Groth 1401E User Manual
Page 9

8
TROUBLESHOOTING GUIDE
PROBLEM
INSPECTION
SUGGESTED CORRECTIVE ACTION
Vapor flowing at tank 
pressure below specified 
set point. 
 
Visual, audible or 
vapor detector 
Check actual set pressure on tank if field test connection is 
installed. Otherwise remove unit and test for: Incorrect 
pressure and blowdown setting using setting and testing 
procedure in this manual. Damaged seals, seat or 
diaphragms. Damaged spring or other components. 
Foreign material or corrosion in pilot. 
Vapor not flowing at 
tank pressure above 
specified set point. 
 
Visual, audible or 
vapor detector 
Check actual set pressure on tank if field test connection is 
installed. Otherwise remove unit and test for: Incorrect 
pressure and blowdown setting using setting and testing 
procedure in this manual. Plugged sense line or internal 
orifices. Foreign material or corrosion in pilot. 
Vapor leaking from 
spring bonnet vent 
Visual, audible or 
vapor detector 
Ruptured diaphragms; remove and replace.
Vapor leaking from body 
vent 
Visual, audible or 
vapor detector 
Damaged seal, seat or body diaphragm, or stem O-Ring. 
Remove and replace. 
Incorrect blowdown 
pressure 
Visual, audible or 
vapor detector 
Remove and set according to setting and testing procedure 
in this manual. 
 
RECOMMENDED SPARE PARTS 
 
When ordering spare parts, include model and serial 
number of the valve, pressure setting, blowdown 
setting and required material for soft goods. 
 
TABLE 3
RECOMMENDED SPARE PARTS
Item Description
Qty
15 Diaphragm,
actuator
2
40 Diaphragm,
body
1
19 O-Ring,
blowdown
1
28 O-Ring,
stem
1
27 O-Ring,
seat
1
32 O-Ring,
disc
1
35
Gasket, spring bonnet
1
41 Gasket,
body
1
10 Gasket,
actuator
2
25 Washer,
spacer
3
22 Stem
1
26 Screw,
stem
1
34 Bushing,
seat
1
33 Disc
1
20 Needle,
blowdown
1
30 Spacer,
central
1
17 Screen,
filter
1
MAINTENANCE 
 
The 1401E pilot does not require routine lubrication 
or adjustments. It should be checked periodically, at 
least once a year, to confirm the valve is functioning 
properly and that the set point is correct. The pilot 
valve is a fail safe device because failure of any seals 
or diaphragms will cause pressure to be vented to 
atmosphere, thereby allowing the pressure relief 
valve to open under pressure. 
 
Groth Corporation strongly recommends that all 
service performed on a pilot operated valve be done 
at the factory or a factory authorized repair center. 
Trained mechanics with specialized test equipment 
will ensure that the valve is accurately set. Flow 
capacity can be measure at the specified over-
pressure condition, if specified on the purchase order. 
 
CAUTION
If the valve must be disassembled for any reason, 
first make sure all pressure to the valve is blocked 
and pressure trapped in the valve vented safely. 
Refer to your company procedures when handling 
toxic or other hazardous materials. 
