Common problems guide

The most common Grant Euroflame Condensing problems

The faults most likely to send a Grant Euroflame Condensing into lockout — with plain-English causes, what to check first, estimated repair costs and whether you need a Gas Safe engineer.

This model is discontinued. Parts can be harder to source and expensive. If repair costs are mounting, a new A-rated boiler may be the smarter choice.
4 documented codes
4 most common
2 DIY-safe checks
2 engineer needed

The 4 most common faults

01
Lock-out High DIY-safe

Your boiler's safety system has switched the unit off because it is struggling to ignite or is not receiving enough fuel.

What to try first

Check your oil tank level to ensure you haven't run out of fuel.Inspect the oil supply valves to make sure they are fully open.Press the illuminated 'Reset' button on the burner once (if it fails to start after two attempts, call a technician).

Est. cost
£100-280
Parts
Fuel filter, Photocell, Oil pump
Full guide for Lock-out
02
Overheat High DIY-safe

Your boiler has become too hot and has automatically shut itself down to prevent damage or safety issues.

What to try first

Allow the boiler to cool down for at least 20 minutes.Locate the overheat reset button under the black screw cap on the control panel.Unscrew the cap and firmly press the small reset button until it clicks.Check that your radiator valves are open and the system pressure is correct.

Est. cost
£100-220
Parts
Overheat Limit Thermostat, Circulation Pump, Control Thermostat
Full guide for Overheat
03
10 Emergency Engineer

Your boiler is struggling to breathe because the exhaust pipe is likely blocked, causing smoke or fumes to leak out when it attempts to start.

Est. cost
£120-350
Parts
Chimney/Flue lining, Flue terminal, Burner gasket
Full guide for 10
04
12 Emergency Engineer

Your boiler is potentially leaking dangerous exhaust gases into your home because a cleaning panel or seal is not fitted correctly.

Est. cost
£90-180
Parts
Cleaning cover seal, Gasket kit, Combustion chamber insulation
Full guide for 12
Parts most often replaced

on the Grant Euroflame Condensing

Fuel filterPhotocellOil pumpNozzleOverheat Limit ThermostatCirculation Pump

Based on parts cited in our fault code database. Your engineer will confirm what's actually needed after diagnosis.

Call a Gas Safe engineer if…

  • You can smell gas or see signs of a leak
  • The Grant shows an Emergency or High severity code
  • The boiler keeps locking out after repeated resets
  • You've tried the DIY checks and the fault hasn't cleared
  • There's visible water leaking from the boiler
  • The flame is yellow or orange instead of blue
See the full 4-code list for the Grant Euroflame Condensing

Related guides

Boiler losing pressure → No hot water → When to replace → Symptom checker →