You can tell that your radon fan is no longer operating when your system's alarm goes off or your manometer is level at zero, indicating a loss of proper airflow and suction.
Key Indicators Your Radon Fan May Be Failing
A properly functioning radon mitigation system relies on a fan to continuously draw radon gas from beneath your home and vent it safely outside. Recognizing the signs of a failing fan is crucial for maintaining effective radon reduction and protecting your indoor air quality.
1. Manometer Reading Zero
Your radon system typically includes a U-tube manometer, a small gauge that visually indicates the suction created by the fan. It's usually mounted on the white vent pipe.
- Normal Operation: The liquid in the manometer will show an uneven level, with one side significantly higher than the other, indicating active suction.
- Fan Failure: If the liquid levels in both sides of the manometer are completely level at zero, it means there is no pressure difference being created, and the fan is not pulling air. This is a primary indicator that your fan is not operating.
2. Radon System Alarm Activation
Many modern radon mitigation systems are equipped with an alarm or monitoring device designed to alert homeowners to a system malfunction.
- Alarm Signal: If your system's alarm sounds or displays a warning light, it's a direct signal that there's an issue, often related to the fan's operation or a loss of system pressure.
- Check the System: Investigate the alarm immediately to determine the cause, as it frequently points to a failed or failing fan.
3. Unusual Noises from the Fan
Radon fans are designed to operate quietly. Any change in their operational sound can be a sign of trouble.
- Common Sounds of Failure:
- Grinding or Scraping: Indicates worn-out bearings or internal components.
- Loud Humming or Buzzing: Could signify a motor struggling or an electrical issue.
- Excessive Vibrations: May suggest the fan is off-balance or its mounts are loose.
- Sudden Silence: If a fan that was previously audible suddenly becomes quiet, it might have stopped running entirely.
4. Lack of Airflow or Suction
You can sometimes perform a simple check to verify airflow.
- Tissue Test: Carefully hold a lightweight piece of tissue paper or a thin plastic bag near the exhaust pipe outlet (usually above the roofline or on the side of the house). If the fan is working, the paper should be pulled towards the pipe or flutter significantly. If it hangs still, there's no airflow.
- Audible Airflow: Listen for the subtle sound of air moving through the vent pipe near the fan. Absence of this sound indicates no air movement.
5. Fan Not Running (No Power/Sound)
Sometimes the simplest sign is the most obvious.
- Check Power: Ensure the fan's power switch is on and that the circuit breaker hasn't tripped.
- Listen and Feel: Place your hand on the fan housing (if safely accessible). A working fan will usually have a slight vibration and emit a low hum. If it's completely silent and still, it's not operating.
6. Increased Radon Levels
While not an immediate indicator, if you have re-tested your home for radon and found elevated levels after a period of lower readings, it could suggest your mitigation system, particularly the fan, is no longer functioning effectively.
- Retesting: Regular radon testing (every 2-5 years, or after significant home renovations) is recommended to ensure your system remains effective. If levels rise, inspect your fan and system thoroughly.
7. Age of the Fan
Radon fans, like any mechanical device, have a lifespan.
- Typical Lifespan: Most radon fans are designed to last 5 to 10 years, though some may last longer. If your fan is approaching or has exceeded this age range, it might be nearing the end of its operational life and prone to failure.
Summary of Radon Fan Failure Symptoms
| Symptom | Indication | What to Look For |
|---|---|---|
| Manometer Reading Zero | No suction from the fan. | Liquid levels in the U-tube are perfectly even. |
| System Alarm Activates | System malfunction detected. | Audible alarm or visual warning light on the system. |
| Unusual Noises | Worn components, motor issues. | Grinding, scraping, loud humming, buzzing, excessive vibration. |
| No Airflow/Suction | Fan not pulling air. | Tissue test fails at the vent pipe; no sound of air movement. |
| Fan Not Running | No power, internal failure. | No sound, no vibration when touched; check circuit breaker. |
| Increased Radon Levels | System ineffective. | Radon re-test results show elevated levels. |
| Old Fan Age | Approaching end of lifespan. | Fan is 5-10+ years old. |
What to Do If You Suspect a Bad Radon Fan
- Check the Power: Ensure the fan is plugged in, the power switch is on, and the circuit breaker hasn't tripped.
- Inspect Visually: Look for obvious damage to the fan or wiring.
- Contact a Professional: If the problem isn't a simple power issue, it's best to contact a qualified radon mitigation professional. Repairing or replacing a radon fan often involves working with electrical components and sealed systems, which is best left to experts.
