Understanding Your Heating System

Understanding Your Heating System


In a typical UK household, more than half the money spent on fuel bills goes towards providing heating & hot water. As fuel costs rise, having an efficient & cost effective system is vital, & it is one of the main steps you can take to reducing your carbon dioxide emissions.

It is important to understand your current heating system. Nearly all homes in the UK have either a central heating system - a boiler & radiators - or they use electric storage heaters. Some homes will also make use of individual heaters that are not the main central heating system.

Central Heating - This is the most common form of heating in the UK. A single boiler heats up water that is pumped through pipes to radiators throughout the house as well as providing hot water to the kitchen and bathroom taps.

Most boilers run on mains gas, but in areas where mains gas in not available, the boiler can run on oil, LPG (tank gas), coal or wood. Mains gas is usually the cheapest, & it has the lowest carbon dioxide emissions, apart from wood. Some boilers also have an electric immersion heater as a back up.

If you have a central heating system, you may consider these energy-saving improvements:

  • Replace your boiler with a newer, more efficient model
  • Fit better controls & use them to make sure your boiler only provides heat where & when you want it
  • Switch to a cheaper or lower carbon fuel or technology.
  • Make any insulation & draught-proofing improvements that you can
  • Use chemical inhibitors to help maintain central heating system efficiency

Type of boiler - Since 2005 virtually all gas boilers that have been fitted in the UK are more efficient, condensing boilers. Condensing boilers have bigger heat exchangers that recover more heat from the burning gas, making them more efficient. Your boiler will be a condensing boiler if the following points are true:

  • The flue is made of plastic. If it is made of metal, it is unlikely to be a condensing boiler
  • The boiler has a plastic pipe coming out of the bottom, through the wall & into the drain
  • It was installed after 2005 (if it is a gas boiler)
  • It was installed after 2007 (if it is an oil boiler)

Combi or Regular Boiler:

Combi Boilers - provide hot water directly, whenever it is required & it does not need a hot water cylinder. Gas, oil & LPG boilers may be combination.

Regular Boilers - provide hot water when the programmer tells it to, & then it stores it in a hot water cylinder until it is needed.

A regular boiler is more efficient that a combi boiler at producing hot water, but some heat is inevitably lost from the hot water cylinder, so overall a combi may be more efficient.

Electric Heating - Most UK homes that don't have a boiler & radiators, will have electric storage heater. These heat up overnight using cheaper off-peak electricity, & give out the heat during the day. If you have storage heaters, you will probably have a hot water cylinder heated up by one or two immersion heaters.

Electric storage heating is more common in flats, rented property, & in homes with no main gas connection. It is one of the most expensive heating options in the UK, and emits more carbon dioxide than most systems although in the future there are plans to de-carbonise the national grid reducing future electricity carbon dioxide emissions. It is also harder to control electric storage heaters than radiators, especially with older systems.

If you have a new system like this, you may consider these energy saving improvements:

  • Install new, more controllable storage heaters
  • Fit thermostats & controls to make you existing system more efficient
  • consider making insulation & draught-proofing improvements
  • Replace your system with an efficient boiler system

Secondary Heating -  Many households use individual heaters, such as portable electric heaters or fixed gas fires, in addition to their central heating. This is called 'secondary heating'. Modern central heating systems are usually more efficient than individual heaters, nut it can make sense to use an individual heater to heat one space for a limited time. This can help avoid over heating spaces that do not need to be heated, or are used infrequently. Secondary heating is typically provided by one or more of the following:

  • Portable electric heaters such as oil filled, convection, panel or fan heaters
  • Portable gas heaters that run on bottled has or paraffin
  • Portable halogen heaters
  • Wood burning or solid fuel stoves 
  • Open fires
  • Range cookers
  • Traditional gas fires
  • Wall-mounted gas heaters

Smaller portable heaters, such as fan & halogen heaters, can be useful if only a small room or area needs heating for a short period of time.

Where central heating does not heat the room enough, or there is no central heating in the room, electric convention, oil-filled or panel heaters might be a suitable option for providing the required level of heat. Electric heating is 100% efficient but electricity is expensive & carbon-intensive. If you do use an electric heater, make sure it is only on when needed.

Wood or other solid fuel burning stoves can provide adequate heating for a single room & are much more efficient than open fire & less carbon intensive.

Open fires often provide a nice atmosphere to a room but they are very inefficient. Most of the heat from open fires, go up the chimney rather than heating your room. When your fire is not being used, it will most likely be a source of draught in your home, so make sure you know how to draught-proof it.

Portable gas heaters run on butane (bottled gas) or paraffin (heating oil). These types of heaters require good ventilation as they release combustion gasses & water vapour that can build up in unventilated rooms potentially making damp problems worse.

Non-Standard Heating Systems - Radiators or storage heaters provide heating in the vast majority of houses in the UK. However, a number of alternative technologies can be used, or in addition to, including underfloor heating, solid fuel stoves, range cookers, open fires, electric fires & gas fires.

Finding An Installer - If you want to get a wood burning stove, the installation must comply with Building Regulations. HETAS is a government-recognised body which approves biomass appliances & services.

You can use HETAS to find a trained installer.

If you are installing or replacing a fixed (wall-mounted or otherwise) gas heater then you will need to use a Gas Safe Register installer.

Portable heaters can be bought from DIY, hardware, or home furnishings shops & do not need to be installed by a professional. You can take them home & use them when you need to.