E11
Baxi Low Water Pressure / Pressure Switch Fault

Heater shows E11 and will not operate; may be associated with low system pressure on models with sealed primary circuits.

Advertisements

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.

Advertisements

Possible Causes

Low primary circuit pressure in Baxi sealed system, Faulty water pressure sensor or switch, Leak in primary circuit, Blocked pressure sensing tube

How to Fix / Troubleshooting

Safety: Allow the system to cool before topping up pressure. Do not over-pressurise.

Steps:

  • Check pressure gauge: On Baxi models with a sealed primary circuit, verify the pressure is within the recommended range (typically around 1.0–1.5 bar when cold). If low, top up using the filling loop as per the manual.
  • Inspect for leaks: Look around the heater and connected pipework for signs of water leakage.
  • Reset: After restoring pressure, reset the unit and observe operation.
  • Pressure sensor: If pressure is correct but E11 persists, the pressure sensor or switch may be faulty.

Professional: Replacement of the Baxi pressure sensor/switch and investigation of hidden leaks should be done by a technician.

Advertisements

Repair Difficulty

Medium 3/5

Required Part

Water Pressure Sensor / Switch
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements