When the water in a pressurised system expands the pressure in the.
Unvented central heating system diagram.
S plan heating systems are now the most common type of system installed in the uk after combination boiler systems which do not have any external motorised valves.
Instantaneous hot water heating systems this method involves using gas or electricity to heat the water to a useable temperature without the need to store the water.
Hamworthy s upton condensing boilers and stratton mk2 wall hung boilers are suitable for installation in sealed heating systems only.
The s plan is popular because it is versatile you can add an unlimited number of zones simple to wire and easy to fault find on.
A guide to the most common types of domestic heating and hot water systems with diagrams including indirect boiler system unvented system thermal store.
The diagram below shows the general layout of an unvented hot water system.
The arrangement shown here is most likely for an existing y plan system where the cylinder is being changed to an unvented one.
A guide to the different ways of heating domestic hot water so you can identify problems and faults with the hot water tank or central heating system and carry out any maintenance needed.
Modern heating systems run by gas boilers tend to be unvented or pressurised.
However our purewell variheat cast iron condensing boiler can be installed in an open heating system.
In an unvented system there is no header tank and the water in the pipes is under pressure.
For an entirely new installation s plan would be a far better choice as that does not have the default open problem and also allows the use of multiple zones for the central heating.