only a one or two year manufacturers’ guarantee and in the trade are known to be extremely unreliable and expensive to repair; supplying the spare parts is where the manufacturers ultimately make their money. It’s not uncommon for customers to become so frustrated with the poor reliability and repair costs associated with these boilers that they’ll have them replaced after 6 or 7 years, which is only around half the life expectancy of a quality boiler! When you consider that the potential savings to be made between installing a cheap boiler and a quality boiler are only a maximum of a few hundred pounds, which can easily be swallowed up paying for one or two breakdowns, it's hardly worth taking the risk.
As with all major purchases, the best way to assess the quality and reliability you’re likely to get from a product is often reflected in the guarantee the manufacturer is prepared to offer on it. Currently there are a number of reputable manufacturers, including Worcester Bosch, Baxi and Ideal who are providing parts and labour guarantees of between 5 and 10 years on their boilers, which not only says a lot about the quality of the product itself, but could also result in you saving a significant amount of money, as if you currently have an annual maintenance contract on your existing boiler, something that can costs up to £200 a year, this can be cancelled for the duration of the manufacturers’ guarantee.
Where natural gas is available then it will always be the fuel of first choice due to its lower running costs, however if you live in the countryside, and so are ‘off grid’, then the choice will be between LPG or oil. LPG has the advantage of reduced installation costs, the boiler and tank are significantly cheaper to buy than their oil equivalents, and there’s also the additional flexibility with siting the boiler, as LPG boilers are more compact and usually wall mounted. An added benefit of having an LPG tank is that it offers the opportunity to install other gas appliances such as cookers and fires. The main disadvantages of LPG are the two year fixed term contract that you have to sign up to with the LPG tank installers, the premium you'll currently have to pay on the cost of LPG compared to oil, and the numerous restrictions that affect the siting of the LPG tank which could mean, if you have a small garden, that it may not be possible to meet all the regulations concerning clearances from buildings, vegetation and neighbouring properties.
Oil boilers have the advantage of being able to be sited either internally or externally and all combi boiler models will have a higher hot water flow rate than their LPG equivalent. There are also less onerous restrictions concerning siting of the oil tank and you have the freedom to choose when to buy your oil and so, in theory at least, can buy in the summer months when the price is at its lowest. The downside of oil is that the boilers, and associated oil tanks, are significantly more expensive to buy than their LPG equivalents, the boilers are larger and often floor mounted, so if internal space in your property is limited then siting the boiler, especially if it’s a combi, may be a major issue and the price of oil can fluctuate wildly as it's very dependant on the state of the world economy and political instability in the Middle East.
Finally, here's some information to help clarify the difference between older, standard efficiency and modern, condensing boilers. Standard efficiency boilers were generally installed before 2005 (gas) and 2007 (oil), and vary in efficiency from around 60% for some older gas boilers up to 85% for many oil fired pressure jet boilers. Due to changes to the Building Regulations in 2005 and 2007 it is now a requirement, except in a few very limited circumstances, to install condensing boilers on all new gas and oil installations and when replacing an existing boiler. Despite some misleading information, often circulated on the web, condensing boilers are always more efficient than standard efficiency boilers, infact all condensing boilers have an efficiency of around 90%. As a comparison, a 12 year old standard efficiency gas boiler will have an efficiency of around 78%, which means that replacing it with a new boiler would produce a saving of around 22% on a customer’s fuel bill. And as for reliability, we’ve found that this is far more dependent on the quality of the boiler than whether it’s condensing or not, although having an annual boiler service is definately more important in preventing unnecassary breakdowns with condensing boilers compared to standard effeciency ones.
We sincerely hope you've found this article helpful and if you're currently in the process of looking to replace an existing boiler, or install a new one, and would like some further help or advice then you can call us now on 01686 411121 or 07778 809002.