|Code||Message||Possible cause||Measure||Article Page / Link|
|F.00||Interruption: Flow sensor||Flow temperature sensor de- ▶ fective or not connected||Check: Flow temperature sensor, plug, cable harness, PCB.|
|F.01||Interruption: Return sensor||Return temperature sensor de- ▶ fective or not connected||Check: Return temperature sensor, plug, cable harness, PCB.|
|F.02||Interruption: DHW outlet sensor||Cylinder temperature sensor for ▶ the shift-load cylinder defective|
or not connected
|On the shift-load cylinder, check (only in conjunction with F.91): Plug, cable harness, temperature sensor.|
|F.03||Interruption: Cylinder sensor||Temperature sensor for the ▶ shift-load cylinder defective or|
|On the shift-load cylinder, check (only in conjunction with F.91): Temperature sensor plug, temperature sensor, PCB plug, cable harness.|
|F.10||Short circuit: Flow sensor||Flow temperature sensor de- ▶ fective or has short-circuited||Check: NTC plug, cable harness, cable/housing, PCB, NTC sensor.|
|F.11||Short circuit: Return|
|Return temperature sensor de- ▶ fective or has short-circuited||Check: NTC plug, cable harness, housing, PCB, NTC sensor.|
|F.12||Short circuit: DHW outlet sensor||Cylinder temperature sensor ▶ defective or has short-circuited||Check (only in conjunction with F.91): NTC plug, cable har- ness, NTC sensor, PCB.|
|F.13||Short circuit: Cylinder sensor||Warm start sensor/cylinder tem- perature sensor defective or not connected||1. Check: NTC plug, earth connection, cable harness, NTC sensor, PCB.|
2. Check the following on the shift-load cylinder (in conjunction with F.91): NTC plug, earth connection, cable harness, NTC sensor, connection to the PCB.
|F.20||Safety switch-off: Temper- ature limiter||Maximum temperature at the flow/return temperature sensor is too high when the safety cut- out function is operating using the NTC||Check:Flowtemperaturesensor(correctthermalconnection), cable harness, sufficient purging.|
|F.22||Safety switch-off: Low wa- ter pressure||No/insufficient water in the 1. product or the water pressure is|
|Check: Plug, cable to heating pump or water pressure sensor, water pressure sensor, heating pump.|
2. Activate and purge check programme P.0.
|F.23||Safety switch-off: Temp.spread too large||Temperature spread too great. Water circulation too low||Check:Plug,cabletoheatingpump/waterpressuresensor, air/insufficient water in the heating circuit, flow and return tem- perature sensor inverted, strainer in the hydraulic block, water pressure sensor, heating pump (sufficient circulation, level 2: D.19, D.14, non-return valve). Activate check programme P.0.|
|F.24||Safety switch-off: Temp. incr. too fast||Temperature increase too fast||Check:Plug,cabletotheheatingpump,air/insufficientwater in the heating circuit, internal air vent (function), heating pump (system pressure too low, temperature gradient too great on heating flow, non-return valve). Activate check programme P.0|
|F.25||Safety switch-off: Flue temp. too high||flue gas temperature too high||Check:Plug,safetycut-outplug,cableharness,cabletothe heating pump, internal air vent (function), flue gas route (block- age, adverse wind conditions, flue pipework too long), insuf- ficient water in heating circuit, heating pump, activate check programme P.0.|
|F.26||Fault: Fuel valve not work- ing||Gas valve assembly stepper ▶ motor defective or not connec-|
|Check: Gas valve assembly stepper motor (plug, cable, pas- sage for rinsing, voltage), multiple plug, cable harness.|
|F.27||Safety switch-off: Flame simulation||Monitoring electrode reports an ▶ incorrect flame||Check: Gas pressure at upper test opening, monitoring elec- trode, PCB, gas solenoid valve.|
|F.28||Start-up failure: Ignit. un- successful||Failure during start-up or igni- tion unsuccessful. Gas pressure monitor or thermal cut-out has been triggered.||Check:Gasstopcock,gasflowpressure,gasvalveassembly, air intake pipe (blockage, loosened screw), condensate route (blockage), multiple plug, cable harness, ignition transformer, ignition cable, ignition plug, ignition electrode, monitoring elec- trode, electronics, earthing, CO2 setting.|
