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Meter Trouble Shooting
PROBLEM: Leaking packing gland and/or housing
Two common causes of packing gland leakage are thermal expansion and hydraulic shock. If two valves in a piping system
(on either side of the meter) are closed at one time, and if the temperature rises as little as 1ºF in the system, it could result in a
rise in pressure within the system that would exceed the working pressure rating of the meter. To avoid this hazard caused by
thermal expansion, a pressure-relief valve of some kind must be installed in the system.
Hydraulic shock occurs when a large volume (mass) of liquid is moving through a pipe line at some flow rate and a valve is
suddenly closed. When the flow is so stopped, the entire mass of the liquid in the piping system acts as a battering ram, caus-
ing a shock effect within the meter. The greater the mass, length of line and/or velocity, the greater the hydraulic shock. Since
the valve is usually located at the meter outlet, the meter housing, packing gland and the meter internal members receive the
full impact of such hydraulic shock. To prevent this hazard a slow closing two-stage valve should be used with the meter. On
those systems where mass, length of line, etc. are of such magnitude as to preclude the elimination of hydraulic shock with the
use of a two-stage slow closing valve an impact-absorbing air cushioning device should be used.
O-Ring has been damaged or cover bolts have not been tightened enough.
PROBLEM: Product flows through meter but register does not operate.
A) Gear train motion interrupted by non-functioning gear due to broken pin or key. Replace pin or key where required.
B) If all meter parts are moving then problem is in register.
C) Remove register from meter. If all meter parts are moving but output shaft of adjuster assembly is not, adjuster is
worn and must be replaced.
D) If totalizer numerals (small numbers) on register are recording, but the big numerals are not moving, register needs
repair.
PROBLEM: Product flows through meter but register does not record correctly.
A) Adjuster assembly not properly calibrated, See METER CALIBRATION on page 13 for more instructions.
B) The factory installed gear train may have incorrect gearing ratio.
C) Check register for defects.
PROBLEM: No flow through meter.
A) Faulty non-functioning pump.
B) Foreign matter within the system, meter or components.
C) Meter has a broken rotor or rotor shaft.
D) Excessive wear on timing gears or bearings.
E)
Meter "frozen" due to build-up of chemical "salts" inside metering chamber, sufficient to stop rotation or rotors.
F)
Valve not open or not functioning.
PROBLEM: Meter runs too slow.
A) There is a flow restriction within the system. (i.e.: tees, elbows, valves, etc.)
B) Foreign matter in system, meter or components.
C) Product viscosity is different or has changed from what was originally known.
D) Meter gears or rotors partially "salted" enough to slow up rotation of parts.
E) Valve internal mechanism faulty. Valve does not open fully or the linkage is not properly adjusted.
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Table of Contents
Troubleshooting
