Radon fan replacement and repair in Duluth, MN

How to check your system

Most systems have a U-tube manometer on the pipe, a small clear tube with colored liquid. When the fan is pulling, the liquid sits higher on one side than the other. When the two sides are level, the system has no suction. Some homes have an electronic alarm in place of, or in addition to, the gauge.

Before assuming the fan is dead, check that its breaker or switch is on, and look for anything that has changed around the outside pipe, such as a crushed section or a blocked outlet. Do not open or cut into the pipe yourself.

Signs a fan is failing

Any of these is a good reason to have the system looked at:

• The liquid in the manometer is level or has moved noticeably from where it was marked at install.
• An alarm is sounding or showing a fault.
• The fan is silent, or you can feel that it is no longer vibrating or running.
• New grinding, rattling or humming sounds are coming from the fan.
• A recent radon test came back higher than earlier tests.
• Water is pooling around the fan housing or the fan is visibly corroded.

What replacement involves

Replacing a fan is usually a short job. Fans connect to the pipe with rubber couplings, so the old one can be removed and a matching unit installed without rebuilding the system. The contractor should confirm that the replacement has the right capacity, reseal the connections and check that the gauge shows proper suction when finished.

This is also a good time to review the rest of the system. A contractor can check whether the sump cover and seals are still tight, and whether the outlet still meets standards, since older systems were not always vented in the right spot. Minnesota requires a license for anyone doing radon mitigation in a building they do not own or lease.

Fan replacement is commonly quoted at a few hundred dollars for parts and labor. Prices vary with the fan and how hard it is to reach, so ask for a price before work begins.

When a repair is not enough

Sometimes the fan is fine and the system still is not doing its job. If a recent test is high but the gauge looks normal, the cause may be somewhere else. A new crack or an unsealed sump lid can let the fan pull basement air instead of soil gas. An addition, a finished basement or a new furnace can change how air moves through the house. A pipe that has come loose in the attic can release radon indoors.

A licensed professional can test the suction, look for leaks, and decide whether the system needs a stronger fan, another suction point or some resealing. If the original design never brought your level under 4.0 pCi/L, ask for the original test results and the paperwork, then have someone evaluate the design itself rather than swapping parts.

In winter, watch for ice around an exterior outlet in a long cold spell. Condensation in the pipe can freeze in very low temperatures, restricting airflow. If you see ice building at the top of the pipe or the gauge has moved during a cold snap, have it checked rather than trying to clear it from a ladder.

Look for the MDH tag on your system, too. It lists the installer's name, phone number, install date and license number, which is the fastest way to find who built it and whether a warranty may still apply. Keep your written operating instructions and warranty with your house records, since a future buyer will want them.

Retest after any repair

A new fan should do what the old one did, but the only way to be sure is to test. Run a short-term test after the system has been running for at least 24 hours. If you do not have a recent test on file, this one becomes your new baseline.

Common questions