Sprinkler systems are self-acting fire extinguishing systems having an uncomplicated as well a safe functioning principle. A network of piping and sprinkler heads are installed throughout the areas of the building requiring protection and is constantly under pressure. Under normal conditions the sprinkler head is closed off by a liquid-filled bulb. If due to the effects of a fire, the ambient temperature in the immediate vicinity rises by approximately 30 c° above the maximum temperature expected under normal conditions, the glass bulb bursts. Then pressurized extinguishing water flows through the piping into the sprinkler head and the resulting water jet hits the spray plate which diverts the spray to the areas to be covered. At the same time the water flow in the piping network trips the alarm systems. When the fire is extinguished, replace the activated sprinkler that was activated and the system is ready for operation again.