Sprinkler Systems

Types of sprinkler systems

A & F Sprinklers have over 25 years’ experience in fire protection and sprinkler systems of all types, for all environments.

The most common forms of fire protection and sprinklers systems are:

Wet Pipe

The wet pipe is the most common type of sprinkler system. The wet pipe maintains a constant supply of water, and is held in the pipes above the sprinkler heads. The system is connected to a water supply to offer a continuous stream of water and discharge when exposed to heat from a fire.

The wet pipe sprinkler system is most commonly used in buildings with no risk of freezing to ensure that the water supply is not compromised.

This system is easy to install and has relatively low maintenance costs. It offers a high level of reliability which is important for systems which may be required to spend long periods of time inactivated.

Dry pipe

Dry pipe sprinkler systems are filled with pressurised air, with the water in this system held back by a control valve.

When the sprinkler’s detectors are alerted to a fire, the air pressure drops, causing the valve to open and water to enter the sprinkler to aid in fire protection.

Dry pipe sprinkler systems can be used in sub-zero temperatures, so are suitable for buildings without heating such as commercial freezers, garages and warehouses.


With a pre-action sprinkler, the pipes are filled with air and water is only let into the pipes when a detector such as a smoke detector is operated.

Most commonly used to protect items in buildings such as museums or libraries, where accidental automation could potentially cause irreparable damage to valuable collections.

The pre-action sprinkler is similar to the dry pipe system in that water is kept from the pipes via a pressurised air valve. However, for the pre-action sprinkler system to operate, they must first detect the fire (via heat sensors or smoke detectors), which then opens the pre-action valve, allowing water into the pipes. The system will then operate like a wet pipe sprinkler system.


With a deluge fire protection system, the pipes are filled with unpressurised air and the sprinkler heads are always open. Water is only let into the pipes when the system is activated, either by a fire alarm or smoke detector, or by a manual pull station which signals the deluge valve to open, allowing water to flow freely to the sprinklers.

However, unlike the dry pipe system, which activates the sprinklers directly above the hazard only, the deluge system opens all sprinkler nozzles.

The deluge sprinkler system is a preferred choice for locations with a particularly rapid fire hazard, or high volume of highly flammable contents.

Water mist

The low pressure water mist extinguishing system is based on sprinkler technology with a particularly low consumption of water, thus providing great benefits for building owners and operators.

The EconAqua system reduces the consumption of water by up to 85% compared to classic sprinkler systems. Similar in function and structure to a conventional sprinkler system makes the EconAqua system very simple to understand.

In addition, as the design and installation is similar to a conventional sprinkler system, the end-user will benefit from all the skills and experience of the licensed installer.

In addition to our range of fire protection services, we can also offer advice during the planning stage to ensure that you and your insurance company are satisfied with the final design to protect your investment. For more information, call A & F Sprinklers on 0845 505 1550.