|F.29 Operating failure: Ignit. unsuccessful||Gas supply interrupted intermit- ▶ tently. Re-ignition failed.||Check: Flue gas recirculation, condensate route (blockage), earthing, cable to the gas valve assembly and electrode (loose connection).|
|F.32 Fault: Fan||Fan defective or not connected||Check: Plug, cable harness, fan (blockage, function, correct speed), Hall sensor, PCB, flue gas route (blockage).|
|F.42 Fault: Coding resistor||Coding resistor or gas group ▶|
resistor causes a short circuit
|Check: Plug, earth connection, cable, output coding resistor (in the cable harness).|
|F.49 Fault: eBUS||Undervoltage on the eBUS||Check: eBUS (overload, two power supplies with different po- larities, short circuit).|
|F.52 Mass flow sensor not con- nected||Mass flow sensor defective or ▶ not connected||Check: Plug, cable harness, mass flow sensor.|
|F.53 Fault: Mass flow sensor||Mass flow sensor defective||Check:FilterbelowVenturifiltercapwetorblocked,gasflow pressure too low, internal pressure measuring point in the Ven- turi is blocked (do not use any lubricants on the O-ring in the Venturi).|
|F.54 Fault: Boiler start||No gas inlet pressure or insuffi- cient gas inlet pressure causes faults when the product is star- ted||Check(inconjunctionwithF.28/F.29):Gasstopcock,gasvalve assembly, plug, cable harness.|
|F.55 Fault: CO sensor||All-gas sensor defective or has ▶ short-circuited||Check: Plug, cable harness, all-gas sensor, PCB.|
|F.56 Safety switch-off: CO limit|
|Safety shutdown after the CO ▶ limit value is exceeded||Check: Gas valve assembly, plug, cable harness. If the fault occurs again after being cleared, the gas valve assembly is defective.|
|F.57 Fault: Measuring program||Regulation fault caused by cor- ▶ roded ignition electrode||Check: Ignition electrode, PCB (microcontrol).|
|F.61 Fault: Fuel valve actuation||The gas valve assembly cannot ▶ be actuated||Check: Cable harness, plug, gas valve assembly (rinse), PCB.|
|F.62 Fault: Fuel valve switch-off delay||Delayed switch-off sequence for ▶ the gas valve after the flame is extinguished||Check: Gas valve, surface of the burner (dirt), plug, cable har- ness, PCB.|
|F.63 Fault: EEPROM||EEPROM faulty||Replace: PCB.|
|F.64 Fault: Electronics/sensor||Electronics, safety-relevant ▶|
sensor or cable defective
|Check: Flow sensor, cable to the sensor, flame recording sensor (e.g. ionisation electrode) for an unstable signal, electronics.|
|F.65 Fault: Electronics temp.||Electronics defective or too hot 1.|
due to external influences
2. If required, reduce the environmental temperature.
|F.67 Fault: Electronics/flame||Implausible flame signal||Check: Cable harness, flame monitor, PCB.|
|F.68 Fault: Flame signal un- stable||Flame monitor reports an un- ▶ stable flame signal||Check: Air ratio, gas flow pressure, condensate route (block- age), gas injector, ionisation flow (cable, electrode), flue gas recirculation.|
|F.70 Fault: Invalid Device Spe- cific Number||Incorrect/missing Device ▶ Specific Number or|
incorrect/missing coding resistor
|f the display and PCB have been replaced, change the Device Specific Number under D.93.|
|F.71 Fault: Flow sensor||Flow temperature sensor re- ▶ turns implausible values||Check: Flow temperature sensor (correct thermal connection).|
|F.72 Fault: Flow/return sensor||Temperature difference ▶ between flow and return temperature sensor is too great||Check: Flow temperature sensor/return temperature sensor (function, correct thermal connection).|
|F.73 Fault: Water press. sensor (signal too weak)||Water pressure sensor reports ▶ that the water pressure is too|
|Check: Water pressure, earth connection, cable, plug, water pressure sensor (short circuit to GDN).|
|F.74 Fault: Water press. sensor (signal too strong)||Water pressure too high||1. Drain water|
