Installation - Tyco DV-3 Manual

Page 6 of 10
PRESSURE OPERATED RELIEF VALVE
quires attention. The system will not
actuate or flood the sprinkler system
piping.

Installation

The deluge valve, swing check valve,
and all interconnecting piping must be
installed in a readily visible and acces-
sible location and in an area which can
be maintained at a minimum tempera-
ture of 40F/4C.
NOTE
Heat tracing is not permitted for the
deluge valve, swing check valve, or
any of the interconnecting piping. Heat
tracing will promote the formation of
hardened mineral deposits which can
prevent valve operation. Heat tracing
can also result in damage to the DV-3
Deluge Valve Diaphragm Assembly.
The 2-1/2 inch (DN65) Electric/Pneu-
matic Double Interlock Preaction Sys-
tems must be installed in accordance
with the following instructions. Proper
operation of the Double Interlock Pre-
action System depends upon it being
installed in accordance with the in-
structions given below. Failure to follow
these instructions may prevent the de-
vices from functioning properly as well
as void listings, approvals, and the
manufacturer's warranties.
FIGURE 4
Step 1. All pipe thread connections
must be free of scale and burrs before
installation. Use pipe thread sealant
sparingly on male pipe threads only.
Step 2. The DV-3 Deluge Valve must
be installed vertically as shown in Fig-
ures 2 and 3.
Step 3. The Double Interlock Preaction
Trim must be installed in accordance
with Figure 3.
The grooved end elbow fitting and cou-
plings are to be installed in accordance
with standard installation practices.
Care must be taken to make sure that
check valves, globe valves, etc. are
installed with the flow arrows in the
proper direction.
Drain tubing to the Drip Funnel must
be installed with smooth bends that will
not restrict flow.
Step 4. Attach the Model DV-3 Double
Interlock Label (25 - Fig. 3) to the 2
inch high x 4 inch (50 x 200 mm) wide
nameplate mounting pad on the Hand-
hole Cover of the CV-2 Swing Check
Valve. Place the Label over the manu-
facturer's logo nameplate, if one is lo-
cated on the pad.
Step 5. The Diaphragm Chamber Sup-
ply Connection (Fig. 3)must be con-
nected to the water supply side of the
System Main Control Valve to facilitate
setting of the DV-3 Deluge Valve.
PORV Operation
Area "A" of the PORV is connected
directly to the top of the DV-3 Dia-
phragm Chamber. In the set position,
water pressure is supplied through
the Screen (16) and the orifice in the
Diaphragm (14) to both sides of the
Diaphragm, Areas "A" and "B".
Therefore, because of the are differ-
ential and the force exerted by the
Spring (9), the Clapper (17) is held
closed.
When the DV-3 is tripped, water
pressure from the system side of the
DV-3 is directed towards the PORV
to Area "D". This pressure depresses
Diaphragm (3) which in turn de-
presses the Valve (6, 7). Opening of
the Valve releases pressure from
Area "B" into Area "C" where it is then
released to atmosphere.
With Area "B" reduced in pressure to
below that in Area "A", the Clapper
(17) lifts off the Seat (20) and allows
a constant vent of the DV-3 Dia-
phragm Chamber into Area "E"
where it is then released to atmos-
phere.
Step 6. Connect the Air Supply Con-
nection to an air or nitrogen supply.
Use of an automatic air or nitrogen
maintenance device is recommended
and may be required by the Authority
Having Jurisdiction. Refer to Graph B
for Double Interlock Preaction System
air pressure requirements.
An air dryer, when specified, is to be
installed as required by the Authority
Having Jurisdiction.
Step 7. The Low Air Pressure Alarm
Switch (Fig. 3) is to be adjusted to
operate on falling pressure at approxi-
mately 6 psi (0,4 bar) below the mini-
mum Double Interlock Dry System air
pressure requirement shown on Graph
B.
Step 8. The Pressure Relief Valve (21
- Fig. 3) is factory set to relieve at a
pressure of approximately 45 psi (3,1
bar), which can typically be used for a
maximum system pressure of 40 psi
(2,8 bar). The Pressure Relief Valve
may be reset; however, it must be be
reset to relieve at a pressure which is
in accordance with the requirements of
the Authority Having Jurisdiction.
To reset the Pressure Relief Valve, first
loosen the jam nut and then adjust the
cap accordingly — clockwise for a
higher pressure setting or counter-
clockwise for a lower pressure setting.
TFP1462