4-2.3.5.1 Limits On Nozzle Conditions; 4-2.3.5.2 Maximum Elevation Differences In Pipe Runs - Kidde Fire Systems ECS Manual

• 180° Nozzles-180° nozzles must be located 12 +/- 2 inches (0.3 +/- 0.05 m) from a wall,
with the orifices directed away from the wall. The nozzle shall be located as close to the
center of the wall as possible, but at least 1/3 of the way along the wall.
180° nozzles have a maximum coverage area defined as any rectangle that can be in-
scribed in a semicircle of distance 48.3 ft (14.73 m, diagonal of a rectangle 20' x 44'). Refer
to Figure 4-3 for further information.
180° nozzles may be used in a back-to-back configuration. The nozzles should be place 1
to 2 ft (0.3 m to 0.6 m) apart.
• 360° Nozzles-360° nozzles must be located as close to the center of the enclosure as pos-
sible. 360° nozzles have a maximum coverage area defined as any rectangle that can be
inscribed in a circle of radius 29.7 ft (9.06 m, diagonal of a rectangle 20' x 22'). Refer to
Figure 4-3 for further information.
• Multiple Nozzles-Nozzles whose discharge patterns will intersect must be placed at least
10 ft (3.05 m) apart to assure adequate agent distribution.
• Walls and Obstructions-HFC-227ea discharged from the nozzle requires a certain length
from the nozzle to atomize into a gas. If the HFC-227ea comes into contact with a surface
before the agent is fully atomized, frosting can occur. As a result, the concentration
throughout the enclosure will be less than required to appropriately protect the space.
Therefore, nozzles must be located with at least four to six feet of clearance from walls
and/or significant obstructions (ex. high rise racking and columns). If this requirement can-
not be met, additional agent may be discharged to compensate for this agent "loss".
• Reduced Coverage Area-Consideration should be given to reducing nozzle spacing when
obstructions that would impede the uniform distribution of HFC-227ea throughout the area
are present. Nozzle coverage area must be reduced to 25 ft x 25 ft for enclosure heights
six to twelve inches (7.5 m x 7.5 m for heights 0.15 to 0.3 meters).

4-2.3.5.1 Limits on Nozzle Conditions

• Minimum average nozzle pressure-The nozzle pressure must be a minimum of 74 PSIG
for the nozzle to effectively disperse the agent and mix the agent into the air of the enclo-
sure being protected.
• Maximum arrival time imbalance-The difference between liquid arrival times at two of
the nozzles must not exceed the 0.8 seconds allowed maximum.
• Maximum run-out time imbalance-The difference between nozzle liquid runout times at
two of the nozzles must not exceed the 2.0 second allowed maximum.

4-2.3.5.2 Maximum Elevation Differences in Pipe Runs:

• If nozzles are only located above the container outlet, then the maximum elevation differ-
ence between the container outlet and the furthest horizontal pipe run or discharge nozzle
(whichever is furthest) shall not exceed 30 ft (9 m).
• If nozzles are only located below the container outlet, then the maximum elevation differ-
ence between the container outlet and the furthest horizontal pipe run or discharge nozzle
(whichever is furthest) shall not exceed 30 ft (9 m).
• If nozzles are located both above and below the container outlet, then the maximum ele-
vation difference between the furthest horizontal pipe runs or discharge nozzles (whichever
is furthest) shall not exceed 30 ft (9 m).
Note: If you have a system design that violates these limits, the factory must be consulted to
determine what course of action should be taken. See Figure 4-4 for further clarifica-
tion.
06-236115-001 4-13
Design and Installation
October 2014