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What is the Vacuum Sprinkler System?

The Vacuum Sprinkler System is a sprinkler system in which the interior of the pipes constituting the ducting network is kept under vacuum. In other words, the air contained in the network is at a lower pressure relative to the atmospheric pressure of the installation site.

(See: What are the benefits of Vacuum Sprinkler Systems?)

Why do we say that these Sprinkler Systems are in a "vacuum"?

The term “Vacuum” is commonly used to designate the partial removal of air from a closed space and its isolation from its environment. In Vacuum Sprinkler Technology, the removal of 20% of the air initially contained inside the Sprinkler Networks is sufficient to obtain its benefits.

(See: What are the benefits of Vacuum Sprinkler Systems?)

What are the benefits of Vacuum Sprinkler Systems?

The benefits of using a vacuum, listed below, are numerous, and they offer increased reliability and a longer service life for Sprinkler Systems.

Yet to profit from the benefits of this new technology, the vacuum systems must be installed in compliance with the applicable rules and regulations: installation regulations, rules of the art, and the specific rules for vacuum systems.

The benefits that make the system reliable, cost-effective, ecological and durable:

  • Standard* installation equipment and components, except:
    • Control unit: vacuum sprinkler control unit
    • Sprinklers: sprinklers operating in a vacuum
  • Fast and easy deployment and operation, with low energy consumption.
  • Cheaper maintenance and operation.
  • Fast activation of the system: < 5 seconds.
  • Dry system: no water + natural drying of pipes when on standby:
    • Little/no corrosion, development of microorganisms, and hence of sludge build-up and system clogging.
    • No need for internal treatment of the pipes.
    • Possibility of using black steel (with factor C-120).
    • No frost risks.
    • No need for antifreeze (glycol, etc.).
    • No need for heating.
    • No leaks from sprinkler network into the external environment (potentially contaminating other systems).
    • Required water density for discharge.
    • No need to use drinking water, the following water sources can be used**:
      • river,
      • rain,
      • recycled,
  • No pressurised air:
    • No condensation, which would increase the corrosion phenomenon and frost risk.
    • No air blown over the zone where the sprinklers are activated.
    • Fast-arriving, full-jet water spray.
  • Conversion of existing traditional sprinkler systems into a vacuum sprinkler system.

* Elbow bends, T-bends, steel pipes, eccentric reducers, valves, etc., complying with the various rules applicable to vacuum systems.
** The pipes that are upstream of the sprinkler network, and which are wet, must be adapted to the water source used.

Note: quantifying the benefits of the application of Vacuum Technology will depend on the project itself; you should therefore contact Vactec or its Representatives to assess the gains to be made and the conditions for attaining them.

What are the differences between "Vacuum" and "Dry" sprinkler systems?

The difference is the air pressure when on standby.

The dry system is permanently under positive air pressure (above atmospheric pressure), whereas the vacuum system is under negative pressure (below atmospheric pressure).

It is this pressure inversion that gives the vacuum system its many advantages over the dry system.

(See: What are the benefits of Vacuum Sprinkler Systems?)

Do vacuum sprinkler systems cost more than traditional sprinkler systems?

This question can only be answered case-by-case. The specific equipment for Vacuum Sprinkler Technology, in particular the Vacuum Control Unit, does cost more than a Wet or Dry Control Unit (water valve or air valve). However, Vacuum Technology offers many benefits that can reduce:

  • the pipe network costs, particularly compared to Dry Systems (use of black steel; mesh/loop configurations possible, reducing the overall cost of the pipes for identical sprinkler flow, etc.);
  • the number of pipe networks required for covering a risk zone, compared to a dry system;
  • the cost of purchasing, installing and using anticorrosion (in particular nitrogen generation), antibacterial or antifreeze systems;
  • the investment or operating costs in infrastructures for preventing frost (buildings insulation, boilers, fuel, etc.);
  • operating losses due to the pollution caused by traditional sprinkler systems into their environment, or due to its remediation;
  • the operating / maintenance costs, including the costs of personnel carrying out these tasks.

The global budget for these costs can make the Vacuum Sprinkler System economically attractive right from the time of installation or after a depreciation period (considering the Total Cost of Ownership).

Are Vacuum Sprinkler Systems certified?

Yes. They are certified by the North American body, FM (FMA: Factory Mutual Approvals), and the European ANPI.

What types (models) of sprinkler need to be installed in a Vacuum Sprinkler System?

Sprinklers certified for “Vacuum” operations need to be installed. The list of Vacuum Sprinkler models can be obtained by contacting us directly, or you can refer to the technical data sheets of the manufacturers.

NB: Aside from this specific requirement, “Vacuum” sprinklers present the same characteristics (opening (K-factor), mechanical mounting, reaction time, etc.) as traditional sprinklers.

Can I insure my Vacuum Sprinkler installation?

Yes, it is a certified Vacuum Sprinkler System.

Can I install a Vacuum Sprinkler System?

Yes, since the system is certified.

Who do I contact if I want to protect my property with a Vacuum Sprinkler System?

Vactec, its partners, or its Representatives.

Are Vacuum Sprinkler Systems also an alternative to Wet Sprinkler Systems?

Yes, thanks to the preaction operating mode.

How does the Vacuum Sprinkler System fight fires? Is it the Vacuum that fights the fire?

The vacuum system fights fire in the same way as traditional systems, by spraying an extinguishing agent, generally water, through the opened sprinkler(s).

No, it is not the vacuum that fights the fire. The vacuum is only present during standby, and is replaced very rapidly by the extinguishing agent when the system is activated.

Can a fire detection system be linked up to a Vacuum Sprinkler System?

Yes, Vacuum Sprinkler Systems can be controlled by external detection systems. This means that all operating modes are possible (Non-Interlock, Simple Interlock, Double Interlock) and included in the Vacuum Sprinkler Systems Certification.

Can an existing Traditional Sprinkler System be used, and transformed into a Vacuum Sprinkler System?

Yes, a Vacuum Sprinkler System is first and foremost a Sprinkler System, and reuses the same principles and the same pipe networks for its operation. It will be necessary to check the compliance of the entire sprinkler installation against the regulations in force and the specific regulations for vacuum systems, then to install a Vacuum Control Unit (containing the vacuum pump) and specific sprinklers. Engineering calculations are needed to validate the performance of the Vacuum Sprinkler System components as a whole, including the water source, and their suitability for the covered risk.

Vactec has already converted existing wet and dry installations into vacuum sprinkler systems, retaining most or all of the pre-existing networks and water sources, and thereby making significant savings for its customers.

Do preaction operating modes exist in vacuum technology?

Yes, vacuum systems can operate in preaction mode:

  • non-interlock
  • single interlock
  • double interlock

(See: Can a fire detection system be linked up to a Vacuum Sprinkler System?)