Technical data

TECHNICAL DATA
The Viking Corporation, 210 N Industrial Park Drive, Hastings MI 49058
Telephone: [phone] Technical Services 877-384-5464 Fax: [phone] Email: [e-mail]
PREACTION SPRINKLER
SYSTEM
Page 62
February, 2010
B. During Normal Power Supply Conditions, Faults or Complete Loss of Power
During normal power conditions if the system piping and/or the sprinklers are damaged, the low pres-
sure supervisory switch will activate a supervisory alarm at the VFR400 Release Control Panel and
the normally open solenoid valve will be powered closed to prevent the deluge valve from opening.
In the event of a fire during a fault on the input circuit wiring, loss of primary AC power or complete
loss of all power, the deluge valve will open allowing water flow if the following conditions occur:
1. The initiating devices activate causing the VFR400 Release Control Panel to enter an alarm and
release condition. The normally closed solenoid will open allowing water pressure to be relieved
from the priming chamber of the deluge valve. With pressure relieved from the prim-ing chamber,
the deluge valve will open and allow water flow. Water will not be discharge into the protected
area until a sprinkler head operates.
2. During a fault condition on the input wiring which caused a trouble alarm on the VFR400 release
control panel or a complete loss of normal AC power and standby battery backup power the nor-
mally open solenoid is prevented from operating. During this condition activation of a sprinkler
head will allow a pneumatic release of the deluge valve. Water pressure will be relieved from the
priming chamber, the deluge valve will open and allow water to flow.
C. Loss of Power During Operation
If all power fails while the system is flowing water, the normally open release solenoid will open and
the normally closed release solenoid will remain closed. The PORV is already pressurized open to
prevent pressure in the chamber from building up. Water from main supply will continue entering the
system, and through any open sprinkler(s).
D. Troubleshooting System Components
1. PORV
The Viking Model C-1 PORV is a field serviceable part that is made up of various components.
This device is essentially a hydraulic latch which holds the valve open, even when using reset-
table detection devices.
Problem:
The PORV won’t reset after the valve water supply is shut off and the system is drained.
Remedy:
1. There is water pressure still being applied to the sensing end of the PORV. Break the
union in the sensing line to see where the water is coming from, and correct the problem.
There should be no water pressure in the sensing line once the system is shut down and
drained.
2. There are metal shavings, mud or silt caught under the clapper of the PORV. Remove
the drain line from the discharge end of the PORV, then slightly open the priming line
valve. With the eraser end of a pencil, push on the clapper and let some water flow out
the discharge end of the PORV. This may wash the metal shavings, mud, etc, away from
the underside of the clapper. If it does not clear the obstructions, then the PORV must be
removed, disassembled, cleaned, reassembled and installed.
3. There is mud or silt, etc, inside the PORV at the sensing end, keeping pressure on the
diaphragm and schrader core valve. This is very common where river water or non-potable
water is being used. The PORV must be disassembled, cleaned, then reassembled.
4. The valve stem of the schrader core valve is bent, or the diaphragm at the sensing end
is distorted. With the priming valve closed and the system still shut down, remove the six
screws at the sensing end of the PORV, inspect the diaphragm for distortion, and check
the schrader core valve to inspect the stem. If the diaphragm is distorted or the schrader
core valve stem is bent, replace with new.