This could be caused by a range of factors:
1. The sensor rod could be too close to or touching the heating rod. Check the distance between the rods is at least 5mm.
2. The sensor rod is positioned above the heating rod in horizontal radiators. This would cause the sensor to overheat and cut out early. Check the position of the sensor rod by looking for the small black dot on the element neck.
3. The fluid levels could be too low (potentially due to loss during installation) which causes hot water to collect near the element, overheating the sensor. Confirm if any fluid was lost during installation and top up with appropriate replacement anti-freeze if needed.
1. The sensor rod could be too close to or touching the heating rod. Check the distance between the rods is at least 5mm.
2. The sensor rod is positioned above the heating rod in horizontal radiators. This would cause the sensor to overheat and cut out early. Check the position of the sensor rod by looking for the small black dot on the element neck.
3. The fluid levels could be too low (potentially due to loss during installation) which causes hot water to collect near the element, overheating the sensor. Confirm if any fluid was lost during installation and top up with appropriate replacement anti-freeze if needed.