Cashco 1000 LP - Manual (Page 8)

IOM-1000LP-Basic 8
VII. TROUBLE SHOOTING GUIDE
SECTION VII
1. Erratic operation; chattering:
A. Oversized regulator; inadequate rangeability. A1. Check actual fl ow conditions, resize for minimum and maximum fl ow.
A2. Increase fl ow rate.
A3. Decrease pressure drop; decrease inlet pressure by placing a
throttling orifi ce in inlet piping union.
A4. Replace full orifi ce with reduced orifi ce; i.e. new cylinder required.
B. Worn piston/cylinder; inadequate guiding. B. Replace trim.
C. Flow induced instability. C1. Get straight runs of piping (5 diameters upstream, 10 downstream) to and
from regulator.
C2. Ensure outlet velocity is not excessive; use pipe reducer close to regulator
outlet.
C3. Add next higher range spring. Contact factory.
C4. If composition diaphragm, switch to metal diaphragm.
D. Improper (oversized) jet. D. Replace existing piston with new piston with proper jet.
E. Plugged trim. E. Remove trim and check for plugged holes in piston, or debris in guide zone
or jet zone.
2. Regulator outlet (downstream) pressure too low:
A. Setpoint too low. A. Turn adjusting screw down (CW) to increase setpoint.
B. Regulator undersized. B1. Confi rm by opening bypass valve together with regulator.
B2. Check actual fl ow conditions, resize; if regulator has inadequate
capacity, replace with larger unit.
C. Plugged inlet strainer. C. Remove strainer screen and clean; consider leaving screen out.
D. Plugged trim. D. Remove trim and check for plugged holes in piston, or debris in guide zone
or jet zone.
E. Incorrect range spring (turning adjusting screw E. Replace range spring with proper higher range. Contact factory.
CW does not allow bringing pressure level up to
proper level).
F. Too much droop. F1. Review droop expected. (See 2.B1 above.)
F2. Diaphragm setting too low; check setting and raise as required.
F3. Consider composition diaphragm over metal.
F4. Improper jet; make sure jet matches actual fl uid.
G. Restricted diaphragm movement (pressure G1. Diaphragm setting too high; check and lower as required.
plate hitting upstops). G2. Ensure no moisture in spring chamber at temperatures below freeze point.
Ensure no dust or debris entering vent opening. If rainwater or debris can
enter, re-orient spring chamber.
H. Restricted diaphragm movement (overstretched H1. Diaphragm setting too low; check and increase as required.
diaphragm). H2. Ensure no moisture in spring chamber at temperatures below freeze point.
Ensure no dust or debris entering vent opening. If rainwater or debris can
enter, re-orient spring chamber.
3. Leakage through the spring chamber vent hole.
A. Normal-life diaphragm failure. A. Replace diaphragm.
B. Abnormal short-life diaphragm failure. B1. Can be caused by excessive chattering. See No. 1 to remedy chatter.
B2. Can be caused by corrosive action. Consider alternate diaphragm material.
B3. For composition diaphragms, ensure not subjecting to over-temperature
conditions.
B4. Downstream (outlet) pressure buildup occuring that overstresses
diaphragms.
C. Pusher plate gasket leaking. C. Replace gasket.
Possible Causes Remedies
Possible Causes Remedies
Possible Causes Remedies