| You will already have a heating system in your | | | | size system. If you have improved the insulation |
| home (80% of homes in Britain have central | | | | as indicated then it is likely that the system will be |
| heating or storage radiators). Most of these | | | | oversized and the boiler size can be reduced |
| systems have been designed to cope with the | | | | when you next replace it. You may also want to |
| higher heating load of a badly draught-proofed and | | | | reduce the size or number of the radiators if this |
| insulated house. Many of them have the capacity | | | | will enable the more efficient use of any of your |
| to heat the house on the coldest day of the year | | | | rooms. |
| to 21 °C and it is arguable that this is | | | | If you don't have central heating, you may well |
| necessary. Many heating systems work most | | | | be considering whether it is right for you. You |
| efficiently when they are working at maximum | | | | need to make a realistic assessment of the costs |
| load, which means that if the system is designed | | | | of your existing system. For example, you may |
| for the coldest day it will be working less | | | | have individual heaters using existing chimney flues |
| efficiently on all the other days. This problem is | | | | which could be resulting in considerable heat loss. |
| being solved with the latest designs of boilers and | | | | If you have a relatively large house and you need |
| their controls. | | | | to keep the majority of it warm most of the |
| Since we are looking at the ecological upgrading of | | | | time, it is probably sensible to go for a |
| an existing system we need to review the | | | | high-efficiency gas central heating system and for |
| situation with the assumption that you have | | | | the smallest boiler size compatible with the |
| draught-proofed and insulated your home to as | | | | insulation. |
| high a standard as you can afford. The most | | | | A partial central heating system |
| ecological sources of energy have already been | | | | If however you have a medium-sized two-story |
| identified. The best system for your particular | | | | well insulated house, it is certainly not essential to |
| home will depend on the characteristics of the | | | | install full central heating in order to ensure an |
| building and your lifestyle. The alternative systems | | | | adequate distribution of heat. Evidence suggests |
| to choose from are as follows:o Full central | | | | that if the ground floor is kept warm through |
| heatingo Partial central heatingo Individual space | | | | central heating, sufficient heat finds its way |
| heaters where requiredo Reliance entirely on | | | | upstairs by natural air movement upwards, |
| incidental sources of heat | | | | encouraged by the stack effect and conduction |
| There are various reasons why you may not | | | | through the ground floor ceilings to provide an |
| require a full central heating system. Here are | | | | acceptable temperature in upstairs bedrooms. |
| some of them:o If your house is small, compact | | | | Even if you have central heating, it is probably a |
| and well insulatedo If your house receives | | | | good idea to place a heater with some radiant |
| sufficient passive solar energyo If your house has | | | | output in the main living room to allow a quick |
| an Aga or equivalent rangeo If your house has a | | | | warm-up of the principal room. It is useful in |
| large ceramic masonry heatero If you intend to | | | | autumn and spring to be able to warm one room |
| concentrate your activities in only one or two | | | | without having the whole system running. |
| rooms | | | | Individual space heaters and alternatives to central |
| We shall start by looking at full central heating, | | | | heating |
| and work back from there. | | | | There are many different types of unit space |
| Full central heating | | | | heaters. Some of the most efficient now are the |
| The vast majority of central heating systems use | | | | gas wall heaters with balanced flues. There is also |
| water as the medium to transport the heat from | | | | the possibility of an efficiently designed |
| the central boiler to where it is required. There | | | | wood-burning stove, if you are willing to spend the |
| are many other types of central heating such as | | | | time tending it to ensure that it burns correctly. |
| hot air systems, underfloor heating and steam | | | | Many people have been persuaded into heating |
| systems. However I shall deal mainly with 'wet | | | | their homes with electric storage heaters because |
| systems' as it is the system you are most likely | | | | of cheap rate tariffs-which bear very little |
| to have. | | | | relationship to the amount of C02 produced-and |
| A wet central heating system consists in most | | | | the cheaper initial cost of installation. However, |
| cases of the following parts:o The boiler that | | | | heating your house wholly by electricity is not |
| burns the fuel and transfers the heat to watero | | | | ecologically sound and should certainly be avoided. |
| The pipework that transports the hot water | | | | Electric heaters can be justified only if they are |
| usually with the help of a pumpo The radiators | | | | used sparingly as a top-up heater to be taken on |
| that transfer the heat from the water to its | | | | occasion to anywhere in the house and used in a |
| surroundingso The controls to ensure that the | | | | very localised way for a limited period of time. |
| right amount of heat is delivered to where | | | | The most effective heaters for this purpose are |
| required at the right time | | | | the small fan heaters with built-in thermostatic |
| If central heating is already installed, the first | | | | control. However, think first of wearing more |
| question to ask is whether or not it is the right | | | | clothes! |