Bosch tankless water heater vibrates excessively or rattles during operation

Safety first: Turn OFF power and gas before tightening hardware or adjusting components.

• Check mounting: Ensure all wall mounting screws are tight and anchored into solid framing. Add additional support if the wall is thin or flexible.
• Secure piping: Inspect water and gas pipes for contact with studs or other surfaces that can transmit vibration. Add pipe clamps and cushioning where needed.
• Vent support: Support long runs of vent pipe with proper hangers to prevent resonance and rattling.
• Fan inspection: If vibration seems to come from the combustion fan, have a technician inspect for imbalance, debris, or bearing wear.