Radon System Maintenance: What Homeowners Need to Know

You've got a radon mitigation system installed. Great. Now what? The good news is these systems are low-maintenance. But "low" doesn't mean "zero." Here's what you actually need to do to keep it working.

Check Your System Monthly (Takes 10 Seconds)

Every radon system has a u-tube manometer — that little U-shaped tube with colored liquid mounted on the PVC pipe, usually in the basement. It tells you whether the fan is creating suction.

How to read it:

• Liquid levels are uneven (one side higher than the other): System is working. The fan is pulling air and creating suction under your slab. You're good.
• Liquid levels are even (same height on both sides): The fan isn't creating suction. Either the fan died, lost power, or there's a blockage. Time to investigate.

That's it. Glance at it once a month when you're in the basement. If the levels are uneven, move on with your life.

Listen to the Fan

A healthy radon fan makes a low, steady hum. You get used to it fast — most homeowners forget it's there within a week. But pay attention if:

• It's suddenly louder: Bearings might be going. Not an emergency, but schedule a replacement before it fails completely.
• It's making grinding or rattling noises: Bearings are definitely failing. Replace soon.
• It's silent: Fan stopped. Check the breaker first. If the breaker's fine, the fan motor burned out and needs replacement.
• It's vibrating the pipe: The fan might have shifted or a mounting bracket loosened. Usually a quick fix.

When to Replace the Fan

Radon fans typically last 5-12 years depending on the brand, how hard they're working, and your climate. Some high-quality fans (like RadonAway GP501) can last 15+ years. Others might only make it 5.

Signs it's time:

• Fan is making loud or unusual noises
• Manometer shows reduced suction (liquid levels are closer to even than they used to be)
• Your re-test shows radon levels creeping up
• Fan is more than 10 years old (preventive replacement isn't a bad idea)

Cost for fan replacement: $200-$500 including labor. Some handy homeowners do it themselves — it's basically disconnecting the old fan from the pipe, mounting the new one, and reconnecting. But if you're not comfortable on a ladder near your roof, call a pro.

Re-Testing Schedule

The EPA recommends re-testing every 2 years, even with a working system. Here's a practical schedule:

• 48 hours after installation: Your contractor should do this (or you should). Confirms the system works.
• 6 months later: Catches seasonal variation. If your install was in summer, test in winter (or vice versa).
• Every 2 years after that: Use a $15-20 long-term test kit for best accuracy. Leave it out for 90+ days.
• After any fan replacement: Confirm the new fan is pulling enough suction.
• After major renovations: Especially if you changed anything in the foundation area.

Signs Your System Needs Attention

Beyond the monthly manometer check:

• Ice forming on the exhaust pipe in winter: Normal in cold climates, but excessive ice can block the pipe. Some systems have a pipe heater or heat tape for this. If you see the pipe completely blocked with ice, call your contractor.
• Water in the pipe: Condensation is normal. But if you hear water gurgling in the pipe, there might be a low spot where water is collecting and blocking airflow. A contractor can fix the pitch.
• Cracks in the PVC pipe: UV exposure can degrade exposed pipe over time. If you see cracks or discoloration on the roof section, it should be replaced.
• Sump pit cover not sealed: If your system draws from a sump pit, the cover needs to stay sealed. If it's been removed or cracked, radon can bypass the system.

What NOT to Do

• Don't unplug or turn off the fan (even temporarily). Radon builds back up within hours.
• Don't seal the manometer. It needs to be open to read accurately.
• Don't modify the pipe routing without consulting a professional. The system was designed with specific airflow in mind.
• Don't cover the exhaust point on the roof, even in winter.

Need a Repair or Replacement?

If your system needs work, find a certified contractor who does repairs — not just new installs. Fan replacement, pipe re-routing, and system upgrades are common services.

Sources: EPA "Consumer's Guide to Radon Reduction," RadonAway fan manufacturer guidelines.

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