| 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 not connected | 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 sensor | 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 too low | 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- ted | 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 exceeded | 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 | Check: PCB. 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 low | 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- flow | 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 electronics box | ▶ Check:Cable/plugbetweenthedisplayandthePCB. |
Vaillant Fault Codes New
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