Is your heating system vented or sealed
Is your heating system vented or sealed
Central heating systems have developed and that there are now many different variants each with differing benefits and drawbacks according to your requirements. This document will help you to visualise the alternatives available to you. The primary alternatives are driven by central heating boiler type although this will influence the other system component parts.
Air conditioning systems are not yet a stock feature in households whereas every northern European family is built with a form of central heating. Virtually all new housing developments incorporate central heating systems as a stock fixture within the family.
Try running a family without your central heating system switched on and you will quickly understand how important the system is. Heating your household provides a relaxing and cosy atmosphere. Another important role for the central heating system is to create hot water. For these reasons your central heating system has to be reliable. Systems tend to last for fifteen years and you will need one that is both efficient and reliable.
Whilst there are multiple varieties the two primary types of system are vented and sealed systems.
The most common type is a pumped/vented system. This type of system has a feed and expansion tank in concert with a hot water cylinder. The tank makes way for any water expansion that is caused by the heating process. The loft is most commonly used to house the expansion tank as it needs to be high in the house.
A more modern alternative is a sealed system. An advantage of a sealed system is that it has no demand for an expansion tank. The role of the water feed tank is now provided by the cold water mains. if you take this system you don’t need to use your loft for housing in the expansion tank thereby saving space, seaing the system and removing the need to vent the hot water has some benefits:
- as the pipe work is removed from the attic it will not be in danger of freezing in the winter
- no upkeep work on the tank or pipe work that would be in the loft in a pumped or vented system
- fewer leakages from piping joints
- as the system is sealed there is less chance of air incoming leading to corrosion or airlocks
Typical variations of pressure can be permitted 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 internal water to be topped up if it drops to low.