2.
When using the Reliable DDX-LP PrePak the sprinkler sys-
tem is pressurized with air provided by the optional factory-
installed air compressor or on-site Nitrogen supply and is
monitored by a system pressure switch. If bottled Nitrogen is
being used as the supervisory gas, an optional Nitrogen Kit
is available. This kit contains a regulator and an additional
pressure switch that is used to monitor any low pressure
conditions that may arise due to having a limited Nitrogen
supply. When using Nitrogen, the primary supervisory gas
should be the Nitrogen (not standard air) due to moisture
concerns (i.e. freezing conditions). The optional factory-
installed air compressor should be utilized merely for initial
fill and make-up air when the Nitrogen supply is not active.
Note:
Compressed air is not to be considered dry air and
may create ice plugs in the sprinkler system piping.
When a fire sprinkler operates, there will be a loss of air or
Nitrogen pressure in the sprinkler system piping which will
cause the Model LP-Dry Pilot Actuator to open. The opening
of this device allows the Model DDX-LP PrePak valve to flow
water into the system piping.
A Model B Hydraulic Manual Emergency Releasing sta-
tion is standard equipment in the Reliable DDX-LP PrePak. It
consists of an aluminum nameplate mechanically attached
to a ball valve. The valve handle in its OFF position is guard-
ed against accidental turning to the ON position (and sys-
tem discharge) by a nylon cable tie provided with the DDX-
LP PrePak assembly. The cable tie is designed to allow, in
case of an emergency, forceful turning of the valve handle
to the ON position.
Listings and Approvals
1. Underwriters Laboratories, Inc. Listed and Certi-
fied for Canada (cULus) as an assembled unit in the
“Special System Water Control Valves Assembled
Units” category, (VKYL).
2. Factory Mutual Approved as a Dry Pipe Sprinkler
System.
Technical Data
1. The Reliable Model DDX-LP PrePak is rated for a mini-
mum water supply pressure of 20 psi (1.4 bar) and a
maximum water supply pressure of 250 psi (17.2 bar).
Note: 1 bar = 100 kPa.
2. Friction loss, expressed in equivalent length of Sched-
ule 40 pipe and based on Hazen-Williams Formula is:
System Size
Equivalent Length
2” (50 mm)
19.4 ft (1.3 m)
2½” (65 mm)
24.5 ft (1.8 m)
3” (80 mm)
28.9 ft (3.8 m)
4” (100 mm)
32.8 ft (17.7 m)
6” (150 mm)
54.7 ft (21.8 m)
8” (200 mm)
79.3 ft (24.2 m)
The equivalent length in the table above includes the
Model DDX-LP PrePak valve, supply manifold tee, sup-
ply side control valve, and the section of pipe above the
Model DDX-LP PrePak valve.
3. Shipping Weight:
System Size
Weight
2” (50 mm), 2½” (65 mm)
& 3” (80 mm)
554 lb. (252 kg)
4” (100 mm)
710 lbs (322 kg)
6” (150 mm)
800 lbs (363 kg)
8" (200mm)
1350 lbs (531kg)
4. Refer to Figure 1 for dimensions.
The following is a list of Technical Data Bulletins which de-
scribe the valves and devices which are used in the system:
Device
Reliable Bulletin #
(unless otherwise noted)
Model DDX-LP PrePak Deluge
Valve
Reliable Bulletin 519
Model DDX-LP Dry Pipe Valve
Reliable Bulletin 338
Low Air Pressure Switch
Potter, 5401564
Alarm Pressure switch
Potter, 5400928
Nitrogen Pressure Switch
Potter, 5400930
Mechanical Sprinkler Alarm
Reliable Bulletins 612/613
Desiccant Dryer
Wilkerson Catalog 9EM-TK-190-4
Installation Requirements
The automatic sprinklers utilized with the DDX-LP PrePak
must be UL and/or ULC Listed or FM Approved, as appli-
cable.
The steel enclosure and all the interconnecting piping
must be located indoors in a readily visible and accessible
location and in an area that can be maintained at a mini-
mum temperature of 40°F (4°C).
Note:
Heat tracing is not
permitted. The Model DDX-LP PrePak PrePak operation is
controlled by the Model LP Dry Pilot Actuator. The introduc-
tion of moisture into the system piping exposed to freezing
temperatures can create ice blockage, which could prevent
proper system operation. As a minimum, the air supply
should be taken from the area of lowest temperature within
the protected area. The air supply system must be carefully
designed to prevent plugging by frost deposits. Special re-
quirements, such as those in FME&R “Installation Guidelines
for Refrigerated Storage” may need to be incorporated.
Hydrostatic Testing of DDX-LP PrePak Valves and
DDX-LP PrePak Systems
As required by NFPA 13, fire sprinkler systems with work-
ing pressures up to and including 150 psi are to be hydro-
statically tested at a water pressure of 200 psi. Fire sprinkler
systems with working pressures above 150 psi are required
to be hydrostatically tested at 50 psi above the system work-
ing pressure. In addition to the hydrostatic tests described
above, dry pipe systems require an additional low pressure
air test.
In some cases, hydrostatic testing (in accordance with the
NFPA 13 requirements noted above) will result in pressures
