Water leaking from under the furnace or from boiler casing joints
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: Turn off power and, if leak is significant, isolate the boiler from the system and allow it to cool. Risk of scalding.
- Identify the source of the leak: check pipe unions, pump flanges, safety valve outlet, and drain valves.
- Tighten any slightly loose unions carefully; do not overtighten.
- If water is discharging from the safety valve outlet, check system pressure and expansion vessel charge.
- If water seeps from the boiler body or weld seams, the heat exchanger may be corroded.
Structural leaks in the boiler body require professional assessment; replacement of the heat exchanger or boiler may be necessary.
Repair Difficulty
Required Part
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