Table 10-6.--Troubleshooting Chart
Trouble
Probable Cause
Checking Procedure
Remedy
Excessive frost or
Automatic opening of
Wait to see if condition is
Abnormal condition will
condensation on lines
relief valve.
temporary
disappear.
Tank not level. Piping end
Visual.
Level tank, or put piping
down.
end up.
Valves leaking.
Check for escaping gas.
Repair or replace.
Vacuum deterioration.
Check evaporation loss
Locate and repair leak,
rate.
and re-evacuate tank.
Burst disc fails to blow
This is a dangerous
Check lines for foreign
Reduce pressure by
above rated pressure
condition. Lines are
material. Check setting of
opening vent valve. Clear
obstructed by foreign
pressure relief valve.
or thaw lines. Replace
material or ice. Also, the
relief valve. Purge entire
applicable pressure relief
system.
valve has failed to operate.
Wrong burst disc
Compare with
Replace with correct disc
assembly.
replacement disc
assembly.
assembly.
Pressure relief valves do
Pressure gauge faulty or
Check calibration.
Perform calibration
not open above rated
incorrectly calibrated.
procedures. If gauge
pressure
cannot be calibrated,
replace.
Valve faulty or incorrectly
Build up tank pressure
Replace relief valve.
set.
and recheck valve.
Valve frozen.
Visual or manual.
Thaw valve.
Pressure relief valves
Pressure gauge faulty or
Check calibration.
Perform calibration
open at less than rated
incorrectly calibrated.
procedures. If gauge
pressure
cannot be calibrated,
replace.
Relief valve faulty or
Build up tank pressure
Replace relief valve.
incorrectly set.
and recheck valve.
Excessive relief valve
Ice in valve seat.
Bubble check relief valve
Warm valve to ambient
leaking below reseal
outlet.
temperature.
pressure (36 psig for P/N
22385, 54 psig for P/N
22387, and 71 psig for
P/N 22386 and 22386-1)
Foreign material or object
Bubble check relief valve
Replace relief valve.
lodged in valve.
outlet.
Faulty relief valve.
Replace relief valve.
10-16
