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Spears® Ball Valve Trouble Shooting Guide

Spear True union valves are designed and produced for trouble-free operation and use. However, certain aspects of installation and application can result in valve malfunction.  This guide identifies some of the more common problems encountered and their necessary corrective actions. Such problems have been categorized as External Leaks, Internal Leaks, Frozen Movements, and structural Breakage.


External leaks


Possible Cause

Corrective Action

At Thread

or Socket Connections

Improper solvent cementing.



Improper threads.



Insufficient or improperly applied thread sealant: incompatible sealant (paste).


Over-tightened thread joint splitting connector.


Insufficient valve support splitting connector.

Replace end connector(s) according to installation instructions.


Check threads for proper size; replace or reinstall.


Reinstall thread connection according to proper procedures; check paste compatibility


Replace cracked end connector(s).



Replace cracked end connector(s). Add supports on each side of valve.

At Union Nuts

End connector misaligned.




Displaced or damaged o-ring; Particles in o-ring groove.



System contraction pulling end connectors; improper end connector spacing.


Loose Union Nut.


Displaced or pinched seal carrier o-ring.

Check system alignment – end connector(s) must be parallel. Check for adequate valve support.


Remove valve and inspect o-ring for physical of chemical damage. Check o-ring compatibility, replace accordingly. Clean and reseat o-ring.


Check thermal variations; anchor pipe each side of valve; install expansion loop. Correct spacing.


Re-tighten nut.


Remove and disassemble seal carrier; re-seat or replace o-ring.

At Stem

Damaged stem o-ring

Remove and disassemble valve stem; inspect for physical or chemical damage. Check o-ring compatibility, clean and replace accordingly.

 Internal leaking – In-line leakage past valve

Ball obstruction

Check that the valve is in its “full closed” position. If not, remove valve and check for solids blocking the ball port. Clean and reinstall valve.

Broken Stem

Remove end connectors and check for ball rotation while operating valve. Replace as necessary.

Seal Carrier Loose

True Union Valves – remove valve; CAREFULLY tighten seal carrier (located on the inlet end of the body).

IMPORTANT: Generally only a slight adjustment is required. A properly adjusted valve should have significant resistance to operation without binding – AVOID OVER_TIGHTENING!

Teflon Seat Damage or Debris Laden

Remove and disassemble valve seats o-rings; check for physical or chemical damage (nicks, cuts, scoring, etc.). Clean and replace as necessary.

Seat o-ring Displaced, Damaged, or Debris Laden

Remove and disassemble valve ball. Check for physical or chemical damage. Check o-ring chemical compatibility; clean and replace accordingly. Check for excessive system flow rate.

Ball Damage

Remove and disassemble valve ball. Check for physical damage (excessive nicks, scoring, etc.) at seat sealing surface (perpendicular to ball port). Clean surface; replace ball if necessary. Check for chemical damage and valve material (PVC, CPVC) compatibility.

Solvent-Cement (glue) Contamination from Installation Spillage

Remove valve and check for glue deposits on ball and seat areas. Clean, If possible; excessive damage may require component replacement.

Thermal Damage (component distortion)

Check system operating temperature, external heat sources (including direct sun), and heat generated from system design or valve placement.

Frozen movements – unable, or very difficult, to open/close; sometimes accompanied by stem break (shear)

Possible Cause

Corrective action

Internal Obstructions; Sediment or Particle Buildup; Solvent Cement on Ball

Remove valve and check for solids, debris, or solvent cement deposits blocking the ball or valve interior. Check for sediment particles lodged around ball-to-seat contact areas. Remove stem and check for the same. Clean and reinstall.

Over-tight Seal Carrier

True-Union Valves – remove valve; slightly loosen seal carrier (located on inlet end of body).

IMPORTANT: Generally only a slight adjustment is required (either valve). A properly

Chemical Attack (generally appears as distortion, peeling, etching or bleaching of ball sealing surfaces or other internal components)

Check Valve material (PVC, CPVC) chemical compatibility with system fluids. Be sure to consider operating temperatures with this determination.

 Structural Breakage


Possible Cause

Corrective Action

Handle Broken

Frozen movement.



External impact.

See “Frozen Movements” section. Replace.


Identify and correct source.

Handle stripped

Overextended open/close range.


Excessive exposure to direct-sunlight has softened handle material.

Replace handle.



Shield or screen valve from direct sun exposure.

Stem Sheared / Broken

Frozen movements; external impact.

See “Frozen Movements” section.

Broken Union Nut

Nut has been over tightened to draw-up align end-connectors; external impact.



Inadequate valve supports.



Excessive internal pressure / Hydraulic Shock 

Adjust spacing between end-connectors for proper valve lay-lengths. Check system alignment – end connector(s) must be parallel.


Provide system support on each side of valve.


Check System air pressure and surge pressures; check for entrapped air.

End Connector Break

System misalignment; External impact.


Over-tighten thread-joint connection.


Inadequate valve support.

Check System alignment – end connector(s) must be parallel.


Install new end connector according to installation instructions.


Provide system support on each side of valve

Body Break

External impact.


Excessive internal pressure.



System misalignment.



Inadequate Valve Support.



Chemical attack.

Identify and correct source.


Check system pressure and surge pressure; check for entrapped air.


Check system alignment – end connector(s) must be parallel.


Provide system support on each side of valve.


Check chemical compatibility of systems fluids.

Certain corrective actions of this guide may not be feasible with the compact ball valve (sealed unit).

Improper system operating temperatures and chemical incompatible can cause a variety of functional and structural failures. Be sure to use proper valve material-types for both temperature and chemical resistance.


Most valve problems are traceable to improper system design or installation. Be sure to have all design performed by qualified Engineer and installation made by properly trained personnel.


Spears valve Installation Instructions and maintenance procedures should be followed in conjunction with all corrective actions. 

Title: Spears® Ball Valve Trouble Shooting Guide
Description: This guide identifies some of the more common problems encountered and their necessary corrective actions
Published: 9/5/2008
Last Edited: 9/19/2013
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