How to Fix / Troubleshooting

Safety first: Turn off power. Condensate is mildly acidic; wear gloves and eye protection.

Steps:

Inspect condensate trap: Remove, clean, and refit the Saunier Duval condensate trap, ensuring all seals are correctly positioned.
Check flue slope: Verify that the flue is installed with the correct gradient so condensate drains towards the heater or drain as specified.
Examine flue joints: Check all flue seals and joints for signs of water staining or leakage. Replace damaged seals.
Condensate collector: If the plastic collector at the base of the heat exchanger is cracked, it must be replaced.

Warning: Flue system integrity is critical for safety. If in doubt, have the flue inspected by a qualified technician.

Water heater leaks from the flue or top of the unit, especially on condensing models

Possible Causes