How does a preaction sprinkler system work?
Preaction systems require a detection and release system. When activated by a detector, the valve opens, allowing water to flow into the system pipe and sounding an alarm. When the heat source activates a sprinkler, water flows through only the open sprinklers.
How does a preaction fire system work?
In a pre-action system the water supply is held back by a pre-action valve. This valve is connected to a supplemental detection system. Water will not enter the pipe until the detection system is activated. Once activated, the valve is released and allows water into the sprinkler piping.
What are the three basic categories of preaction sprinkler systems?
There are three different types of preaction systems, a non-interlock system, a single interlock system, and a double interlock system.
What happens when the sprinkler head in a preaction system accidentally opens?
However, anything else that opens a sprinkler head or breaks the pipe can also release water and cause needless and expensive water damage. These include: Damage from freezing. Accidental physical damage of the pipe or fittings.
How does a single interlock preaction system work?
Pre-action / Single or double interlock system
A single interlock system operates in a similar manner as the dry pipe system. This type of system has one event that must occur before water runs into the system; fire detection from a heat or smoke detector where the pre-action valve opens.
What is the difference between deluge and preaction?
Deluge Systems are normally used in special hazard installations where water must be applied to an entire area for protection. Pre-action Systems are used to protect areas where water damage from damaged sprinklers or piping must be avoided.
What is the difference between single and double interlock preaction systems?
A single interlock system is activated only upon the event of detection device activation. Two separate events must happen; sprinkler activation and detection device activation, before water is admitted into a double interlock system.
What is the primary advantage of a preaction sprinkler system?
The main advantage of pre-action systems is found in the two steps needed for water to release. Since both the pre-action valve and the individual sprinkler head must activate in order for water to be released, it minimizes the possibility of accidental discharge.
How does a double interlock preaction system work?
In a double interlock system the electric detection device has to be activated together with a fall in the maintained air pressure in the closed automatic sprinkler pipeline, as at least one sprinkler is activated by a heat source, before water will be released into the sprinkler piping.