Your boiler has lost track of the system's water pressure because the internal sensor is failing or disconnected, causing the unit to shut down for safety.

Water pressure sensor fault

What causes this fault?

This fault occurs when the boiler's internal computer can no longer read the water pressure inside the system. The most common reason is that the pressure sensor has developed an electrical failure or has become blocked with sludge and debris, preventing it from sending a signal. Because the boiler cannot confirm there is enough water to operate safely, it shuts down to prevent the unit from overheating.