Shut-off Valve Increases Water Main Pressure for Firefighting

July 2011 – Danfoss, manufacturer of industrial control components and systems, had a solution when new construction regulations for controlling water mains pressure in the event of a fire were introduced in Poland in 2006. Now, the high water pressure necessary for fighting fires never fails.

Danfoss EV220B Water supply and distribution lines for residential, commercial and industrial facilities are made of plastic leaving the pipes likely to melt in the event of a fire. 

If a fire hydrant installation shares the same water piping network, any heat damage to the pipes will cause a drop in water pressure – and water pressure is crucial for effective firefighting.

In Poland, construction regulations introduced in 2006 stipulate that there must be a way of securing water mains pressure in the event of a fire – so Danfoss’ team in Poland came up with a solution.

The Right Pressure and Flow Rates
When the new regulation was introduced, the team at Danfoss Poland was quick to realize that the EV220B solenoid valve, particularly the bigger DN65-DN100 flanged versions, would be ideal as a firefighting shut-off valve. The team created an application note, explaining the new regulations and the valve specifications, which they sent to design offices throughout the country. Ideal for robust industrial applications demanding high flow rates, the EV220B has a cast iron valve body, a built-in pilot filter, a flanged connection and a working pressure up to 10 bar. 

Danfoss EV220B How Does it Work? 

A building’s water supply is normally divided into two sections: one for general every day use, on which the EV220B is mounted, and the other for the hydrant line. 

In the event of a fire, the EV220B shuts off the internal water distribution system, ensuring that all water flows to the hydrant.
The valve can be closed in three different ways: manually via a remote switch, automatically by means of an output from the firefighting system, if such a system is installed, or by means of a Danfoss pressure switch, which detects a pressure drop in the firefighting line when the firefighters open the hydrant.

Danfoss’ efforts caught the attention of design offices and construction companies throughout Poland and from 2006 to 2010, sales of the EV220B DN65-100 increased fivefold. 

For more information, please visit

Danfoss LLC
Industrial Automation
11655 Crossroads Circle
Baltimore, MD 21220

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