Design and installation guide
Pre-action sprinkler system: selection and application guide
A preaction system coordinates detection with admission of water to the sprinkler piping through the selected interlock arrangement. Single- and double-interlock options have different release conditions; select the arrangement for the protected space and operating scenario.
A pre-action sprinkler system controls water admission to the pipe network through the selected interlock arrangement. In a single-interlock system, fire detection opens the valve; a double-interlock system requires both detection and the pressure loss associated with sprinkler operation. Water discharges through open sprinklers. Select the arrangement for the risk and operating scenario of the data centre, museum, archive or sensitive-equipment space.
01
Operating arrangement and engineering
Selection considers the product function, the protected risk and operating conditions together. These steps support the site survey and quotation.
Interlock and detection scenario
Define detection signals, pipe-pressure supervision and valve-opening conditions from the selected system diagram. Do not assume one activation sequence for every preaction system.
Supervision and operational coordination
Supervise the panel, valve, air supply and impairment states. Plan loss of protection during maintenance and restoration with the operating team.
Hydraulic calculations and layout
Calculate hazard classification, storage or process data, pipe sizes and water demand at the critical point together. Pump, tank and head/nozzle selection are elements of this design.
Testing and maintenance
Verify water supply, valve/alarm functions and the relevant system scenario during commissioning. Record system-specific testing and maintenance tasks in operating records.
02
Applications and site planning
These examples show why placement and equipment requirements can differ between facilities using the same product.
Sensitive equipment spaces
- Site requirement
- Operational consequences of unintended water discharge.
- Application approach
- Assess fire risk, detection design and water-delivery needs together.
Spaces requiring coordinated operation
- Site requirement
- Alarm confirmation and maintenance supervision needs.
- Application approach
- Connect interlock conditions to a written cause-and-effect scenario and function testing.
03
Pre-quotation checklist
Scroll the table horizontally to view every column.
| Check item | Product / application | Information to assess |
|---|---|---|
| System arrangement | Water admission through the selected interlock | Design diagram and operating scenario |
| Water supply | Pump, tank and pipe network | Hydraulic demand and available supply |
| Space | Fire hazard and environmental conditions | Storage, temperature and obstructions |
| Handover and maintenance | Function tests and records | System-specific inspection plan |
Select the sprinkler arrangement through a combined assessment of hazard, environment and water supply. Survey and engineering calculations establish its layout, equipment and operating scope.