⚠ Safety note: This guide involves working with plumbing. If you're not completely sure about every step, stop and call a licensed professional. Before you start, always switch off the power at the breaker or close the main water/gas valve.
1 Prepare a safe work area
Turn the system off at the controller, wait for the water and metal parts to cool, and read the manual for the exact model. If there is gas, smoke, or an electrical fault, stop immediately and call a licensed service technician.
⚠ Warning: Do not pump the vessel while the water side is under pressure, and do not close the safety valve. The wrong procedure can create dangerous pressure.
2 Track the cold-to-hot change
Record the pressure of the cold system and the maximum when heating. A fast rise and then drop after cooling is a typical sign of a vessel problem.
3 Check the safety valve and visible leaks
Look for signs of water at the valve drain and the connections. The valve can discharge water when a faulty vessel allows pressure to get too high.
4 Have a technician check the diaphragm and precharge
Accurate measurement requires the water side to be relieved. Water at the air valve usually means a ruptured diaphragm and a vessel replacement.
? Tip: Photograph the starting condition and change only one thing at a time. That way you will know which check actually affected the problem.
5 Reassemble, test, and set a limit
Restore the settings one by one and watch the temperature, pressure, sound, and any leak. If the values do not stabilize or the alarm returns, leave the system off and request a professional diagnosis.