Applicable Systems
Wilo Circulator Pump
Symptoms
The Wilo pump displays alarm W003, indicating mechanical seal leakage. The seal is leaking beyond the allowable rate, risking bearing contamination and environmental issues.
Possible Causes
- Seal faces worn or cracked from abrasion or thermal stress
- Seal spring or bellows fatigued from thermal cycling
- Shaft sleeve grooved or damaged, preventing proper seal seating
Troubleshooting Steps
- Step 1: Measure the leakage rate and compare to manufacturer limits
Leakage is within allowable drops per minute for the seal type and size - Step 2: Inspect the seal faces for cracks, scoring, or wear tracks
Faces are flat, smooth, and show no radial scoring or thermal cracking - Step 3: Check the shaft sleeve surface condition
Sleeve surface is smooth and within the allowable wear tolerance
How to Reset
To reset: 1) Replace the mechanical seal with a new one. 2) Replace the shaft sleeve if grooved. 3) Ensure proper installation alignment and restart.
Source: Wilo Pump Installation and Operating Manual, Wilo SE
Category: Pump