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Grant Boiler Fault Codes

23 fault codes · 25 models · 2 year warranty (standard)

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Grant Engineering is an Irish manufacturer of oil-fired boilers, founded in 1979. Their Vortex range of condensing oil boilers is extremely popular in rural UK and Ireland where mains gas is unavailable. Grant boilers are oil-fired (kerosene), not gas, so all fault diagnosis and repair must be carried out by an OFTEC registered engineer.

All Grant Fault Codes 23

Code Fault Severity Type View guide
BURNER LOCKOUT Burner Lockout The oil burner has gone to lockout — the red lockout light on the burner… High DIY Check View Guide
E01 Internal Control Fault The boiler's internal control electronics have detected a fault. High Engineer View Guide
E02 Flame Failure Flame lost during operation. High Engineer View Guide
E03 Fan Fault Fan not running correctly. High Engineer View Guide
E04 PCB Fault Internal PCB error. High Engineer View Guide
E05 Condensate Blocked Condensate blocked or frozen. Medium DIY Check View Guide
E06 Air Pressure Switch APS not confirming airflow. High Engineer View Guide
E07 Flue Gas Overheat Flue gas too hot. High Engineer View Guide
E08 DHW Sensor Fault Hot water sensor faulty. Medium Engineer View Guide
E09 Diverter Valve Fault Valve stuck. Medium Engineer View Guide
E10 Combustion Fault Combustion outside limits. High Engineer View Guide
EE1 High Pressure / Pump Failure / Airlock On Grant heat pump models, EE1 indicates high pressure caused by circulating pump failure or… High Engineer View Guide
EE2 Low Pressure The system water pressure is too low on Grant boilers. Low DIY Check View Guide
EE3 Overheat Protection Safety thermostat activated. High Engineer View Guide
EE4 Flow Sensor Fault Flow NTC sensor faulty. Medium Engineer View Guide
EE5 Return Sensor Fault Return NTC sensor faulty. Medium Engineer View Guide
NO FUEL No Oil Supply / Empty Tank The burner cannot obtain an adequate supply of oil fuel. The tank may be empty,… High DIY Check View Guide
OVERHEAT Overheat Thermostat Activated The boiler's overheat safety thermostat has tripped. On Grant oil boilers this usually means the… High Engineer View Guide
PP1 Flow/Return Temperature Sensor Fault The inlet (return) water temperature sensor has failed on Grant heat pump models. Medium Engineer View Guide
PP2 Pump Fault Pump not running. High Engineer View Guide
PP3 Low Water Pressure System pressure too low. Low DIY Check View Guide
RED LIGHT STEADY UV Sensor / Gas Valve Fault (Vortex Blue) On Grant Vortex Blue oil burners, a steady red light indicates the UV sensor is… High Engineer View Guide
SMOKE/FLUE FAULT Visible Smoke or High Smoke Number Black or grey smoke visible from the flue, or a high smoke number on combustion… High Engineer View Guide

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