A.O. Smith fault code C03
Fault code C03 on an A.O. Smith water heater (including ADMR) means: Reset error: too many resets in too short a period. Reset the appliance once. If the code comes back, a part is usually faulty. You can check the water pressure and settings yourself; leave work on gas-carrying parts to a certified gas engineer.
After a safety alert (gas, flue gas, combustion), reset no more than once and call in a certified gas engineer. If you smell gas, call your national gas emergency number or 112 immediately.
Cause
Fault code C03 on an A.O. Smith water heater indicates: Reset error: too many resets in too short a period.
Applies to
A.O. Smith ADMR, 115, 135, 50, 60, 80, 90, 40, BFC, 100, 120, 28, 30.
Fault code C03 on other A.O. Smith series
The same code does not mean the same thing on every series. Check the rating plate to see which series you have:
- C03 on Innovo, IR 12-160, IR 12-200, IR 20-160, IR 20-200, IR 24-245: Control fault: More than seven resets detected in a short period.
Matching parts
A.O. Smith parts are available from Instalpunt; shipping to EU countries from €17.95 (€24.95 for more distant countries), usually 3–5 working days.
This message does not point directly to one faulty part. These are the parts that most often fit this appliance:
- A.O. Smith anode 3/4" € 47.04
- A.O. Smith service gasket manhole € 56.19
- A.O. Smith sensor NTC assy € 57.50
Fix it yourself or call an engineer?
Always consult the manual for your appliance and work safely. If in doubt or if the fault comes back, call in a qualified professional. A question about a part? Write to us at info@instalpunt.nl.
Frequently asked questions
What does A.O. Smith water heater fault code C03 mean?
Reset error: too many resets in too short a period.
How do I fix fault code C03 on an A.O. Smith water heater?
First check the cause described above. Then restart the appliance using the reset button. If the message comes back, a part usually needs replacing or the fault needs to be repaired by a qualified professional.
Which parts do I need for A.O. Smith fault code C03?
That depends on the exact cause. In the A.O. Smith parts overview at Instalpunt you will find the current price and stock for each part.
Can I fix fault code C03 myself?
You can reset the appliance and check things like the water pressure or settings yourself. Work on gas-carrying parts must be left to a certified gas engineer.
All A.O. Smith water heater faults and codes at a glance →