Fault symptom

Cause

Solution

Joint leakage between valve body and valve cap

Uneven tightness of screw

Adjust screw to make it even.

Invalid gasket

Replace gasket.

Leakage of sealing surface contact

Dirt exists on sealing surface or sealing joints

Clean it.

Damaged sealing surface

Replace or repair sealing gasket.

Ineffective valve clack

Dirt exists on the contact of internal and external circles.

Clean it.

Rust spot exists on the external circle of valve clack

Clean away rust spot and apply rust-proof oil

Leakage of sealing surface

Sealing surface is damaged or has dirt.

Repair sealing surface, or remove dirt

Damaged sealing gasket

Replace sealing gasket

Slow open and close speed

Operating place is damaged during assembly. The surface is coarse, has blur, or O-ring is damaged.

Repair, replace O-ring or re-assemble

Insufficient spring force

Replace spring

Leakage of joints of locknut

Locknut is not tightened.

Tighten the locknut

Damaged gasket

Replace gasket