Vaillant ecoTEC pro 24 Installation And Maintenance Instructions Manual

Also see for ecoTEC pro 24: Instructions for use Instructions for installation and servicing Instructions for installation and servicing Instructions for installation and servicing

Appendix0020244995_02 ecoTEC pro Installation and maintenance instructions 37Message Possible cause MeasureF.24 Safety switch-off: Temp.incr. too fastTemperature increase too fast ▶ Check: Plug, cable to the heating pump, air/insufficient waterin the heating circuit, internal air vent (function), heating pump(system pressure too low, temperature gradient too great onheating flow, non-return valve). Activate check programme P.0.F.25 Safety switch-off: Fluetemp. too highflue gas temperature too high ▶ Check: Plug, safety cut-out plug, cable harness, cable to theheating 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 checkprogramme P.0.F.26 Fault: Fuel valve notworkingGas valve assembly steppermotor 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: FlamesimulationMonitoring electrode reports anincorrect flame▶ Check: Gas pressure at upper test opening, monitoring elec-trode, PCB, gas solenoid valve.F.28 Start-up failure: Ignit.unsuccessfulFailure during start-up or igni-tion unsuccessful. Gas pressuremonitor or thermal cut-out hasbeen triggered.▶ Check: Gas stopcock, gas flow pressure, gas valve assembly,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.unsuccessfulGas supply interrupted intermit-tently. Re-ignition failed.▶ Check: Flue gas recirculation, condensate route (blockage),earthing, cable to the gas valve assembly and electrode (looseconnection).F.32 Fault: Fan Fan defective or not connected ▶ Check: Plug, cable harness, fan (blockage, function, correctspeed), Hall sensor, PCB, flue gas route (blockage).F.49 Fault: eBUS Undervoltage on the eBUS ▶ Check: eBUS (overload, two power supplies with different po-larities, short circuit).F.61 Fault: Fuel valve actu-ationThe gas valve assembly cannotbe actuated▶ Check: Cable harness, plug, gas valve assembly (rinse), PCB.F.62 Fault: Fuel valve switch-off delayDelayed switch-off sequence forthe gas valve after the flame isextinguished▶ 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-relevantsensor or cable defective▶ Check: Flow sensor, cable to the sensor, flame recordingsensor (e.g. ionisation electrode) for an unstable signal,electronics.F.65 Fault: Electronics temp. Electronics defective or too hotdue to external influences1. 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-stableFlame monitor reports an un-stable flame signal▶ Check: Air ratio, gas flow pressure, condensate route (block-age), gas injector, ionisation flow (cable, electrode), flue gasrecirculation.F.70 Fault: Invalid DeviceSpecific NumberIncorrect/missing DeviceSpecific Number orincorrect/missing coding resistor▶ If the display and PCB have been replaced, change the DeviceSpecific 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 differencebetween flow and returntemperature 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 reportsthat the water pressure is toolow▶ Check: Water pressure, earth connection, cable, plug, waterpressure sensor (short circuit to GDN).F.74 Fault: Water press.sensor (signal too strong)Water pressure too high ▶ Check: Water pressure (heating side, when heating pumpis not active), drain water if required, cable, water pressuresensor (short circuit to 24/5 V).F.75 Fault: Pump/ watershortageInsufficient pressure jump de-tected when starting the pump1. Check: Water pressure sensor, heating pump (blockage),heating circuit (air, sufficient water volume), adjustable by-pass, external expansion vessel (must be connected at thereturn). Activate check programme P.0.2. If a low loss header or heating pipes with a diameter greaterthan 1 1/2 inch are installed, replace the 3/4-inch seal in theheating flow with a screen. If required, install the F.75 serviceset.