4
400E-DP-Y
2.2
System Air-Pressure Requirements
The system shall maintain a pneumatic pressure between
2.4-2.
6 barg (36-38 psig), requiring a dry, clean,
dependable and continuous compressed-air source using an Air Maintenance Device which includes a pressure
regulator, restriction orifice and a ½” normally closed by-pass valve, the Air Maintenance Device should be
provided with a downstream pressure gauge to indicate system pressure.
A dry nitrogen-gas can be an alternative for air pressure system.
NOTE
: In refrigerated areas, the supply air dew point must be maintained below the lowest temperature to which
the Dry piping might be exposed. Introducing moisture into system piping exposed to freezing temperatures can
create ice blockage, which could interfere with the system's correct operation. At the least, the air supply should be
taken from refrigerated areas at the lowest system temperature. The air supply must be carefully regulated to
prevent clogging by frost deposits.
2.3
Temperature Considerations
The Water Control Valve, all interconnecting water piping and trim components must be installed in an accessible,
clearly visible area maintained at a minimum temperature of 4
˚
C.
NOTE:
The Water Control Valve must be installed only in areas where it will not be subjected to freezing
temperatures. No heat tracing is allowable for the Water Control Valve or for interconnecting piping. Avoid
situations in which the dry sprinkler network is exposed to extreme temperature variations. A rise in the
temperature of the compressed air might increase pressure to more than that recommended.
3.
Operations
The Bermad Dry-Pipe Control Valve is best suited for automatic dry sprinkler systems. Dry-Pipe Valves are defined
as systems that admit water to sprinkler piping only upon operation of automatic sprinkler and/or pneumatic
pressure drop in the system-piping network. The sprinkler piping is automatically supervised.
The system includes a Bermad Water Control Valve with Dry-Pipe Control Trim, attached to dry sprinkler-piping
system with automatic sprinklers.
The Bermad Water Control Valve remains locked by water trapped in the control chamber. The closed valve
prevents unintentional water flow into the sprinkler-system piping.
To flow water into the sprinkler piping, the
URV
-M (U) air pressure operated valve must be activated by the loss of
pneumatic system pressure due to sprinkler operation and pneumatic release, causing the Bermad Water Control
Valve to open and allow water flow into the piping system, the URV-M (U) prevents line-pressure from entering the
control chamber, latching the main valve open and allowing water to flow into the system piping and to the alarm
devices.
The Dry-Pipe Valves are mostly used where sprinkler piping may be exposed to freezing temperatures.
Warning
: Whenever the Manual Emergency Release (15B) is activated, the Water Control Valve will open allows
water to flow into the sprinkler piping system.
NOTE:
The Valve must be installed where it will not be subjected to freezing temperatures, when installed in
freezing conditions the FP 400E-DP must be located in a heated structure and air supply must be dried in order to
prevent from water residuals and humidity from freezing within the system and piping.
