airflow Issue

Paint Booth Airflow Alarm

Your airflow alarm is telling you something critical. Here's what it means and what to do.

Emergency: (877) 489-3727 Start Diagnosis

What You're Experiencing

The airflow monitoring system has triggered an alarm, indicating that air velocity or volume has dropped below safe operating thresholds.

Visual Signs:

Airflow warning light illuminated on control panel
Digital display showing low CFM readings
Manometer needle below green zone
PLC fault code displayed (varies by system)

Sound Signs:

Continuous or intermittent alarm buzzer
Change in fan motor sound (quieter than normal)
Unusual whooshing or whistling sounds

Safety Risks — Read Before Proceeding

critical(NFPA 33, OSHA 1910.94)

Explosive atmosphere buildup

Action: Stop all painting operations immediately. Do not use any ignition sources.

high(OSHA 1910.134)

Worker exposure to harmful vapors

Action: Evacuate booth area. Ensure workers have appropriate respiratory protection if re-entry is needed.

medium

Coating quality defects

Action: Do not continue painting—overspray contamination will cause defects.

Immediate Steps to Take

1
Stop all painting operations immediately
2
Do not reset the alarm without investigating the cause
3
Check the manometer reading—is it in the red zone?
4
Visually inspect exhaust filters for heavy loading
5
Listen for changes in fan motor sound
6
Check if dampers are in the correct position
7
Review the control panel for fault codes

Common Causes

Here are the most likely reasons you're experiencing this problem, ranked by how often we see them.

Clogged Filters

common

Exhaust or intake filters are loaded with overspray and particulates, restricting airflow. This is the most common cause and is easily preventable with...

Belt Slippage or Failure

common

The drive belt connecting motor to fan has stretched, slipped, or broken. Belts wear over time and require periodic replacement.

Damper Position Issue

occasional

Intake or exhaust dampers are stuck closed or not opening fully. Actuators may have failed or linkages could be disconnected.

Airflow Sensor Malfunction

occasional

The differential pressure sensor or airflow sensor has drifted out of calibration or failed. Sensors require periodic calibration.

Motor or Fan Failure

rare

The exhaust or supply fan motor has failed or is running at reduced capacity due to electrical or mechanical issues.

Ductwork Blockage

rare

Debris, collapsed duct sections, or ice buildup (in cold weather) is blocking the exhaust or supply air path.

Interactive Diagnostic Tool

Airflow Alarm Diagnostic

Step 1 of 5

Is the manometer showing low pressure differential?

If unsafe at any point: If you smell strong solvent odors outside the booth or see visible overspray escaping, evacuate the area and call WERCS emergency line immediately at (877) 489-3727.

When to Call WERCS

While some issues can be resolved with basic troubleshooting, these situations require professional service:

Alarm persists after filter replacement
Fan motor sounds abnormal or won't start
You smell solvents outside the booth
Dampers won't move or respond
Multiple fault codes on control panel
Booth hasn't passed inspection recently

Priority Service Available

(877) 489-3727

Expert technicians nationwide

Paint Booth Airflow Alarm FAQ

Common questions about this issue

No. Never reset an airflow alarm without identifying and fixing the root cause. Insufficient airflow creates explosive atmospheres and exposes workers to harmful vapors. Both are serious safety and compliance violations.

Filter change frequency depends on usage, but most facilities need to change exhaust filters every 1-2 weeks during active painting. Install a manometer if you don't have one—it tells you exactly when filters need changing.

Cold weather can cause ice buildup in exhaust stacks or ductwork, restricting airflow. It can also make belts stiffer and more prone to slipping. Ensure your makeup air unit is heating properly and check for ice in external ductwork.

Costs vary widely. Filter replacement is inexpensive ($50-200). Belt replacement is moderate ($200-500 including labor). Sensor replacement or motor repairs can be $500-2,000+. Emergency service costs more than scheduled maintenance.

Have a question not answered here?

Call us at (877) 489-3727

Can't Fix It? We Can.

WERCS expert technicians service paint booths and extraction systems nationwide. 24/7 emergency service available.

Call (877) 489-3727 Request Service Quote