What C3 Means
C3 is a long-fill fault — the unit isn't seeing water reach the expected level within its normal fill window.
Common Causes of C3
- Water supply valve partially closed
- Kinked supply line
- Failed water inlet valve
🔧 One Safe Check You Can Try
Check that the water supply valve under the sink is fully open, since a partially closed valve is a common, easy-to-miss cause.
⚠ Why You Shouldn't Go Further Than That
- If the supply valve is fully open and the line isn't kinked, the inlet valve itself needs testing, which is technician work.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.