Rheem · Water heater
Code 24 Flow sensor fault
What this code means
The sensor measuring water flow through the unit isn't reporting correctly, which can prevent the unit from firing at all.
Most likely causes
- Debris lodged in the flow sensor
- Failed sensor
- Wiring connector fault
What to try first
Check the inlet filter for debris that could also be affecting the flow sensor housing.
Safety note: if this code returns after one clean reset, stop resetting it — repeated lockouts usually mean a real fault that needs a licensed technician. Never bypass a safety switch.
FAQ
What does Rheem error code Code 24 mean?
Flow sensor fault. The sensor measuring water flow through the unit isn't reporting correctly, which can prevent the unit from firing at all.
Can I fix Rheem code Code 24 myself?
Usually not. Check the inlet filter for debris that could also be affecting the flow sensor housing. If the code returns after one reset, it needs a licensed technician.
What causes Rheem code Code 24?
The most common causes are: debris lodged in the flow sensor; failed sensor; wiring connector fault.
Other Rheem water heater codes
All Rheem water heater error codes →
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This information may contain errors or not apply to your exact model — always double-check it against your appliance's own manual before acting. If there's any chance of a gas, fire, electrical, carbon monoxide, or other safety hazard, stop and call a licensed professional or the appropriate agency (e.g. your gas utility) instead of relying on this page alone.