Electra LEX 25 DCI Service Manual page 101

TROUBLESHOOTING
13.2.5.4 Checking the Outdoor Fan Motor
Check FAN-Power and FAN-Halls connections - Repair if needed.
Rotate the fan slowly by hand. If the fan does not rotate easily, check whether something is obstructing
the fan, or if the fan itself is coming into contact with the outer case, preventing it from rotating.
Correct if necessary - otherwise, the fan motor bearings have seized. Replace the motor.
If the fan rotates easily, use a current probe ("Clamp") to assure AC current on each phase and it is
less than 1A.
In case there is no current, check the resistance between the three poles. Assure the three coil
resistances are almost the same.
The normal value should be between 10Ω to 20Ω.
Change to Stand-by or Power OFF and re-start - If the fault is still active - replace controller.
13.2.5.5 Checking the Compressor
Check Compressor connections - Repair if needed.
Use a current probe ("Clamp") to assure that there is an AC current on each phase – no more than
15A.
In case there is no current, check the resistance between the three poles. Assure the three coil
resistances are almost the same (between 0.8Ω to 1.5Ω).
Change to Stand-by or Power OFF and re-start - If the fault is still "Active" - replace controller.
13.2.5.6 Checking the Reverse Valve (RV)
The RV has two parts, Solonoid and valve.
Solonoid - Running in heating mode, check the voltage between two pins of reverse valve connector,
normal voltage is 230VAC. if no power supply to RV, Check RV operation with direct 230VAC power
supply, if OK, replace outdoor controller.
Valve - if RV solonoid is OK (as above) but still no heating operation while compressor is On, replace
the valve.
13.2.5.7 Checking the electrical expansion valve (EEV)
The EEV has two parts, drive and valve.
When Outdoor unit is powered on, EEV shall run and have click and vibration.
For assuring the problem is of the EEV parts, perform the installation test and if fails and no other
indications in the diagnostics, than the problem is with the EEV (one or more).
Drive - a step motor; ringed on the valve. Check the drive voltage, should be12VDC.
Valve – if drive is OK (as above) but still the indoor unit perform no conditioning replace the valve (no
need to take out the refrigerant, just pump down and shut off the main valves).
13.2.5.8 Checking the termistors
Check Thermistor connections and wiring - Repair if needed.
Check Thermistor resistance – between 0ºC and 40ºC should be between 35KΩ and 5KΩ.
13.2.5.9 Checking the communication
Change to Stand-by or Power OFF and re-start - If the fault is still "Active" check Indoor to Outdoor.
Communication wiring and grounding connections (should be less than 2.0Ω) - Repair if needed.
If IDU failure – replace IDU controller that does not respond.
If ODU failure – replace ODU.
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CONTENTS
SM LEXDCI 1-E.1 GB