8
IOM-1078
Possible Cause
Remedy
A.
Shut-off valve at outlet is restricting flow.
A1.
Be sure shut-off valve at outlet is full bore or larger.
B.
Vacu-Gard set pressure too close to the set pressure
of the pressure relieving devices.
B1.
Check settings of valves and adjust if needed. The pressure
relieving devices must be set higher than the Vacu-Gard.
C.
Sense or flow line pipe is undersized.
C1.
Check all piping connected to Vacu-Gard for size and con-
figuration to prevent pressure drops and trapped condensate.
3. Vacu-Gard cycles rapidly.
Possible Cause
Remedy
A.
Worn o-rings or seat surfaces.
A1.
Replace worn parts. (See Maintenance Section for disas-
sembly and reassembly.)
B.
Foreign particles on o-rings or seat surfaces.
B1.
Clean and lubricate parts. (See Maintenance Section for
disassembly and reassembly.)
C.
Loose connections on Vacu-Gard.
C1.
Check all connections for tightness.
4. Vacu-Gard closes but will not shut-off tight.
SECTION VIII
VIII. TROUBLE SHOOTING GUIDE
Possible Cause
Remedy
A.
Incorrect sense line connection.
A1.
A2.
Check sense line and be sure it is connected from the sense
port on the Vacu-Gard to the tank.
Check sense line and shut-off valve for size and configura-
tion to prevent pressure drops and trapped condensate.
B.
Sense line is clogged.
B1.
Check sense line and sense port for blockage.
C.
Improper inlet and/or outlet connection.
C1.
Check and be sure supply line is connected to inlet of Vacu-
Gard and outlet of Vacu-Gard is connected to tank, making
sure it is not reversed.
D.
Loss of supply pressure.
D1.
Check supply pressure and see that it is within the range
stated on nameplate.
1. Vacu-Gard will not open.
Possible Cause
Remedy
A.
Sense line not installed.
A1.
Check that the sense line is properly connected.
B.
Vacu-Gard set pressure is higher than or too close
to the set pressure of the pressure relieving devices.
B1.
Check settings of valves and adjust if needed. The pressure
relieving devices must be set higher than the Vacu-Gard
setting. The greater the spread the better.
C.
Blanket gas is escaping from opening in tank.
C1.
Be sure all openings such as pressure relieving devices,
gauge hatches, etc., are closed and working properly.
D.
Malfunction of pressure relieving devices.
D1.
Check operation of pressure relieving devices.
E.
Blanket gas is escaping from faulty piping or con-
nections.
E1.
Check all piping and connections for tightness.
F.
Foreign particles trapped in Vacu-Gard.
F1.
Check Vacu-Gard for dirt and debris. (See Maintenance
Section for disassembly and reassembly.)
G.
Pilot inlet port is clogged.
G1.
Check pilot inlet port, filter and tubing.
H.
Vacu-Gard has loose connections.
H1.
Check and make sure all Vacu-Gard connections are tight.
2. Vacu-Gard will not close.
