IOM-DA0
9
SECTION IX
IX. TROUBLE SHOOTING GUIDE
When trouble shooting this regulator there are many possibilities as to what may be causing problems. Many times, the regulator
itself is not defective, but one or more of the accessories may be. Sometimes the pro cess may be causing difficulties.
The key to efficient trouble shooting is information and communication. The customer should try to be as precise as possible
in their explanation of the problem, as well as their understanding of the application and operating con di tions.
It is imperative the following information be provided by the customer:
• Fluid (with fluid properties)
• Range of outlet pressure
• Range of flow rate
• Range of fluid temperature
• Range of inlet pressure
• Range of ambient temperature
Pressure readings should be taken at every location where pressure plays a role - i.e., regulator inlet (as close as possible to
inlet port), regulator outlet (as close as possible to outlet port), etc.
Following are some of the more common complaints along with possible causes and remedies.
1. Erratic regulation, instability or hunting.
Possible Causes
Remedies
A.
Sticking of internal parts.
A.
Remove internals, clean, and if necessary, replace.
B. Oversized
regulator.
B.
Check actual flow conditions; resize regulator for min i mum and maxi-
mum flow; if necessary, replace with smaller size regulator.
2. Downstream pressure will not reach desired setting.
Possible Causes
Remedies
A.
Supply pressure is down (confirm on pressure
gauge.
A.
Increase supply pressure.
B.
Undersized regulator.
B.
Check actual flow conditions; resize regulator for min i mum and maxi-
mum flow; if necessary, replace with larger regulator.
C.
Pressure loading system pressure restricted.
C1. Clean restriction or bleed orifices.
C2. Clean
filter(s).
C3. Clean loading pressure control device.
D.
Faulty loading pressure control device.
D.
Replace/repair loading pressure control device.
6. Leakage at body/cover flange.
Possible Causes
Remedies
A.
Body bolts not torqued properly.
A.
Torque to proper value (see Section VII, F-11).
B.
Pressures may be too high.
B.
Consult factory.
7. Leakage across seat.
Possible Causes
Remedies
A.
Contamination (debris) in regulator.
A. Remove internals, clean, & replace sealing and seating elements. *
B.
Oversized regulator; valve plug operates
directly next to seat.
B.
Check actual flow conditions; resize regulator for minimum and maxi-
mum flow; if necessary, replace with smaller size regulator.
* Seat leakage may be diagnosed when a failure of the dynamic side seal has occurred. Inspect both potential internal leak paths.
