Placing water-based fire retardants in areas with electronics, archives, art and other high-value goods was a major worry… until now.


Gemini allows the use of sprinklers in areas where accidental release would cause damage. Unintentional activation of the system (by accidental mechanical damage of the sprinkler, for example) is very unlikely but, unfortunately cannot be ignored. This is one of the reasons why, until now, sprinkler systems have seldom been used in particularly sensitive areas where an accidental release would cause significant damage.


Gemini is ideal for the use in the following areas:

  • IT and server rooms
  • Electronic control or monitoring set ups
  • Telecommunications facilities
  • Archives
  • Pharmaceutical plants
  • Art galleries
  • Museums


With this system, the quick response sprinkler heads operate in such a way that the first head to activate acts like a detector and will signal an alarm condition. The second integral head is engineered to act as a normal quick response sprinkler head and discharges water on activation of the bulb. The triumph of this engineering is that each Gemini device is a mini pre-action sprinkler system and the sprinkler heads are dual purpose, meaning that both of the integrated heads can operate as a detector before water is discharged. When activated as a result of an actual fire condition, the quick response heads allow water to quickly discharge at the seat of the fire, thus minimising any delay in fighting the fire and providing the benefits associated with wet systems and quick response low RTIs.


Gemini offers a number of environmental benefits; avoiding accidental discharge of sprinklers naturally prevents the associated waste of water. Also, water discharge is generally more environmentally friendly than the alternative gas systems available.


Many existing installations have gas as the extinguishing agent, however such systems are now regarded as being non-environmentally friendly and have deadlines looming for halon replacement. It is timely that a new, exciting, patented and approved pre-action sprinkler head has been launched.


Pre-action Sprinkler Head

With this system, the water will not be discharged before both of the sprinklers are activated as their direct side-by-side arrangement forms a common safe unit. Generally, both of them will only open at the corresponding fire characteristics.


The risk of an accidental release can be almost eliminated using this detector-controlled pre-action system.



  • No accidental damage
  • Helps combat malicious damage
  • No expensive refills like gaseous systems
  • Effective risk management
  • Environmentally friendly
  • Low maintenance costs
  • Reliable protection
  • Efficient installation process



Gemini prevents the accidental release of water, potentially saving considerable amounts of water wastage. Gemini also provides an excellent level of fire protection which reduces the risk of extensive damage. Together, these benefits reduce energy consumption and overall costs.

Gemini offers considerable benefits over gas systems including a substantially reduced carbon footprint. Unlike gas systems, Gemini requires minimal maintenance which further reduces the carbon footprint associated with maintaining protection levels.


How it Works



On release of the right sprinkler (1), the float is no longer supported by the spring-loaded spacer piece and will drop down to operate a switch contact. The Gemini sprinkler still remains closed against the pipe system and no water will be discharged.

On release of the left sprinkler (2), the top sealing cone and the distance pipe are no longer supported by the glass bulb. The water enters the Gemini sprinkler and causes the float to move up, thus operating the switch contact. At the same time, the bottom sealing cone of the distance pipe closes so that no water can be discharged. In both cases, the switching contact transmits a signal to the sprinkler monitoring system DSZ 3000 or by a connected fire detection control panel. The alarm signal can also be transmitted to any remote or external location.

On activation of both sprinklers (3), the water is discharged through the right sprinkler head.


The Gemini sprinkler will not discharge any water until both heads have operated. The first head to open releases an electronic signal to the supplied control panel (DSZ 3000) or to a suitable connected fire detection control panel, but discharges no water. Water will only be discharged if the second head opens.


Technical Details

Operating Pressure   Water 10 bar (145 psi) maximum
Type of Sprinkler    15mm Spray Sprinkler
Operating Voltage   1~230v 50Hz
Release Temperature   68ºC
K-Factor   57
RTI   35-50
Protection Area   9m2
Approvals   VdS



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Click here to see our FAQs regarding Gemini.



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We are always happy to discuss our extensive range of innovative solutions. Contact us on +44 (0)1889 271 271. Or if you would like to email us please use our contact form.

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