Schematic Unvented Heating System

These are over pressurisation and overheating.

Schematic unvented heating system.

An automatic bypass valve is fitted inside most combi boilers by the manufacturer these days. Regardless of the central heating design the sundial plan is a system that controls the boilers operating periods and temperatures for space heating and or hot water. There are three types of domestic hot water system. This first is a combi boiler system where the boiler directly heats the water on demand.

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. A guide to the most common types of domestic heating and hot water systems with diagrams including indirect boiler system unvented system thermal store. Before we look at the more technical aspects of the megaflo unvented boiler system which some incorrectly call the megaflow system or megaflow boiler instead let s take a look at the basics. One givaway is that there is often a pressure gauge on the boiler measured in bar.

Visit the unvented cylinder page on our interactive house for comprehensive information on unvented hot water systems. Modern heating systems run by gas boilers tend to be unvented or pressurised. Unvented hot water systems. The diagram below shows the general layout of an unvented hot water system.

In an unvented system there is no header tank and the water in the pipes is under pressure. Over pressurisation can be caused by a failed pressure reducing valve while overheating can occur if an unvented cylinder overheats and the water continues to increase in temperature and. This simply means the time the boiler starts up and for how long how much heat it provides for either space heating or for domestic hot water or both. 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.

The electric versions use a coiled heating element to heat the water rapidly in a. Megaflo or megaflow system. When the water in a pressurised system expands the pressure in the. 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.

No external pump no tanks no external expansion vessel no motorised valves and in many cases item 6 is not needed either. This is a system from the people over at heatrae sadia a highly recognisable and trustworthy name in the industry. Unvented systems have two basic dangers that must be addressed.