DIY Projects - Central heating systems
Central heating is one of the most popular forms of heating in our homes. It consists of a boiler which heats the water, this is then pumped to the radiators or convector heaters where the heat is released into the rooms. The water then returns back to the boiler for re-heating.
Some central heating systems also circulate hot water through a coil in the hot water cylinder which in turn heats the domestic hot water which comes from our taps.
The boiler is the main component of a central heating system and can come in many forms, they can use gas, oil or solid fuel. The most common is gas due to the availability and ease of use. In rural areas where there is no mains gas, bottled gas can be used.
Oil fired boilers again are mainly used in rural areas where there is no mains gas, but an oil storage tank and access for tankers is necessary.
Solid fuel boilers are the least popular mainly due to the dirt and inconvenience of solid fuel, also a separate heater such as an immersion is necessary for summer when the solid fuel heater will not be being used.
Typical temperatures in the average house
DIY Projects - Central heating controls
Programmers
The control of central heating is extremely flexible, there are programmers which turn either the hot water and central heating on at set times. These can be the simple dial type with 2 on and off settings, which is repeated each day or there are the all singing all dancing digital programmers that can have 6 on and off settings which can be set for different times every day. |
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Thermostats
There are thermostats that can be room based (room stat) or fitted directly to the radiators (thermostatic radiator valve, or TRV) and there are cylinder stats. By using a combination of thermostats, running costs can be reduced by not using gas unnecessary and also reducing the wear and tear of the boiler and pump etc.
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Digital Room StatA roomstat is all that is needed to control the central heating system, when the stat determines the room needs warming, it will fire up the central heating boiler, or in the case where the boiler is already on heating the hot water, the roomstat will open a valve to let the water circulate around the radiators. The main drawback is the temperature of other rooms cannot be controlled accurately. |
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Thermostatic Radiator Valve (TRV)These are fitted directly on to the radiator in place of a normal radiator valve and control each radiator independently. You do not need to fit TRV's on every radiator, it is normal to use a combination of TRV's in conjunction with a room stat. Fit the TRV's to radiators in south facing rooms where the sun will also heat the room and let the room stat control the temperature throughout the rest of the property. |
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Cylinder StatThese are fitted directly onto the hot water storage cylinder and depending on the type of installation can shut a valve or turn the boiler off, providing it is not heating the radiators. |
Zone Valves
Zone valves can be used to isolate entire areas, such as shutting off the bedroom radiators during the day. This can reduce running costs considerably.