Gas and Oil Central Heating Boilers - Advice to householders
Click on the picture (Acrobat Reader required)

Make sure that you use a VAT Registered Installer, who should charge you less VAT on energy-saving materials. Only 5% VAT on the materials listed in this downloadable leaflet (instead of 17½%). The 5% rate applies to not only the materials but also to the installation charge for those materials. The leaflet gives an example of a correct VAT invoice for a job that includes energy-saving materials.
CLICK here for more information on H. M. Revenue & Customs VAT website.

Dispelling the myths about condensing boilers.

Buying a Heating System.

The expenditure on a heating system is a considerable investment, you will want to make sure you are getting what you need and a system that meets the best environmental standards with the lowest running costs.

The quotation. The institute recommends that you get at least three quotations, this may seem a lengthy process but remember, your heating system will last 10-15 years if installed properly and the initial cost will only be a fraction of the running cost over this period.

Who to get to quote. Use a professional. Members of the Institute are uniquely qualified to install a system designed to your needs, the Institute also has a code of practice that determines our members behaviour, ensuring that your system will give years of trouble free service. Other Organizations to contact include: The Energy Saving Trust and the Heating & Hotwater Information Council, both have networks of installers.

SEDBUK The seasonally adjusted boiler efficiency figures are available on the internet, these tell you just how efficient different makes of boilers are, don't buy without checking here first.

Gas safety. All installers working with gas are required, by law, to be registered with GasSafe, the register of gas installers, please ensure for your own safety that any person providing a quotation for gas installations has the appropriate qualification and carries an ID card to prove this. But just remember that GasSafe registration is only for gas safety; it is not a heating qualification.

Dispelling the myths about condensing boilers.

Condensing boilers have now been available for almost three decades, yet the uptake of these super efficient boilers had been very slow in the UK until legislation was passed requiring their installation in new and replacement systems. Their market share is now growing much faster.

If faced with making a purchasing choice for a new central heating boiler based upon all the facts and possible options, the sensible choice must always be for the most energy efficient option. This will save more money than it costs and will help the environment by reducing carbon dioxide emissions, which is something we all have a responsibility to do and it is rather absurd to waste energy.

So why is the uptake of these "too good to be true" condensing boilers so slow in the UK? I believe it is due to a certain amount of apathy and reluctance in parts of the heating industry, which is renowned for being slow to change and also ignorance by some within the trade and the consumer. One not asking for any choice and the other not offering any. This is then supported by a great deal of myth and speculation sometimes fuelled by irresponsible reports in the media with the conclusion that condensing boilers can't be any good and are too expensive. I can recall video recorders, computers and mobile phones receiving similar treatment!

Very simply, condensing boilers are designed to extract the maximum amount of heat generated from the fuel which is paid for to produce heating and hot water. On older boilers, over £45 can be wasted for every £100 of fuel purchased. This wasted energy is reduced to less than £15 with a condensing boiler. The design incorporates a secondary heat exchanger that usefully uses the heat normally lost through the flue. The flue temperature at the terminal of a condensing boiler is as low as 50°C, compared to as much as 300°C on a regular boiler. We can make another comparison, with cars, where engines have been developed to be much more fuel-efficient and produce fewer emissions. This is now accepted and indeed expected, as is turning a key to start an engine rather than turning a crank at the front of the car. This is progress and we need to get away from the old type of "crank up boiler".

The following are ten of the myths we hear about condensing boilers together with the facts, which will hopefully dispel the myths and help people make the sensible choice when purchasing a new boiler:

1.  Unreliable new technology? Now 25 years of proven reliability, indeed most of the components are also used in regular boilers.

2.  Only efficient when condensing? They will ALWAYS be more efficient than a new regular boiler whether in condensing mode or not by up to 15% and 30% more than older boilers.

3.  Radiators must be oversized? There is only a marginal benefit from over-sizing radiators. Larger radiators will allow slightly cooler water to return to the boiler and can increase the efficiency by a further 3%. However this is not considered to be cost effective and is often impractical, although be aware that radiators sized correctly for a non-condensing boiler flow temperature of 82°C will not produce the same amount of heat when the flow temperature is only 70°C. That is; rooms will not reach temperature in the coldest weather.

4.  Cannot be fitted to existing systems? They can be fitted to most new and old systems. Normal good practice must be followed which will include flushing of system and adding an inhibitor. As with any replacement boiler, an assessment of the effectiveness of the control system and type of hot water cylinder, should also be made.

5.  Difficult to install? Only real difference from a regular boiler is a condense drain which is familiar plastic overflow pipe.

6.  Condensate a problem? Up to 1 litre of condensed water per hour is produced. This has a pH of about 5 which is between rain water and cola. The condense is disposed of through a condense pipe connected to the drainage system.

7.  Pluming from flue? Care should be taken locating any flue terminal. Pluming can be a nuisance to neighbours but numerous flue options are available. The flue gases produced on older boilers cannot be seen due to their high temperature.
The cooler flue gases from a condensing boiler produce a plume which can be seen and is like watching money on it's way to the bank.

8.  Condensing flue products kill plants? Plants thrive on carbon dioxide!

9.  Limited availability? Over 20 different manufacturers now supply a full range of models including condensing combination boilers.

10. Too expensive? The price difference has continued to reduce and in some instances is completely negated by grants currently available from the Local Authority.

Producing heating and hot water accounts for over 70% of the energy used in the home. It therefore makes sense to produce this heat as efficiently as possible. Older boilers are less efficient and can become less reliable with age. The pay-back time for the cost of replacing an existing boiler with a condensing boiler is often quoted as being over 8 years, however the pay-back for the additional cost of about £250 is in fact less than 3 years and often absolutely nothing with a grant!

The other choices are; to do nothing and have no heating if the existing boiler has failed, or to purchase a less efficient regular boiler and pay up to 15% more for the fuel to provide heating and hot water. There is only one sensible choice, and that is the energy efficient one.

There is now a national network of Heating Engineers/Installers who are registered as Energy Efficiency Professionals who can provide details on all options available including condensing boilers. Tel: 023 8066 8900 for details.

Peter Thom Past president IDHEE

Updated by Bill Bucknell Chairman IDHEE, 07/10/2009

Buying a Heating System.

Finding a Member in your area.

Go to the feedback page, complete the form and select "Members by Area", or have a look at the members' website index.