User's Manual

System Maintenance
49 Liebert
®
MC
™
9.0 SYSTEM MAINTENANCE
9.1 General Procedures
• Model Number ________________
• Serial Number ________________
• Voltage / Phase / Frequency ________________
Periodic attention is necessary for continued satisfactory operation of your unit. Restricted air flow
through the condenser coil, reduced airflow from non-functioning fans and low refrigerant system
charge levels will reduce the operating efficiency of the unit and can result in high condensing
temperatures and loss of cooling. In winter, do not permit snow to accumulate around the sides or
underneath the condenser coil.
Monthly and semi-annual inspections and maintenance are recommended for proper system
operation. Use copies of 9.4.3 - Maintenance Inspection Checklist for each of these inspections.
If performance or operation problem are detected at anytime, refer to 8.2 - Premium Efficiency
Condenser Alarm Codes for required action.
9.2 Condenser Cleaning
Keeping the outdoor condenser coils clean is an important factor in maintaining peak efficiency,
reliability and long life of the equipment. The unit will operate more efficiently with frequent
cleanings. Delaying cleaning until heavy buildup occurs may create head pressure problems with the
evaporator units.
9.2.1 When to Clean the Condenser Coil
Normal conditions typically dictate cleaning twice a year, spring and fall. On-site or area conditions
such as cottonwood trees, construction, etc., can increase cleaning frequency. On your standard
monthly preventive maintenance schedule, Emerson recommends a visual inspection of the coil to
monitor conditions.
!
WARNING
Risk of electrical shock. Can cause injury or death.
Unit contains potentially lethal voltage in some circuits.
Disconnect all local and remote electric power supplies and wait 10 minutes before working in
the unit. The line side of the unit disconnect switch remains energized when the switch is in
the Off position. Use a voltmeter to make sure power is turned Off before making any
electrical connections.
Only properly trained and qualified personnel may perform repair, maintenance, and
cleaning operations.
!
WARNING
Risk of high-speed, rotating fan blades. Can cause injury or death.
The fan blades can start rotating without warning any time during a cooling cycle or after
power is restored after a power failure. Disconnect all local and remote electrical power
supplies to the unit, wait 10 minutes and verify with a voltmeter that the power is Off and
that all fan blades have stopped rotating before working on or near the fans.
NOTE
When ordering replacement parts for equipment, it is necessary to specify unit model number,
serial number and voltage. Please record those numbers in the spaces below.