Heater is leaking water from the bottom of the cabinet
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Turn OFF power and gas. Shut off water flow to the heater if possible to prevent further leakage.
- Identify leak source: Remove the front and side panels and use a flashlight to trace the leak. Look at the inlet/outlet unions, header, and heat exchanger area.
- Tighten unions: If water is seeping from unions, gently tighten them by hand and then slightly with a wrench. Do not overtighten plastic unions.
- Inspect for cracks: Look for visible cracks in the heat exchanger or header. Green or white scale trails often indicate long-term leaks.
- Dry and monitor: After tightening, dry the area and restore flow to see if the leak persists.
Warning: A cracked heat exchanger or header usually requires replacement of the affected part or the entire heater. Do not operate the heater with active leaks.
Repair Difficulty
Required Part
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