Efficiency boilers recover and utilize heat that would otherwise be lost and wasted through the use of high-efficiency or condensing boilers. It uses less gas to produce the same amount of heat as standard boilers. High efficiency condensing boilers convert 86% or more of their fuel into heat, compared to 65% for old G rated boilers.
The boilers are used to create heat and can be installed anywhere. Where there is a boiler, an A- grade, efficient boiler can be used.
How it works
Efficiency boilers extract heat from the exhaust gases that would otherwise escape. Most boilers, especially G grade boilers, consist of a single combustion chamber enclosed by the waterways of the heat exchanger through which the hot gases can pass. These gases are eventually expelled through a flue, located at the top of the boiler, at a temperature of around 180°C. Efficient A-grade boilers are designed to allow the heat to rise upwards through the primary heat exchanger. When at the top the gases are rerouted and diverted over to a secondary heat exchanger. These can reduce the flue gas temperature to about 55°C. This reduction of temperature causes the water vapour, which is formed during the combustion process, to condense. Droplets of water then form and by gravity, they fall to collect at the base of the flue. The remaining gases are expelled to the outside environment through a fan-assisted balanced flue. The condensation produced within the appliance should be drained as necessary into the waste discharge pipe work or externally into a purpose-made soak away.
It is only possible for a condensing boiler to work to these very high efficiencies if the flow and return pipe work is also kept below 55°C. The flow & return temperatures need to be maintained for the heat transference to occur from the flue to the water i.e. heat transference goes from hotter to cooler materials. This process reduces the emission of exhaust gases.
There are two different types of condensing boilers that can be fitted:
- Regular Boilers
- Combination Condensing Boilers
Condensing boilers heat your hot water through a hot water cylinder and Combination condensing boilers give you instant hot water without the need for a cylinder. These boilers are the most efficient available and captures much more usable heat from its fuel. The heat exchanger in the boiler system makes sure that as much heat as possible is transferred from the boiler"s burner and the least amount of heat is lost in gases through the flue.
Benefits
- The efficiency of a typical non-condensing boiler to convert fuel into heat is approximately 60%, whereas efficient modern A-rated condensing boilers are at least 90% effective.
- A-rated condensing boiler will also use a third less fuel than an older boiler and it would provide the same amount of heat.
- Replacing an old G rated boiler with a new A-rated condensing boiler can save up to a quarter on your heating bills straight away and up to 1,300kg of CO2 year.
- If everyone in the UK with gas or oil central heating installed a high efficiency condensing boiler with full sets of heating controls, we would save enough energy to heat nearly 1.9 million homes for a whole year and save around 6.7 million tonnes of CO2.
- The government has introduced a ‘Boiler Scrappage Scheme’ in which up to 125,000 households are offered £400 towards the cost of upgrading their boiler from an inefficient one to a high efficiency A-rated one or a renewable heating technology.
Installation and where it can be used
The efficient condensation boiler can be installed into most places to replace the old system, and it will immediately start working to reduce carbon emissions.