The crucial differences in vented and sealed systems
The crucial differences in vented and sealed systems
Nowadays there is a choice of heating boiler forms to drive your central heating system according to your family requirements. Below you will find an outline of the main variants of central heating system currently traded. The main component in a central heating system is the gas boiler and this will be selected in accord with your needs.
In northern Europe the main household system will be the heating system, although there is much talk of world-wide warming at the moment there is little mass demand for air conditioning systems. Whether you are looking at a completely new dwelling house or an established house one of the characteristics you will need to investigate is its central heating system.
Whilst we tend to forget about the central heating system it will be functioning everyday to supply hot water and comes to the fore in the wintertime when heating your dwelling house. Heating your dwelling house provides a relaxing and cosy atmosphere. In addition to warming the dwelling the central heating system will be used to supply hot water when required. For these reasons your central heating system has to be reliable. Out of sight everyday operation without unforeseen breakdowns is a standard requirement of any central heating system.
Whilst there are many forms the two primary forms of system are vented and sealed systems.
pumped/vented systems are the most usual. You will notice that this configuration incorporates a feed and expansion tank in addition to a hot water cylinder. Hot water expands and in this type of system flows back to the expansion tank. If you look for the expansion tank in an existing system you will most commonly find it in the attic.
A more modern alternative is a sealed system. Sealed systems have less components having no need for the water expansion tank. A sealed Central Heating System is connected to the mains water supply to allow the removal of the water feed tank. There are no tanks or copper piping in the attic, you get a range of advantages from the elimination of these components:
- no chance of freezing pipes in the attic
- fewer parts mean reduced purchase costs
- fewer leaks from pipe work joints
- the sealing of the system precludes air entering which could lead to inner corroding or the evolution of an air lock
Normal variations of pressure can be allowed in a sealed system through a pressure vessel that holds compressed gas. Safety valves open if the internal pressure is too high. Other automated valves open to allow the interior water to be topped up if it drops to low.