HUGE boiler savings!

Compare obligation-free quotes now!

  • All boiler models quoted
  • Trusted local boiler engineers
  • Latest May deals

New & Replacement

Save on new boiler installs!

  • Upgrades and new installs
  • Expert advice included
Get Free Quotes

Repairs & Servicing

Boiler maintenance for less!

  • Emergency repair work
  • Annual service savings
Get Free Quotes

Save on repairs now. Click!

2022 Trianco Boiler Error & Fault Codes


All Trianco boilers use error codes to communicate between the boiler and the user. These boilers alert you when there is a fault by a series of lights or even a set code displayed on the control panel. It is a simple but very effective way to alert you to a potential issue with the system.

The fault codes are useful because if one does occur, which is quite possible as the control will be checking for faults continually, it means that there is a problem with the boiler which needs to be looked at to make sure that it is safe to continue using. A check of the list below will show you what error codes are valid for your particular boiler and what they mean if they do occur.

Aztec Mini Combi, System & Classic Plus Boiler Fault Codes

Fault Code Protection Function Description
E2Current leakageMoisture on circuit board or the boiler has condensation internally
E3Water temperature sensorSensor is short circuit or open circuit
E5DHW temperature sensorSensor is short circuit or open circuit
E9Antifreeze faultHeating water temperature is too low
ECDisplay Disconnected with PCBDisplay Disconnected with PCB
F1Dry Fire ProtectionNo water flow
F4Low Water PressureSystem is low on water
F6No water FlowAir in the system, no water or water pump not working, pump is blocked, water flow switch blocked, water flow switch is faulty
External earth leakage protector trip (RCD)Display screen does NOT light up.
Dry burning temperature controller tripDisplay screen does NOT light up.
No heatingEquipment temperature does NOT rise.

Classic 2, 6, 9, 11 & 12KW Boiler Faults


If you find that your Trianco boiler is failing to start and there is no apparent reason, check the following:

If the green LED is NOT illuminated:

  1. Red LED on: get in contact with your local service engineer.
  2. Flashing red LED: Open circuit - the boiler is still operational though an engineer needs to be contacted.

Always check to ensure any external controls such as your thermostat or programmer/timer are actually requesting heating.

Free Boiler Quotes? Apply online now!

News Discover the latest boiler offers this May, get some free quotes!