Existing systems
My Radon System Doesn't Seem to Be Working
An installed system can stop performing for reasons that range from trivial to structural. This page maps common symptoms to the category of issue they usually fall into, so you can describe the situation accurately when you ask for an evaluation.
Symptoms and what they may point to
| What you observed | Possible category | Recommended step |
|---|---|---|
| Radon test after mitigation is still elevated | Suction coverage, an untreated foundation zone, or a large unsealed opening | System performance evaluation with diagnostic measurements |
| Radon reading increased compared with an earlier test | A change in the system, the building or the sub-slab environment | Evaluation, plus a review of any recent renovation or drainage work |
| Fan appears to have stopped | Power supply, switch, or the fan unit itself | Professional inspection of the fan and its circuit |
| Manometer or gauge reading has changed or is level | Loss of suction, a blockage, a leak, or a stopped fan | Evaluation — a level gauge generally means the system is not under suction |
| Unusual noise, rattling or vibration | Fan condition, mounting, or something in the pipe | Inspection before the noise is 'fixed' by disconnecting anything |
| System is old and its history is unknown | Age is not proof of failure, but an unverified system is an unknown | Evaluation plus a current radon test |
| Visible pipe damage, disconnected joint or failed seal | Mechanical integrity of the piping or seals | Do not seal it yourself with tape — have it assessed |
| Sump cover, membrane or floor penetration has been opened | A short-circuit path that reduces suction under the slab | Evaluation of the opening in the context of the whole system |
Start with a current radon measurement
Whatever the symptom, the meaningful question is what the radon level in the home is now. A gauge tells you about suction in the pipe; a radon test tells you about the air people breathe. Both belong in an evaluation.
A system fails as a system
Replacing one component without assessing the others is how a problem returns. A fan that failed early may be a symptom of restricted airflow; suction lost at a joint may be the real reason readings changed.
What an evaluation typically covers
- Current radon measurement in the occupied space.
- Fan operation and electrical supply.
- Suction pressure and system monitor behaviour.
- Piping integrity, joints and seals along the full route.
- Exhaust termination and any obstruction.
- Sub-slab communication and whether coverage reaches all areas.
- Openings — sump covers, floor drains, chases, membrane condition.
- Changes to the building since installation.
Request an Existing-System Evaluation
Describe the symptom, your latest reading and what you know about the system. Independent radon professionals can assess the installed system as a whole.