Water dripping from the temperature and pressure (T&P) relief valve discharge pipe on an Ariston storage heater.
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: The T&P valve is a critical safety device. Do not cap or plug the discharge pipe. Turn off power if water is very hot or discharge is heavy.
- Check water pressure: Use a pressure gauge on a nearby tap. If static pressure exceeds manufacturer limits (often >6 bar), install or service a pressure reducing valve and expansion vessel.
- Test T&P valve: Lift the test lever briefly to flush debris, then release. If it continues to drip after a few minutes, the valve may be worn.
- Check temperature setting: Ensure the thermostat is not set excessively high. Overheating can cause frequent discharge.
- Replace T&P valve: Isolate water, relieve pressure, and drain below valve level. Unscrew the old valve, apply suitable thread sealant, and install a new Ariston-approved T&P valve. Reconnect discharge pipe and test.
If discharge continues after these steps, have a professional evaluate system pressure control and thermostat operation.
Repair Difficulty
Required Part
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