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Replacing a radon fan: matching model, pipe size and couplings

Short answer: The safest choice is the same model that is installed now, or one a radon professional recommends, because radon fans range widely in airflow and suction and the right one depends on the soil under your home. Note the model on the fan label and your pipe size (3-inch or 4-inch). An installation kit bundles a fan with couplings, a power cord kit and a manometer.

Safety: Shut off power before removing the old fan. Electrical connections must meet local code; use a qualified electrician if you are unsure.

Step by step

  1. Read the label. Write down the model on the existing fan and check the manometer reading from before it failed.
  2. Measure the pipe. Most residential systems use 3-inch or 4-inch PVC. Couplings are sold by fan-side and pipe-side size.
  3. Choose like for like. A fan with very different performance can under-draw (radon stays high) or over-draw (more noise and energy use).
  4. Install and record. Mount the fan outdoors or in an attic, never in living space, and mark the new manometer reading.
  5. Retest. Run a radon test with the new fan running at least 24 hours, and within 30 days of installation.

Fans and installation kits

Common questions

Can I put a stronger fan on my system?

Only if the system needs it. A professional can measure suction and airflow to decide. Stronger fans use more electricity and can be louder.

What comes in a radon fan installation kit?

The kits we list include the fan, two flexible couplings sized to the pipe, a 6-foot power cord kit and a U-tube manometer. See each listing for the exact contents.

Do I need a new manometer?

Not if the existing one is intact and readable. Re-mark the reading with the new fan running.

Shop radon mitigation parts Flexible couplings and noise

Related categories: Radon Mitigation Supplies. General information only; follow the equipment maker's instructions and local codes. Updated 2026-11-14.