Alpha E34 Fault

Alpha E34 Fault

The Alpha E34 error code indicates a low system pressure fault within the boiler. This condition occurs when the water pressure in the central heating system drops below the minimum level required for optimal operation. Low system pressure can affect the efficiency and functionality of the boiler, leading to issues with heating and hot water supply.

Causes of Alpha E34 Error Code

  1. Leaks in the Heating System: Even small leaks in the pipework, radiators, or boiler components can cause a gradual loss of water, leading to reduced system pressure.
  2. Bleeding Radiators: Releasing air from radiators can also lower the water pressure in the system if not subsequently topped up.
  3. Faulty Pressure Relief Valve: A malfunctioning pressure relief valve can release water unnecessarily, reducing system pressure.
  4. Recently Serviced or Repaired System: If the heating system was recently serviced or repaired, it might not have been repressurized correctly afterward.

Troubleshooting and Resolving the Alpha E34 Error Code

  1. Check for Visible Leaks: Inspect the boiler, pipework, and radiators for signs of leaks. Repair any leaks found to prevent further loss of pressure.
  2. Repressurize the System: Use the boiler’s filling loop to repressurize the system to the manufacturer’s recommended level (usually between 1 and 1.5 bar). Consult the boiler manual for specific instructions.
  3. Bleed Radiators: If air is trapped in the radiators, carefully bleed them to remove air, and then recheck and adjust the system pressure as necessary.
  4. Check the Pressure Relief Valve: Inspect the pressure relief valve for signs of malfunction, such as continuous dripping from the discharge pipe. A faulty valve should be replaced by a professional.
  5. Reset the Boiler: After addressing the low pressure issue, reset the boiler to clear the error code and reinitiate normal operation.
  6. Professional Assistance: If you’re unable to identify the cause of the low pressure or if the E34 error persists after taking corrective action, seek help from a Gas Safe registered engineer. They can perform a comprehensive system check to identify and fix underlying issues.
  7. Regular Maintenance: Prevent future occurrences of the E34 error and other issues by ensuring your boiler and heating system receive regular professional maintenance. This can help identify potential problems early, keeping the system running efficiently and safely.


The Alpha E34 error code is a clear indication of low system pressure, necessitating prompt action to identify and rectify the cause. While homeowners can perform basic checks and repressurize the system, some conditions, especially leaks or faulty components, may require professional repair. Regular maintenance is crucial for preventing pressure-related issues and ensuring the longevity and reliability of your heating system.