Saunier-Duval-Thema-Classic-F24e-Installation-manual

16 Fault FindingTYPE OF FAULTNo display on control panelCHECK• 230V supply• PCB fuse• Connection between PCBsNo domestic hot water F24E Only)• Loose connections on control board (PCB)No central heating• Connections on air pressure switch (electrical or tubes)(Red flashing warning light and flashing disconnectedfault code in display)• Faulty control or interface board (PCB's)• Water pressure, flashing pressure• Shortage of air or gas• Faulty temperature sensor• OverheatingCOMPONENT TESTING DATACOMPONENT NORMAL MEASURE CHECKGas control valve Under demand during ignition sparks: If 0 Volt: the gas control valveResistance of coil 116 24V dc for 1 to 2 seconds, then is not faulty.12Vdc (constant) at the gas control If 24 Volts and then 12 Voltsvalve electrical connection.but no gas at the burner:Check if the gas control valve isstuck. If not, check theadjustment valve.Adjustment valve Close the gas inlet: If the valve does not move:(step motor) Dismantle the step motor (screw not Check the connections at bothsealed in). Trigger a demand and check motor and control board (PCB).that the valve opens during the ignition. Change the motor. Replace thecontrol board (PCB).(F24E Only)Three way valve. When heating is on: If voltages are different:Electrical supply to motor 230V ac between 1 and 2 of the motor. Connections.0 between 1 and 3. About 25V ac to 35V ac between 2 and 3. Control board (PCB).9.6k between 1 and 2. When hot water is on: Three way valve lead.9.6k between 1 and 3. 230V ac between 2 and 3 of the motor. 3 2 1(1, 2 and 3 marked on About 25V ac to 35V ac between 1 and 2.the motor).Thrust action of the motor. Unfasten the clip (YES, no risk of water If electrical supply is OK.(remove gas control valve leak), pull out the motor and leave it but the motor axle does not movebefore testing) plugged in. Replace the motor, or replaceWhen hot water is on: the spindle should the control board (PCB).pull in. When heating is on : the spindleshould push out.(F24E Only)Domestic water flowTo test: Use a new detector andconnect it electrically in place ofthe faulty one . Blow through tosimulate a demand for water.35 4000124050-2