Instruction manual

6.
Once the clapper has opened, the lever acts as a latch,
preventing the clapper from returning to the closed posi-
tion. Water from the supply flows through the Deluge Valve
into the system piping. Water also flows through the Deluge
Valve alarm outlet to the alarm devices.
After system shutdown, resetting the Model DDX Deluge
Valve is quite simple. Doing so only requires pushing in and
turning the reset knob at the rear of the valve (see Fig.1).
The external reset feature of the Model DDX Deluge Valve
provides a means for simple, economical system testing,
which is one essential facet of a good maintenance pro-
gram. The external reset feature does not, however, elimi-
nate another important facet of good maintenance, namely,
periodic cleaning and inspection of the internal valve parts.
In the event that water builds up inside the valve due to
condensate from the air supply system or water left inside
from valve system testing, a drain is available for venting.
After closing the main supply valve, a small valve over the
drain cup can be opened slightly until the water inside the
valve body and the main pipe column has drained. See
the section titled “Draining Excess/Condensate Water From
System” in this bulletin for the detailed procedure.
The Model B Manual Emergency Station (see Fig. 3) is also
included in the Reliable Single Interlock Preaction System
trim set. It consists of an aluminum nameplate mechanically
attached to a ball valve. The valve handle in its OFF posi-
tion is guarded against accidental turning to the ON position
(and system discharge) by a nylon cable tie provided with
each trim kit. The cable tie is inserted, as shown in Fig. 3,
after the system has been restored for operation. The ny-
lon cable tie is designed to allow, in case of an emergency,
forceful turning of the valve handle to the ON position. As
an alternative to the Model B Hydraulic Manual Emergency
Station, the Model A Hydraulic Manual Emergency Pull Box
(see Reliable Bulletin 506) is also available and can be pro-
vided as an option.
Whenever ambient temperature conditions are high, the
water temperature in the Model DDX Deluge Valve’s push-
rod chamber could possibly increase, thereby increasing
the pressure in the chamber to values exceeding the rated
pressure of the system. In an indoor installation where stan-
dard room temperatures are exceeded, a pressure relief kit
may be needed. Pressure relief kit, P/N 6503050001, can be
installed into the pushrod chamber’s releasing line to limit
the pressure to 175 psi (12,1 bar).
Pressurizing Line Connection
The water supply for the push-rod chamber must be pro-
vided by connection of its inlet pressurizing line to the wa-
ter supply piping. Pressurizing lines for multiple Model DDX
Deluge Valve push-rod chambers must never be manifold-
ed together, having only a single tap on the water supply
piping. Each Model DDX Deluge Valve must have its own
push-rod chamber pressurizing line connection. This con-
nection must be made on the supply side of the main water
supply control valve. This can be accomplished by:
Using a tapped connection directly below or next
to the main water supply control valve using a
welded outlet or the appropriate mechanical fit-
tings. A grooved-end outlet coupling is one way
to achieve this (see Fig. 2); or
Using a water supply control valve that has an
available threaded (NPT) supply-side tap design
to allow for a direct water supply connection to
the Model DDX Deluge Valve’s push-rod cham-
ber.
Caution: Reliable’s DDX valve is designed with an inlet
restriction built into the pushrod chamber. It is important
not to introduce additional restrictions into the direct wa-
ter supply connection or the discharge from the pushrod
chamber by installing additional valves or improperly in-
stalling the copper lines used in the trim of the valve.
Hydrostatic Testing of DDX Valves and DDX
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 and maintain
that pressure without loss for two hours. Fire sprinkler sys-
tems with working pressures above 150 psi are required to
be hydrostatically tested at 50 psi above the system work-
ing pressure and maintain that pressure without loss for two
hours. In addition to the hydrostatic tests described above,
dry pipe and double interlock preaction 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
that exceed the working pressure of the valve and trim kit for
the two-hour test period. The valve and applicable trim kit
have been tested, approved and listed under these condi-
tions and as such, hydrostatic testing in accordance with
NFPA 13 is acceptable. In addition, the clapper can remain
in the closed position and the trim kit need not be isolated,
as each has been designed to withstand hydrostatic testing
as required by NFPA 13.
Hydrostatically testing the valve and trim to pressures
higher than their rating is limited to the hydrostatic test as ref-
erenced by NFPA 13. It does not address the occurrence(s)
of a “water hammer” effect, which can indeed damage the
valve. A “water hammer” in the water supply piping of the
valve can create pressures in excess of the rated pressure
and should be avoided by all necessary means. This con-
dition may be created from improper fire pump settings,
underground construction work, or an improper venting of
trapped air in the water supply piping.
System Design Considerations
The automatic sprinklers, air compressor, releasing devic-
es, electric releasing control equipment, fire detection de-
vices, manual pull stations, and signaling devices which are
utilized with the Single Interlock Preaction System must be
UL or ULC Listed or FM Approved, as applicable.
The Deluge Valve, and all interconnecting piping must be
located in a readily visible and accessible location and in an
area that can be maintained at a minimum temperature of
a.
b.