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IC.PS.600.A4.02 / 520B2809
© Danfoss A/S (IA-MC/mhe) 05-2007 / 520B2809IC.PS.600.A4.02 / 520B2809
Fault location
Symptom: Solenoid valve does not close/partly closes
Possible cause
Dirt in valve seat/dirt in armature
tube
Remedy
Components missing after valve
dismantling
Fit missing component(s)
1)
.
Valve installed wrong way round Check liquid ow direction and make sure the arrow is
pointing in the same direction.
Corrosion, pilot/main orice Replace defective components.
Clean valve; if necessary, replace defective components
Diaphragm upside down Check correct installation of valve
1)
Defective valve plate, diaphragm
or valve seat
Check pressure and liquid ow.
Replace defective component(s)
1)
.
Damaged/bent armature tube Replace valve.
Pulsation in pressure line.
Dierential pressure too high in
open position.
Pressure on outlet side periodically
higher than pressure on inlet side.
Check valve data.
Check pressure and liquid ow.
Replace valve with one more suitable.
Check rest of installation.
Manual opening unit cannot be
screwed back after use.
Check position of opening unit and adjust as necessary.
Dirt in or closed pilot orice/equa-
lising piece
Clean orice with needle or similar (max. dia. 0.5 mm).
Blow clean with compressed air.
If necessary, replace defective component(s).
Voltage remains on coil First lift coil slightly and note whether it oers
resistance.
Note: Never remove a coil with voltage applied - it might
burn out.
Check wiring diagram and wiring.
Check relay contacts.
Check lead connections.