When Does a Backflow Preventer Need to Be Repaired vs. Replaced?

When Repair Is Appropriate

Most backflow preventers that fail an annual test can and should be repaired. Repair is appropriate when:

• The failure is due to a worn check disc, seat, or o-ring — standard repair kit components
• Debris is fouling a check valve seat and can be cleared or the module replaced
• The relief valve diaphragm has failed — a common repair on RPZ assemblies
• Test cocks are corroded but the body and internal components are sound
• The device is less than 15 to 20 years old with no history of major problems

When Replacement Is Appropriate

Replacement is recommended when:

• The device body is extensively corroded or cracked
• The device is no longer manufactured and repair kits are unavailable
• The device has repeatedly failed within a short period, indicating chronic deterioration
• The device is more than 20 to 25 years old, particularly in a high-mineral or aggressive water environment
• The device does not meet current code requirements for the hazard level it protects (e.g., a DCVA installed where an RPZ is now required)
• The device size is no longer appropriate for the current flow demand of the system

Cost Comparison

Repair kits for standard commercial backflow preventers typically cost a fraction of replacement, and repair includes retest to confirm the device passes. Replacement involves new material cost plus installation labor and a mandatory commissioning test. Our technicians will give you an honest assessment of whether repair is cost-effective for your device.