There are several different types of domestic boilers on the market, and which one you choose depends on both your heating requirements and your budget. Before we look at the different types of boilers available, we should point out that Gas Boilers must be installed by a Corgi registered installer (and they should have relevant and up-to-date public liability insurance).
If you are having a new domestic boiler installed, you need to make sure that it is powerful enough for the amount of radiators in your house, as well as the hot water cylinder. If you are having the boiler installed, the heating engineer you plan to use should be able to advise you. If he/she cannot, you can work out your power requirements yourself. To do this, check the manufacturers specified heat output for all the radiators in you house and add the figures up. Now add a 3kW allowance for the hot water cylinder and you have your minimum power requirement.
Ideal Room Temperatures
If you are having a central heating system installed, your heating engineer will try to provide a system which can heat your rooms to certain temperatures. The temperatures below are the average or ideal temperatures for the rooms in your house. However, there is no real reason why you can’t plan to have a much warmer or cooler house.
Bathroom – 23c (72f)
Dining Room – 21c (70f)
Living Room – 21c (70f)
Hallways – 18c (65f)
Bedroom – 16c (60f)
kitchen – 16c (60f)
Gas-fired boilers are probably the most common type in the UK and there are models to suit all budgets and heating requirements. Most Gas-fired boilers have a pilot light which is always lit, ready to light the burners at the flick of a switch. Gas-fired boilers can be manually operated or set on a timer. You can also link the boiler to thermostats in each room so that a constant temperature can be maintained. Some newer gas-fired boilers will have an electric ignition, which removes the need for a pilot light.
Oil-fired boilers work in a similar way to gas-fired boiler and have very similar controls. As with gas-fired boilers, modern oil-fired boilers will be condensing boilers, making them much more efficient. In general, this type of boiler will initially be more expensive than a similar gas-fired boiler, but could offer better fuel efficiency over time. The other benefit of an oil-fired boiler is that it does not need to be connected to a mains supply. You will need to have an oil tank installed in an area of your garden which is easily acessible, but this could be a good option for rural or remote properties with limited or difficult access to the mains gas supply.
Solid-fuel boilers are much less common than the two examples above, but can still be found in homes across the country. Solid-fuel boilers differ from gas and oil-fired boilers in that they do not provide instant heat and must be “fed” with a solid Anthracite fuel or other smokeless fuel. In some cases, solid-fuel boilers will not need an electricity supply for ignition, meaning hot water and heating can still be maintained during a power cut. Solid-fuel boilers are available in two basic types: gravity fed and batch fed.
Combination boilers can provide hot water for the heating system and a separate supply for taps and showers. Combination boilers heat the water as it is needed from the mains supply, meaning that you do not need a hot water cylinder or a storage tank in the loft. This makes them ideal for small house and flats but as the flow rate is fairly slow and often you will not be able to run two hot taps at once, may not be suitable for a family home. However, as they are easy to install and you only heat the water you need, combination boilers are often one of the cheapest options available.
By law, all new domestic boilers fitted in the UK must now be condensing boilers (except in some exceptional circumstances). Condensing boilers are up to 90% efficient, compared to non-condensing boilers which could be only 60 or 70% efficient, meaning that they save both energy and money. Condensing boilers work by using a large heat exchanger to make the best possible use of the heat from the burners, which also reduces heat loss from the flue. They are available in regular and combination types and can usually be fitted to an existing heating system without too much trouble.