E08

Dimplex Circulation Pump Fault

Boiler displays E08; pump symbol may flash; no circulation to radiators or cylinder

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

Seized Dimplex circulation pump, Air lock in Dimplex pump housing, Failed pump capacitor or motor, Blocked system filter restricting flow to pump

How to Fix / Troubleshooting

Safety first: Isolate electrical power and allow the system to cool before working near the pump.

Basic user actions:

Bleed air from pump: If accessible, use the bleed screw on the front of the Dimplex pump (if fitted). Place a cloth underneath, open the screw slowly until water appears, then close.
Check system pressure: Ensure the pressure is within the recommended range (around 1.0–1.5 bar cold). Low pressure can cause pump cavitation.
Reset the boiler: After bleeding and correcting pressure, reset the boiler and check if circulation resumes.

Professional repair:

Test the Dimplex pump for correct voltage and current draw.
Free a stuck rotor or replace the Dimplex circulation pump if seized or noisy.
Clean or replace any Dimplex system filter or magnetic filter to restore flow.

Repair Difficulty

Medium 3/5

Required Part

Dimplex circulation pump

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