Manual
The manual contains the inspection, maintenance schedule, and instructions
for repairing and replacing parts for all NV4000 Pressure/Vacuum Vents. The
following schedule, based on the environmental conditions in the northern
United States, is only a recommendation: Inspection and maintenance intervals
must be adjusted according to use and operating conditions. If any parts are
damaged, refer to the Product Maintenance section.
Installation Procedure
1. Remove existing vent
2. Apply anti-seize compound to the threads of the new vent
3. Install new vent and hand tighten
4. Using a 15/16” wrench, socket, or pliers tighten the vent 1/8 to 1/4” turn
(approximately 12-15 ft-lbs.) Test
Do not over tighten as the may cause damage to the vent
Product Maintenance
This Pressure Vacuum Vent contains a flame arrestor screen (Item 7) which
over time may collect dirt, leaves and other foreign objects. IT IS THE USER’S
RESPONSIBILITY TO INSPECT AND KEEP THIS AREA CLEAN SO THAT THE VENT
CAN OPERATE PROPERLY.
Disassembly: Remove the snap ring (9) then press and rotate the rollover
housing (5) counterclockwise. Gaskets should be inspected for cuts, swelling,
or deterioration. If any of these conditions are found, seals should be replaced.
Inspect seal surfaces for scratches or other damage that may lead to improper
sealing. If these conditions exist, replace the vent.
Cleaning: If the vent is operating in a dirty environment or more aggressive
liquids, more frequent maintenance will be required. We also recommend
periodic testing of the vent to ensure that it is working properly. If it is not
functioning properly clean filter/flame arrestor (7), vacuum poppet assembly (8),
pressure poppet (4), body sealing surfaces (1), and shutoff puck assembly (10),
with warm soapy water.
Re-assembly: Install components in reverse order of removal. For easy re-
assembly, ensure shutoff puck is centered in the vent when installing the
rollover housing. Once re-assembled, a light tap to the vent may be needed to
help align components to their natural state.
CAUTION: The filter/flame arrestor must be cleaned periodically for safe
operation.
ITEM
PART NUMBER
DESCRIPTION
QTY.
1
13154
Body
1
2
13155
Spring, Pressure
1
3
13156
Spring, Vacuum
1
4
13157
Poppet, Pressure
1
5
13159
Housing, Rollover Puck
1
6
13163
Gasket, Flat
1
7
13167
Flame Arrestor
1
8
13192
Assembly, Vacuum Poppet
1
9
13207
Ring, Wire External Snap
1
10
13208
Assembly, Shutoff Puck
1
13212
Instruction Sheet
