Southbend 20108RSB - Manual (Page 6)

6 Printed in USA 12/02 Refrigerated Base-Remote © 2002
SCHEDULED MAINTENANCE
INTRODUCTION
To ensure the longest and most trouble free operation of the
unit, a thorough maintenance schedule is required to be
adhered to periodically. The maintenance system should
be designed to maximize the efficient use of maintenance
personnel, reduce down time, and provide the orderly
acquisition of spare parts support.
The Middleby refrigeration cabinet will generally be in
operation in a facility where scheduled maintenance is
performed according to Maintenance Index Plans. Your unit
is no exception to required maintenance. This section of the
manual is intended as an alternative to any standard
maintenance program that may pre-exist. The preventive
maintenance schedule is based upon similar maintenance
requirements for commercial refrigeration equipment.
PREVENTIVE MAINTENANCE ACTION INDEX
If you do not have a Maintenance Index Plan, one is included
for you in Table 4.1.
PREPARATION FOR MAINTENANCE
Since many areas affected by the maintenance schedule are
electrically supplied, it is recommended that the system be
de-energized prior to making the inspections.
MAINTENANCE
Weekly Inspection
1. The unit should first be de-energized.
2. Using a vacuum or small hand broom, brush the
condenser in a vertical motion to remove any dust or
debris that may have accumulated.
Monthly Inspection
1. Check the evaporator drain line at both the inlet
and outlet ends to make certain that there are no
obstructions. It is not recommended to use any
chemicals in clearing a clogged drain. The preferred
method of unstopping an obstructed drain is to use
compressed air. Approximately 60 lbs. should be
sufficient. Simply remove the drain line at the
evaporator coil and attach an air-line to it.
2. With the unit in a cooling cycle, use a flashlight and
locate the refrigerant sight glass i . If the compressor
has been running for three minutes there should be no
visible bubbles.
3. If bubbles are present:
a. Determine if there is a leak by using a halide or
electronic leak detector.
b. Repair leak(s).
WARNING
The system should be de-energized when checking
for leaks.
i. If a leak is found on a flared fitting, it can often be
repaired by simply tightening the brass flare nut 1/4
of a turn. If tightening does not repair the leak, it
may be necessary to reflare the tubing.
ii. If a leak is found on a brazed joint, it will be
necessary to pump down the system’s refrigerant
charge to remedy the problem.
iii. To pump the refrigerant into the receiver, you must
first connect service gauges to the system at the
suction valve on the compressor and the liquid valve
on the receiver. Purge the gauges before opening
the system’s valves to avoid contamination. Run the
receiver (liquid or high pressure) valve all the way in
to stop the refrigerant from exiting the receiver.
Start the unit and allow it to run until the suction or
low-pressure gauge reads 5 lbs. When it reaches
5 lbs., de-energize the system.
iv. Once pumped down, the necessary repairs can be
made.
4 Using a mild non-abrasive detergent and soft cloth,
wipe the interior lining beginning with the top and
working down. Also, wipe the gasket and where it sits
on the cabinet exterior.
5. Check the condenser fan motor and make certain that
it is not loose. Inspect the fan for cracks and make
sure that it is tight on the motor
i .
6. To inspect the evaporator motor, first turn the unit off.
Then, remove the drain line from the evaporator pan.
Loosen the four screws that hold the shroud. Lower
the shroud and disconnect the polarized electrical
connection. With the shroud out of the cabinet,
proceed to inspect the motor mounting bolts and the
fan for cracks or excessive play.
7. Using a mild detergent and water, wipe the vinyl
gasket. Make certain to also clean under the gasket
to remove any mildew or residue.
8. Using a mild, non-abrasive detergent and warm water,
wipe the cabinet exterior. When cleaning always follow
the grain of the stainless steel to prevent scratching
or marring of the finish surface.