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High Efficiency Central Heating System Components - Condensing Boilers and Programmable Timers

written by: •edited by: Sarah Malburg•updated: 12/3/2010

With the price of fuel rising worldwide, we should be looking at ways to conserve energy in fossil fuels used by the installation of a high efficiency central heating system. Government grants are available for fitting high efficiency oil and gas condensing boilers to your existing heating system.

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    Fossil fuels are rapidly depleting as more and more energy is required to satisfy our lifestyles.

    Oil and gas will be the first to be depleted, probably about the end of this century with coal lasting another few hundred years or so.

    It is imperative that we conserve the stocks of hydrocarbons and eke them out until an alternative type of energy, preferable renewable can substitute them.

    High efficient central heating systems are an ideal method of conserving our dwindling stocks of oil and natural gas.

    This can be achieved by fitting high efficient condensing boilers in conjunction with thermostatic control valves and good pipe and tank insulation. The use of timers and thermostats will also improve the efficiency of the heating system.

    This is the next article in the series on energy savings in the home, which describes the condensing boiler and the associated programmable timers in more detail. Following articles will describe the other essential components which are required for a high efficiency central heating system.

    We shall start by having a look at the old basic central heating systems, some of which are still giving good service, but are grossly inefficient. We then move on to the current high efficient systems which use condensing boilers and programmable timers.

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    Basic Oil and Gas Central Heating Systems.

    Oil and gas central heating systems became popular in the mid-seventies with the discovery of North Sea oil and gas, with the rush for gas being the popular catch phrase of this era.

    These replaced the old systems of electric hot air circulating and off-peak electric panel central heating, which were very inefficient, expensive and difficult to control. Coal fires had back boilers which heated the domestic water and ran a few radiators fairly efficiently (the opinion at the time being that as you had a fire burning in the grate, you might as well use the excess heat). But of course in those days, you had to relight the fire in the morning. Many a cold morning I sat and lit the fire before going out to work at 6AM. This meant the house and water was nice and warm for my wife and children when they got ready for school.

    However, the early oil and gas heating was still inefficient but no-one was bothered about this as there was an abundant supply of cheap oil and gas.

    The big problem as far as inefficiency was concerned, was the absence of timers, radiator thermostatic control valves and very basic boilers which were operated manually, or by crude timing devices. The pipes were large in diameter and lacked insulation, the hot water tank often having little proper insulation.

    Well so much for the old days, we shall now have a look at a modern gas or oil efficient central heating system.

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    High Efficient Central Heating System Components

    As noted in the introduction, this consists of a condensing boiler – the essential component in an efficient heating system.

    The next improvements needed would be a good timer, TCV’s on the radiators, a thermostatic valve on the hot water tank and the system piped with insulated micro-bore or standard size copper piping.

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    Condensing Boiler Operation

    A condensing boiler operates on the principle that the water content of the fuel is condensed in the combustion gasses. A heat exchanger is used in the flue to transfer this latent heat into the water returning to the boiler from the radiators so the boiler needs less fuel to reheat the circulating water.

    This boiler can be 80-90% efficient compared to the older type of central heating boiler which can be as low as 50% efficient.

    There are government grants, local authority grants and energy supplier grants which have different criteria, so they should all be investigated before purchasing a new boiler for your central heating system.

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    Central Heating Programmers and Timers

    These are an essential component designed to increase the efficiency of the heating system. Early timers were notoriously difficult to operate (a degree in electronics being required, alright, a little sarcastic), but the new ones can be bought in a supermarket, installed by an electrician and are very simple to operate.

    Timers are used to set the start and finish times that you want the boiler to operate, switching the radiator heating on and off as well as the hot water system heating.

    You can set these criteria up to about six or eight times a day – same or different times every day, and different times on weekends. The timer we have on our gas central heating system also has a wee button to press to change between British Winter and Summer times. This saves a lot of resetting, so look out for this when purchasing a new timer.

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    The old central heating systems used to heat our homes were very inefficient by today’s standards, some having an efficiency as low as 50%. These included the solid fuel type such as heating run from the back boiler in an open fire. Electric central heating consisted of electric hot air heating and electric off-peak storage heaters. Oil fired central heating boilers came next, which made a big improvement to cost, but were still pretty inefficient. The dash for gas followed with the advent of plentiful and cheap North Sea Gas, so most of the people of Europe opted for gas central heating.

    Nowadays, we still have a selection of different energy sources to run our heating, including those from renewable sources (discussed in future articles). However, the most efficient fuel is gas in combination with a condensing boiler which uses the boiler exhaust gasses to reheat the water returning to the boiler. These can be as high as 90% efficient.

    The installation of a good digital programmable timer compliments the system's efficiency, starting and stopping the central heating and domestic water heating at preselected times to suit your lifestyle.

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    Sketches of a Condensing Boiler and Typical Central Heating System

    Typical Central Heating System

Energy Savings Tips for the Home

In this series, you will find some energy savings tips for the home that will also end up saving you money in the long run. You will learn about better insulation for your home's roof and walls, draft-proof windows and doors, hot water tanks, and more efficient central heating systems.
  1. Energy Efficient Fixes for Your House Reduces Carbon Footprint
  2. High Efficiency Central Heating System Components - Condensing Boilers and Programmable Timers
  3. Improve Your Home Heating Using Energy Efficient Heating System Components
  4. Recycling and Reuse of Old Hot Air Central Heating Systems
  5. Save Energy for Your Home - Take the Survey