2. Check the water pressure sensor.
|F.75 Fault: Pump/ water short- age||Insufficient pressure jump de- tected when starting the pump||1. Check: Water pressure sensor, heating pump (blockage), heating circuit (air, sufficient water volume), adjustable by- pass, external expansion vessel (must be connected at the return). Activate check programme P.0.|
2. If a low loss header or heating pipes with a diameter greater than 1 1/2 inch are installed, replace the 3/4-inch seal in the heating flow with a screen. If required, install the F.75 service set.
|F.77 Fault: Flue non-ret. valve/condens. pump||No flue non-return flap feed- ▶|
back; condensate pump over-
|Check: Cable to VR40 accessory, flue non-return flap (wiring, feedback switch), condensate pump, bridge from the surface-|
mounted thermostat, 2 in 7 multi-functional module (bridge).
|F.78 Interrupt.: DHW outlet sensor on ext. contr.||UK link box is connected without the domestic hot water temperature sensor being bridged||1. Check: Accessory (configuration/electrical connection).|
2. The unit displays a fault, but the unit has not malfunctioned.
|F.80 Fault: actoSTOR inlet sensor||Inlet temperature sensor defect-ive or not connected||▶ Check (only in conjunction with F.91): NTC sensor, plug, cable harness, PCB.|
|F.81 Fault: cylinder charging pump||Cylinder is not fully charged after specified time||Check(onlyinconjunctionwithF.91):Cylindercharging sensor, cylinder sensor, impeller sensor/limiter, prioritising diverter valve, pump, actoSTOR pump (air), cable harness, secondary heat exchanger (blockage).|
|F.82 Fault: Ext. current anode||External current anode defect-ive or not connected||Check: Cable harness, external current anode. If the external current ▶ anode is not installed: Plug edge connector X43 with a bridge into the PCB.|
|F.83 Fault: NTC temp. gradient||Temperature difference ▶ between flow and return temperature sensor is too small||Check: Flow/return temperature sensor (function, correct thermal connection), sufficient water volume.|
|F.84 Fault: NTC temp. diff. im- plausible||Temperature difference is im-plausible||▶ Check: Flow/return temperature sensor (correct thermal con- nection, sensors are inverted).|
|F.85 Fault: NTCs fitted incor- rectly||Flow/return temperat- ▶ ure sensors returning incorrect/implausible values||Check: Flow/return temperature sensor (correct thermal con- nection).|
|F.90 Fault: Communication||Communication with actoSTOR interrupted||1. Check: Plug, check cable harness to the actoSTOR module (PEBus).|
2. If the product is to be operated without an actoSTOR: Set D.092=0, if required, plug edge connector X31 into the BMU, if required plug edge connector X1 into the actoSTOR.
|F.91 Fault: actoSTOR sensor||Sensor on the actoSTOR is defective||▶ Check: Plug, cable harness, sensor.|
|F.92 Fault: Incorrect gas type||The coding resistor on the PCB does not match the gas group that is entered||1. Check: Coding resistor.|
2. Carry out the gas family check again and enter the correct gas group.
|F.93 Fault: Check gas route||Combustion quality outside the permitted range||Check:Gasinjector(suitableforthegasgroup),fluegasre- circulation, gas group, internal pressure measuring point in the Venturi (blockage). Do not use any lubricants on the O-ring in the Venturi.|
|F.94 Fault: Vortex and differen- tial pressure||Sensors return implausible values||▶ Check: Cable harness, plug, sensors.|
|LED actoSTOR Modul|
actoSTOR communication status
|actoSTOR communication status: Not connected, Con- nection error, Connection active||1. LED on: Communication OK.|
2. LED flashing: Communication not OK.
3. LED off: No power supply.
|Communicationfault||Communicationfaultbetweenthe display and the PCB in the|
Vaillant Fault Codes New
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