49
Packaged and Split Rooftop Ventilator
© 2021 Mitsubishi Electric US, Inc.
Premi
Sys
Routine Maintenance
DANGER
Electric shock hazard. Can cause injury or death.
Before attempting to perform any service or
maintenance, turn the electrical power to the unit to
OFF at disconnect switch(es). Unit may have multiple
power supplies.
CAUTION
Use caution when removing access panels or other
unit components, especially while standing on a ladder
or other potentially unsteady base. Access panels and
unit components can be heavy and serious injury may
occur.
This unit requires minimal maintenance to operate
properly. Maintenance requirements for this model
vary for each installation and depend greatly on how
much the system is used and the cleanliness of the air.
Proper maintenance will both increase the life of the
system and maintain its efficiency. Maintenance must be
performed by experienced technicians and in the case of
refrigeration systems, must be done by an EPA certified
technician.
Maintenance frequency is based on a presumed nominal
use of the system. If the system is being run constantly,
the frequency should be adjusted accordingly. If there
is seasonal debris in the air which can be drawn into
the filters and the coils, they should be checked more
frequently. If the system is being used for only a few
hours per day, the frequency may be reduced. Use the
maintenance log at the end of this manual to record
each maintenance session and observations and then
establish a maintenance schedule that is appropriate for
the installation. The following is provided as a guideline.
Maintenance Frequency:
Monthly
1. External Filter
Clean metal mesh filters
2. Internal Filters
Replace MERV 8 filters monthly.
Adjust replacement schedule for MERV 13 and
MERV 14 or other filters as inspection requires.
Semiannually
1. Check motor and motor bearings
Check for excessive heat, vibration or noise.
Lubricate bearings in accordance with the motor
manufacturer’s recommendations.
2. Condensate Drain (if applicable)
Inspect and clean – refill with water
3. Heat Transfer Coils (if applicable)
Inspect for cleanliness – clean as required
4. Outdoor Fan Blades and Motor (if applicable)
Check for cleanliness
Check all fasteners for tightness
Check for fatigue, corrosion, wear
Annually
It is recommended that the annual inspection and
maintenance occur at the start of the cooling season.
After completing the checklist, follow the unit start-up
checklist provided in the manual to ensure the
refrigeration system operates in the intended matter.
1. Lubrication
Apply lubricant where required
2. Dampers
Check for unobstructed operation
3. Blower Wheel and Fasteners
Check for cleanliness
Check all fasteners for tightness
Check for fatigue, corrosion, wear
4. Door Seal
Check if intact and pliable
5. Wiring Connections
Check all connections for tightness
6. Cabinet
Check entire cabinet, inside and out, for dirt
buildup or corrosion. Remove accumulated dirt,
remove any surface corrosion and coat the area
with appropriate finish.
