Warranties, Retesting, and Post-Install Expectations

A radon mitigation install isn't really finished when the contractor leaves. It's finished when the post-mitigation test comes back below 4.0 pCi/L, when you've got the system documentation in your file, and when the warranty terms are written down and clear. This page covers what to expect on all three.

A complete Colorado mitigation install typically has three separate warranties — they overlap in time but cover different things.

Workmanship warranty (from the contractor)

Covers the install itself — the piping, sealing, fan mounting, manometer installation, electrical work.

• Industry standard: 1–2 years on labor.
• Premium installs: Some Colorado contractors offer 5 years.
• What's covered: Pipe leaks, fan housing issues, sealing failures, manometer mounting problems, electrical issues caused by the install.
• What's not: Normal fan wear after warranty period, damage from causes unrelated to the install, owner modifications.

Fan manufacturer warranty

Covers the fan itself — typically 5 years from RadonAway, Fantech, or Festa AMG.^[1]

• What's covered: Motor failure, bearing failure, manufacturing defects.
• What's not: Storm damage, ice damage, electrical surges, owner damage.
• How to claim: Usually through the original installer. Keep the fan model and serial number in your files.

Performance warranty (optional but ideal)

A guarantee that the system will reduce indoor radon below 4.0 pCi/L on the post-mitigation test.

• Industry standard: Most reputable Colorado contractors offer this in writing.
• What's covered: If the post-mit test doesn't bring levels below 4.0 pCi/L, the contractor adds an additional suction point, upgrades the fan, or takes other corrective action at no extra cost.
• Limit: Usually 1 year post-install. Get this in writing on the quote.

Per EPA recommendation:^[2]

• Within 30 days of system activation.
• No sooner than 24 hours after the fan starts running.
• 2 to 7 days of test duration.
• Closed-house conditions for 12 hours before and during.
• Lowest livable level, 2–6 feet above the floor, away from drafts and humidity.

EPA also recommends having the post-mit test done by an independent (non-installer) tester to avoid any conflict of interest. Some Colorado contractors include this in the quote; others charge $125–$200 for a separate test by a third party.

A working Colorado mitigation system should bring radon to under 2.0 pCi/L in most homes, often under 1.0. If the post-mit test reads above 4.0, the contractor should add another suction point or upgrade the fan under the performance warranty.

EPA recommends retesting your home every 2 years, even after mitigation. Three reasons:^[2]

• Soil-gas conditions change over time (settling, water table shifts, foundation aging).
• Fans degrade slowly. A fan that's bringing levels to 1.5 pCi/L now might be at 3.5 pCi/L in five years.
• Climate and seasonal patterns affect levels. A long-term retest averages across the year.

Beyond the 2-year cadence, retest:

• After major remodels that affect the foundation, basement, or HVAC.
• After adding new living space (finished basement, additions).
• If you notice manometer behavior changing.
• Before listing the home for sale (Colorado SB23-206 disclosure).

Keep this in a single folder with your home records. It becomes part of your required SB23-206 disclosure when you sell:

• Original radon test result (the one that triggered the install)
• Contractor's written quote and final invoice
• System certification from the contractor
• DORA license number, NRPP or NRSB certification number, contractor business info
• Fan model number and manufacturer warranty card
• Post-mitigation test result certificate
• Manometer baseline reading (the reading right after activation)
• All subsequent retest results
• Any service calls or fan replacements

Once a month, glance at the manometer when you're in the basement for any reason. You're checking for:

• The two fluid columns are at different levels (typically 0.5 to 2.0 inches of water column offset).
• The reading is reasonably close to what the contractor documented at activation.
• The fluid is still in the tube (occasional refilling may be needed; manometers don't usually leak in normal use).

What to do if the reading changes:

• Columns at the same level: Fan isn't running. Check the circuit breaker; call the installer if it's not a power issue.
• Reading much lower than usual: System is losing efficiency. Fan may be failing. Service call.
• Reading much higher than usual: Soil conditions changed (heavy rain, water table shift). Worth noting but rarely urgent.

The fan is the only routine maintenance item on a radon system. Most manufacturers warranty for 5 years; many fans run 7–10 years before replacement.

Signs of imminent fan failure:

• Audible humming, rattling, or grinding from the fan housing.
• Manometer reading dropping over time.
• A retest showing radon levels rising.
• Visible vibration of the fan.

Replacement cost: $150–$400 for the fan, plus 1–2 hours of labor. Most Colorado mitigators handle replacement as a service call rather than a full new install. If the original installer is unavailable (out of business, retired), any DORA-licensed contractor can do the replacement.