Fault rectification

Fault finding only by qualified electrician. Call on the services of a qualified electrician any time there is a fault. Repairs should only be carried out by a qualified electrician.

Switch off mains fuse, secure against being accidentally switched back on and position a warning sign.

Fault

Cause, measures

Fan does not switch on.

  • Start delay approx (max. 120 seconds). Wait for start delay and reduce if necessary.
  • No mains voltage. Check whether the mains fuse has failed. Switch on if necessary.
  • Impeller blocked. Should only be carried out by a trained specialist: Remove cover. Unlock internal grille or internal shutter via locking hooks. Check impeller and clean if necessary.

Fan does not switch off.

  • Overrun time (max. 25 min.). Wait for overrun time and reduce if necessary.

Motor’s thermal overload protection switches the fan off.

  • Motor too hot. Wait until the motor has cooled down. Cool-down time can be up to 10 minutes. Unit switches back on automatically after cooling down.

Lamellae do not open or close for K units.

  • Lamellae very dirty or blocked. Clean lamellae.
  • Check whether there are any objects between the lamellae. If so, remove them.
  • Check whether wiring is correct according to wiring diagram 1 (high level). Attach jumper between terminals 1 and 2.

Fan does not switch off or fan switches on when not wanted.

  • A high-impedance voltage is present at terminal L1 due to a glow lamp in the control switch, cables laid in parallel (induction) or transformers or other electrical components. Recommendation: Wire X2 capacitor (220 nF/ 250 V) to zero.