Baxi Duotec+ GA Compact
37 fault codes documented
09 — Gas valve connection error
The boiler's electronic board is having trouble communicating with or controlling the gas valve. This can prevent the burner from operating.
10 — External probe sensor faulty
The external temperature sensor, which helps the boiler regulate heating based on outdoor conditions, is not working correctly. This can affect heating performance.
12 — Hydraulic differential pressure switch switching failure
The pressure switch in the hydraulic system is not operating correctly, possibly due to a problem with its contacts or the wiring. This is critical for boiler safety and operation.
13 — Hydraulic differential pressure switch contacts stuck
The contacts of the hydraulic differential pressure switch are stuck, preventing proper operation. This can lead to issues with water pressure detection and boiler function.
15 — Gas valve control error
The electronic board is unable to properly control the gas valve, which is essential for burner operation. This can prevent the boiler from heating.
18 — Hydraulic circuit automatic filling in progress
The boiler is currently undergoing an automatic filling cycle for the hydraulic circuit. This is a normal operation to maintain system pressure, not a fault.
19 — Fault in system filling phase
There is an issue occurring during the boiler's system filling process. This can prevent the boiler from reaching optimal operating pressure.
20 — NTC flow sensor faulty
The NTC flow sensor, which measures the temperature of the water flowing out of the boiler, is defective or has a wiring problem. This can affect temperature regulation.
28 — NTC fumes sensor faulty
The NTC fumes sensor, which measures the temperature of the exhaust fumes, is defective or has a wiring problem. This can be a safety concern.
40 — NTC return sensor faulty
The NTC return sensor, which measures the temperature of water returning to the boiler, is defective or has a wiring problem. This affects the boiler's ability to monitor system temperature.
50 — NTC domestic hot water sensor faulty (heating only model with storage boiler)
The NTC sensor for domestic hot water (DHW), used specifically in heating-only models with a storage boiler, is defective or has a wiring problem.
53 — Fumes outlet obstructed
The exhaust outlet for the boiler's fumes is blocked, which can prevent safe operation and lead to the boiler shutting down.
55 — Electronic board not calibrated
The boiler's electronic control board has not been properly calibrated, which is necessary for correct operation. This is usually an installer task.
83...87 — Communication problem between boiler board and control unit
There is an issue with the communication link between the boiler's internal electronic board and its external control unit (like an ambient unit or thermostat).
92 — Fumes fault during calibration (probable fumes recirculation)
A problem with fumes, possibly recirculation back into the boiler, was detected during the boiler's calibration process. This indicates an issue with the flue system.
109 — Air in boiler circuit (temporary fault)
There is air trapped within the boiler's heating circuit, which can interfere with water circulation and heating efficiency. This is often a temporary issue.
110 — Safety thermostat tripped due to overtemperature
The boiler's safety thermostat has activated due to excessively high temperatures, often caused by poor water circulation or air in the system.
117 — Pressure in hydraulic circuit too high (> 2.7 bar)
The water pressure in the boiler's hydraulic heating circuit is excessively high, exceeding 2.7 bar. This can be a safety concern and prevent operation.
118 — Pressure in hydraulic circuit too low (< 0.5 bar)
The water pressure in the boiler's heating circuit has dropped too low, below 0.5 bar. This prevents the boiler from operating safely.
125 — No circulation safety trip
The boiler has shut down due to a lack of water circulation, detected by a temperature sensor. This is a safety measure to prevent overheating.
128 — No flame
The boiler failed to detect a flame after attempting to ignite. This means the burner isn't lighting.
129 — Loss of flame at ignition
The boiler detected a flame during ignition but then lost it shortly after. This can indicate an unstable flame or a problem maintaining combustion.
130 — Fumes NTC tripped due to overtemperature
The fumes NTC sensor has detected an excessively high temperature in the flue system, causing a safety trip. This protects against dangerous conditions.
133 — Ignition failure (5 attempts)
The boiler failed to ignite after five consecutive attempts. This prevents operation and indicates a problem with the burner or gas supply.
134 — Gas valve blocked
The gas valve, which controls gas flow to the burner, is blocked or malfunctioning, preventing the boiler from receiving gas for ignition.
135 — Internal board error
An internal error has occurred within the boiler's electronic control board. This indicates a problem with the core electronics.
154 — Delivery/return probe control test
An issue related to the control test of the delivery/return temperature probes has been detected. This can affect the boiler's ability to accurately measure water temperatures.
160 — Fan fault
The boiler's fan is not operating correctly, which is vital for safe combustion and exhaust of flue gases. This is a safety-critical fault.
178 — Intervention of safety thermostat for excess temperature in low temperature system
A safety thermostat has tripped due to excessively high temperature within the low temperature heating system circuit. This is a safety shutdown.
270 — Overheating exchanger
The heat exchanger within the boiler has overheated, leading to a safety shutdown. This typically indicates a problem with heat dissipation.
317 — Incorrect power supply frequency
The boiler has detected an incorrect frequency in its electrical power supply. This can prevent proper operation and requires a stable power source.
321 — NTC domestic hot water sensor faulty
The NTC sensor responsible for measuring domestic hot water temperature is malfunctioning. This can affect the boiler's ability to provide hot water correctly.
384 — Parasite flame, internal error
The boiler's control system has detected a 'parasite flame,' meaning a flame is present when it shouldn't be, or is not being correctly detected. This is an internal control error.
385 — Input voltage too low (< 175V)
The boiler's electrical power supply voltage has dropped below 175V, which is too low for proper operation. The boiler should automatically reset once the voltage returns to normal.
431 — Exchanger sensor faulty
The sensor monitoring the heat exchanger is not functioning correctly. This can lead to incorrect temperature readings and affect boiler performance.
Display shows Fault symbol — Burner is prevented from lighting
A lightning bolt with a cross over it is displayed, indicating a general fault that is preventing the boiler's burner from igniting. This symbol can appear for various underlying issues.
Display shows water drop symbol — Boiler system water pressure low
The display shows a water drop symbol, indicating that the water pressure in the boiler's hydraulic heating circuit is too low. The boiler may stop working to protect itself.