Vokera Boiler Error Codes - How To Fix
Written by Stephen Day
Gas Safe Engineer
Updated:
Familiarising yourself with common Vokera fault codes and their meanings can be crucial in swiftly addressing and resolving boiler issues, ensuring minimal disruption to your comfort.
Key takeaways
- Understanding Vokera boiler error codes enables swift problem identification.
- Homeowners can perform some initial troubleshooting steps for minor issues.
- Professional intervention by a Gas Safe-registered engineer is essential for technical faults.
Operating a Vokera boiler in your home means enjoying efficient heating and hot water-until an error code appears. These codes signify specific issues ranging from minor sensor faults to more severe problems requiring professional attention.
Familiarising yourself with common Vokera fault codes and their meanings can be crucial in swiftly addressing and resolving boiler issues, ensuring minimal disruption to your comfort.
Initial troubleshooting steps can often be taken by homeowners before seeking expert help. For example, a flashing red light indicates the system is in fault and lockout mode, typically due to a persistent issue that needs resolving to restore function.
Some issues, like a fan error indicated by code A03, are more technical and necessitate the assistance of a Gas Safe-registered engineer. It's imperative to address these faults promptly to prevent potential safety risks or further damage to the boiler.
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Gas Safe Engineers
While some error codes are straightforward enough to be identified and fixed by homeowners, we always advise contacting a Gas Safe engineer to assess the situation and carry out any repairs necessary.
All of iHeat’s engineers are fully qualified and Gas Safe, ensuring a swift and safe installation.
General Error Codes:
_St - Autostop
Indicates the boiler has automatically stopped.
_CL - Call for Service
A general alert to contact service personnel.
N/A - Flame On
Indicates that the flame is currently active.
P - Preheating Function Active
Shows that the preheating function is operational.
P Blinking - Preheating Function Running
Indicates the preheating function is in progress.
Hours - Stand-by
The boiler is in standby mode.
— - Off
The boiler is turned off.
A Series Error Codes:
A01 - Ignition Failure
The flame is not sensed, indicating an internal fault.
A02 - Limit Thermostat Fault
Problem detected with the limit thermostat.
A03 - Fan Fault
Indicates an issue with the boiler's fan.
A04 - Insufficient System Water Pressure
Water pressure in the system is too low.
A06 - DHW Thermistor Fault
Domestic hot water thermistor has an issue.
A07 - Primary Flow Thermistor Fault
Water temperature is excessively high.
A08 - Return Thermistor Fault
High temperature detected in return water.
A09 - Flue Thermistor Fault
Issue with the flue thermistor or its counter.
A11 - False Flame
Erroneous flame detection.
A77 - Low Temperature Thermostat Fault
Problem with the low-temperature thermostat.
Vokera Mynute Boiler Error Codes:
AL10, AL20, AL21, AL26, AL28, AL34
Suggests resetting the boiler; if persistent, contact a heating engineer.
AL40
Check and refill system pressure; reset boiler, contact engineer if persistent.
AL41
Similar to AL40, with emphasis on refilling and contacting an engineer if repeated.
AL52, AL55, AL60, AL71, AL73, AL74, AL79
Advises contacting a heating engineer.
AL74, AL79
Recommends a reset, and if the issue recurs, contact a heating engineer.
Evolve Combi Evolve System Error Codes:
E10 - Flame Lockout
Indicates a problem with flame detection or ignition.
E011 - Extraneous Flame
Detection of an unexpected flame.
E020 - Limit Thermostat
Issue with the limit thermostat.
E030 - Fan Fault
Problem detected with the fan.
E040, E041, E042 - Water Transducer Fault
Check system water pressure; indicates a transducer issue.
E060 - DHW Probe Fault
Issue with the domestic hot water probe.
4070 - Fault Flow Sensor Over Temperature
Indicates flow sensor issues or temperature differential alarm.
E077 - Main Zone Water Thermostat
Problem with the main zone water thermostat.
E080 - Return Line Probe Error
Issue with over temperature or differential alarm in the return line.
E090 - Flue Gases Over Temperature Probe
High temperature detected in flue gases.
E091 - Clean Primary Heat Exchanger
Indicates the need for cleaning the primary heat exchanger.
— - Water Pressure Low/High, Communication Lost
Indicate water pressure issues or loss of communication.
E021, E022, E023, E024, E067, E088, E097 - Iono Alarm
Potential ionisation issues.
E085, E094, E095 - Combustion Fault/High CO
Indicates combustion problems or high carbon monoxide levels.
E058 - Main Voltage Error
Issue with the main voltage supply.
E065 - Current Modulation Alarm
Problem with current modulation.
E086 - Obstruction Fumes Alarm
Alarm indicating obstruction in fumes exit path.
Additional Codes:
01 - Failure to Ignite
The boiler is unable to ignite.
02 - Overheat
The boiler is overheating.
03 - Fan/Flue Problem
Issue with the fan or flue system.
04 - Insufficient Water Pressure
Water pressure is too low.
05 - Reset as for Code 01
Advises reset similar to the failure to ignite.
06 - Hot Water Thermistor Open Circuit
Hot water thermistor has an open circuit.
07 - Primary Thermistor Open Circuit
Primary thermistor is open-circuited.
ADJ - Calibration
Indicates a need for calibration.
ACO - Service Operation
A service operation is in progress.
New Boiler Costs
Boilers can be a daunting purchase for many people as they’re an appliance with a lot of responsibility, providing heat for you and your family is something you want to get right. Boilers aren’t exactly a quickly disposable item either, potentially lasting you a decade.
Effectively, New boiler cost can be split into two segments: the first is the actual boiler itself (unit price), and the second is the cost of the boiler being installed (set up) in your property by an expert engineer.
Here at iHeat, we want to remove all of this undue stress and make the decision making process of upgrading to a new central heating system, as easy as possible.
Installation Type | Price (inc VAT) | |
Combi to combi swap | £1,845 | |
System to combi conversion | £2,499 | |
New boiler install | £2,899 | |
Back boiler to a combi | £3,299 | |
System to system | £1,945 |
Last updated:
Written by Stephen Day
Gas Safe Engineer at iHeat
Stephen Day is a Gas Safe registered and FGAS certified engineer with over 20 years of hands-on experience in the heating, cooling, and renewable energy industry, specialising in boiler installations, air conditioning, and heat pump systems.
LinkedInArticles by Stephen Day are reviewed by iHeat’s technical team to ensure accuracy and reliability.
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