Vokera Synergy E Fault codes & diagnostics

14 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

System Natural GasLPG 24-29 kW 2008-2013 Discontinued
GC Number 41-311-84

Replaced by: Mynute i

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Severity at a glance

Each cell = one fault code. Hover to identify.
13 High 1 Medium
Just want the most common Vokera Synergy E faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 14 documented codes

Tap any card for details

01

Your boiler has tried to light but cannot find a flame, which is often caused by a temporary interruption in your gas supply or a blocked flue.

High DIY-safe £90-280

What to check first

  1. Check that your gas emergency control valve is open and you have credit on your gas meter.
  2. Verify if other gas appliances in your home, like a hob, are currently working.
  3. Press the 'Reset' button on the boiler control panel to attempt a restart.

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Printed Circuit Board (PCB)

Related codes

Full explanation for 01
02

Your boiler has reached an unsafe temperature because water isn't circulating properly through the system.

High DIY-safe £150-350

What to check first

  1. Wait for the boiler to cool down for at least 20 minutes.
  2. Ensure all radiator valves and any internal isolation valves are fully open.
  3. Press the Reset button on the control panel to clear the fault.

Parts commonly replaced

  • Circulation Pump
  • Overheat Thermostat
  • Main Heat Exchanger

Related codes

Full explanation for 02
03

Your boiler has detected a blockage or debris in its exhaust system which is preventing waste gases from being safely removed.

High Engineer only £90-180

Parts commonly replaced

  • Flue venturi
  • Fan assembly
  • Air pressure switch

Related codes

Full explanation for 03
04

Your boiler has detected that the water pressure is too low or there is trapped air in the system, preventing it from running safely.

High DIY-safe £0-120

What to check first

  1. Locate the filling loop (the flexible silver hose) underneath or near the boiler.
  2. Slowly open the valve(s) to let water into the system until the pressure gauge on the boiler reads between 1.0 and 1.5 bar.
  3. Close the valves tightly and check if the '04' code has cleared; you may need to press the 'Reset' button.

Parts commonly replaced

  • External filling loop
  • Pressure sensor
  • Automatic air vent

Related codes

Full explanation for 04
05

Your boiler is struggling to talk to your external remote control unit, meaning the two devices aren't sharing information correctly.

Medium DIY-safe £90-180

What to check first

  1. Check if the batteries in your remote control unit need replacing
  2. Ensure the remote control is within signal range of the boiler
  3. Turn the boiler power off at the fused spur, wait 30 seconds, and turn it back on to reset the connection

Parts commonly replaced

  • Remote Control Unit (RC05)
  • Wiring harness
  • Receiver interface

Related codes

Full explanation for 05
06

Your boiler's electronic control board has lost its configuration settings or has been set up incorrectly, preventing the system from operating.

High Engineer only £100-£350

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Jumper Tags

Related codes

Full explanation for 06
07

Your boiler has detected a fault with its temperature sensor, which means it cannot tell how hot the water is getting and has shut down as a safety precaution.

High Engineer only £90-160

Parts commonly replaced

  • NTC Temperature Sensor
  • Wiring Loom

Related codes

Full explanation for 07
08

Your boiler has shut down because a safety sensor detected that a internal component has become too hot.

High Engineer only £100-250

Parts commonly replaced

  • Burner thermostat
  • Heat exchanger
  • Main PCB

Related codes

Full explanation for 08
09

Your boiler's internal computer has encountered a critical error and can no longer control the heating system safely.

High Engineer only £250-£450

Parts commonly replaced

  • Main Printed Circuit Board (PCB)
  • Electrical wiring harness

Related codes

Full explanation for 09
10

Your boiler has detected an issue with the air pressure sensor or its connected hoses, meaning it cannot safely confirm that the fan is clearing exhaust fumes.

High Engineer only £120-240

Parts commonly replaced

  • Air pressure switch
  • Venturi tube
  • Fan assembly

Related codes

Full explanation for 10
20

Your boiler has detected a safety fault with the temperature sensors or internal wiring that prevents it from firing up.

High Engineer only £120-250

Parts commonly replaced

  • NTC Temperature Sensor
  • Wiring Harness
  • Main PCB
Full explanation for 20
30

Your boiler has detected an internal communication failure between its electronic control boards and has shut down for safety.

High Engineer only £180-350

Parts commonly replaced

  • Main PCB
  • Display Interface Board
  • Wiring Harness

Related codes

Full explanation for 30
40

Your boiler has stopped working because the water pressure inside the system has dropped too low.

High DIY-safe £80-150

What to check first

  1. Locate the filling loop (a flexible metal hose) underneath your boiler.
  2. Slowly open the valve(s) to allow mains water into the system until the pressure gauge reads between 1.0 and 1.5 bar.
  3. Close the valve(s) firmly once the correct pressure is reached.

Parts commonly replaced

  • Pressure relief valve
  • Pressure sensor
  • Expansion vessel

Related codes

Full explanation for 40
d1 & d2

Your boiler has stopped working because the pipe that carries waste water away is likely blocked or frozen, causing water to back up inside the unit.

High DIY-safe £80-160

What to check first

  1. Check the white plastic pipe outside for ice and pour warm (not boiling) water over it to melt any blockages.
  2. Ensure the end of the external pipe is not submerged in a drain or blocked by debris.
  3. Restart the boiler using the reset button once the pipe is clear.

Parts commonly replaced

  • Condensate trap
  • Condensate level sensor
  • External pipe insulation

Related codes

Full explanation for d1 & d2
Status & diagnostic codes

2 operating states & engineer diagnostics

Not faults — these are normal operating states. Tap to expand.

d1 Diagnostic Your boiler has stopped working because the waste water pipe is blocked, likely by debris or ice if it is cold outside. d2 Diagnostic Your boiler has detected an issue with the sensor that monitors the drainage of condensation water, which may prevent the unit from running safely.