Reliable PrePaK DDX-LP Instructions For Installation, Operation Care And Maintenance

Instructions for
Installation, Operation,
Care and Maintenance
Note: Photograph is for illustrative purposes only.
Reliable Automatic Sprinkler Co., Inc., 103 Fairview Park Drive, Elmsford, New York 10523
Model DDX-LP PrePaK™ System
2" (50mm), 2
3" (80mm), 4" (100mm),
6" (150mm) & 8" (200mm)
Low Pressure Dry-Pipe System
8 psi - 24 psi (0.6 bar - 1.7 bar)
System Air/Nitrogen Pressure
General Description
The Reliable Model DDX-LP PrePaK system (Sizes 2"
(50mm), 2½" (65 mm), 3" (80 mm), 4" (100 mm), 6" (150mm)
and 8" (200mm)) is a completely self-contained, supervised dry
pipe system that can be readily installed within a floor space
of less than 7 square feet (0.65 square meters). Refer to Fig.
1 for cabinet dimensions. Installation of the DDX-LP PrePaK
system requires just three piping connections: the water sup-
ply, the sprinkler system and the drain. Reference locations of
these piping connections are shown in Fig. 1. One electrical
supply connection is required. Note: The Model DDX-LP Pre-
PaK system is available with an optional 115V VAC (60Hz) air
compressor.
Full assembly drawings for the units are available on the Reli-
able Automatic Sprinkler Company website (www.reliablesprin-
kler.com).
The heart of the Reliable Model DDX-LP PrePaK system is
the Model DDX-LP Dry Pipe Valve. The Reliable Model DDX-LP
Dry Pipe Valve is a hydraulically operated, mechanical dry pipe
valve designed for use as a primary control valve in a low pres-
sure dry pipe valve system. The trim set used with the Model
DDX-LP Dry Pipe Valve contains the Reliable Model LP Dry Pilot
Actuator releasing device. This Actuator allows the system air
or nitrogen pressure to be considerably less than the water sup-
ply pressure (see Table A). The following benefits are a direct
result of lower air pressure:
1. In refrigerated area systems, lower air pressure decreas-
es the possibility of ice plugs that could impede or pre-
vent the flow of water to fire sprinkler heads in the event
of fire.
2. Lower air pressure allows for smaller capacity, lower cost
dehydration equipment, where required.
3. Lower air or nitrogen pressure can reduce water delivery
time when the system actuates, and in some cases, may
eliminate the need for an accelerator.
4. For systems supplied with nitrogen, low supervisory
pressure reduces the quantity of nitrogen required to
maintain the system pressure.
Bulletin 748 January 2022
/
" (65mm),
1
2