Rinnai · Boiler
FFF Maintenance performed marker
What the control is telling you
Not a fault: FFF is a marker in the diagnostic code history showing that a service provider performed maintenance or service.
Applies to: I-Series Plus boilers — 150K BTU and smaller and 175K BTU and higher (Combi and Solo)
Likely causes
- Entered manually by a technician after servicing the boiler
- Indicates a service event in the code history
Test and repair steps
- After completing service, press UP, DOWN and DHW at the same time to log the FFF marker.
- Confirm FFF shows on the display.
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Source: Rinnai Troubleshooting I-Series Plus Boiler Diagnostic Codes (800000375), p.45. Summarized in our own words; check the original manual for your model.
Homeowner looking at this code? See what it means for you and when to call a technician.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.