What is the Tundish, and what’s it’s purpose?

The Tundish is a really important part of the installation. It serves as an air break, AND a visual alarm that something’s wrong with the unit, or system.

The cylinder is a potential bomb, so in the event the cylinder controls fail, ALL of them that is (highly unlikely), the cylinder has emergency discharge valves, that open to release excessive high pressure that could build up inside the unit in fault conditions.

These valves have to be connected to a discharge pipe, which has specific criteria to which it has to be installed. This is to ensure that superheated high pressure water and steam can discharge to a safe termination point.

This pipe has to be resistant to high temperature, and pressure. Therefore, it is usually installed using metal pipe (copper) or an approved high temperature resin/PVC pipe.

Pressure Relief Valve

Tundish

Temperature & Pressure Relief Valve

Approved trap, connected to the discharge pipework

This is a close up of a Tundish in fault condition.

The idea of being open, is so you can see when water is running through the discharge..

This indicates a fault, and the unit requires servicing, or a repair..

A selection of Tundishes, take a look at yours.

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Updated 02/08/12