Services & Maintenance/ Safety Consideration/ General Maintenance - Carrier CDII-184R1-0CTR4 Installation & Operation Manual

11 . Services & Maintenance
11.1 Safety considerations
Turn off all power to unit before servicing. Use field disconnects. Make sure that there are no parts
rotating and that discharge and liquid lines are cool.
DON'T TOUCH INVERTER DRIVE, WAIT FOR ATLEAST 6 MINUTES AFTER POWER SHUT.
Always use LOTO (Lock Out, Tag Out) procedure before any maintenance and service activity.
Do not overcharge, and never charge liquid into the low-pressure (suction) side of system. If the
system is charged through the suction side, the liquid refrigerant goes into the compressor and gets
mixed up with the compressor oil. When the compressor is on, this liquid refrigerant mixed with
compressor oil leads to compressor oil washout and further results in compressor failure.
11.2 General maintenance
Keep the units and area around the units clean.
Check the tightness of all bolts; nuts and screws correctly fastened hardware prevents damaging
vibration and eliminated leaks.
Ensure all insulations etc. are in place and in good condition.
Check protective devices are functional at set point. Check main switches and fuses. Tighten all
terminal connections.
From time to time, check that line voltage and phase unbalance is within specified limits.
Ensure mounting arrangement and base pan is intact and aesthetically & neatly installed.
11.2.1 CONDENSER AND EVAPORATOR COIL
Cleaning of coil is of utmost essence and should never be neglected. Cleaning of coils should
necessarily be done annually at the time of overhaul/ shutdown, or more often depending on working
conditions.
Clean condenser/ evaporator fins with a soft brush. If required, blow from inside with compressed air,
taking care not to damage fins. If the fins are dirty, clean using water or solvent. Protect amply the
electrical connections while chemical or water cleaning. However, use of water or solvent for cleaning
should be avoided as far as possible.
For assessing condenser coil for cleaning:
1. Turn off unit power supply.
2. Unscrew and remove top cover.
3. Clean the coil. After cleaning the coil, reassemble the unit.
For accessing evaporator coil for cleaning:
1. Turn off unit power supply.
2. Unscrew filter support bracket and remove the air filter.
3. Unscrew and remove base pan.
4. Clean the coil and after cleaning; reassemble the unit.
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