40
UNIT COOLERS
QUARTERLY
SEMI-ANNUALLY
DATE
DATE
DATE
DATE
Visually inspect unit
4
4
1
Look for signs of corrosion on fins, cabinet, c
opper tubing and solder joints
4
4
2
Look for excessive or unusual vibration for fan blades or sheet metal panels when in operation.
Identify fan cell(s) causing vibration and check motor and blade carefully.
4
4
3
Look for oil stains on headers, return bends, and coil fins. Check any suspect areas with an
electronic leak detector.
4
4
4
Check drain pan to insure that drain is clear of debris, obstructions or ice build-up and is free draining.
4
4
5
Insure that there is sufficient clearance free of obstructions around unit coolers to allow proper airflow through coils
4
4
6
Verify Box setpoint temperature is being met
4
4
Clean Evaporator coil and blades
4
1
Periodic cleaning can be accomplished by using a brush, pressurized water or a commercially available Evaporator Coil Cleaner or mild detergent.
Never
use an acid based cleaner. A
lways
follow label directions for appropriate use. Be sure the product you use is approved for use in food service applications.
4
2
Flush and rinse coil until no residue remains.
4
3
Pay close attention to drain pan, drain line and trap.
Check the operation of all fans and ensure airflow is unobstructed
4
1
Check that each fan rotates freely and quietly. Replace any fan motor that does not rotate
smoothly or makes an unusual noise.
4
2
Check all fan set screws and tighten if needed.
4
3
Check all fan blades for signs of stress or wear. Replace any blades that are worn, cracked or bent.
4
4
Verify that all fan motors are securely fastened.
4
Inspect electrical wiring and components
4
1
Visually inspect all wiring for wear, kinks, bare areas and discoloration. Replace any wiring found to be damaged
4
2
Verify that all electrical and ground connections are secure, tighten if necessary.
4
3
Check operation/calibration of all fan cycle and defrost controls when used.
4
4
Look for abnormal accumulation of ice patterns and adjust defrost cycles accordingly
4
5
Compare actual defrost heater amp draw against unit data plate. (freezer only)
4
6
Visually inspect heaters to ensure even surface contact with the coil. If h
eaters have creeped
decrease defrost termination temperature and be sure you have even coil frost patterns. (freezer
only)
4
7
Check low voltage wiring at Beacon board for broken wires
4
8
Check voltage at Beacon board. Should be between 18 to 30 Volts
4
Check Beacon sensors
4
1
Press MONITOR button to display sensor reading for Box Temp., S
uction Temp. and Defrost Temp.
4
2
Use an accurate Thermometer to measure temperatures at the same locations as the sensors.
4
3
LED readings should match measured values, within 3 °F at same locations as sensors.
4
Check Beacon Pressure Transducer
4
1
Press MONITOR button to display Suction Pressure reading at the Evaporator
4
2
Use an accurate Gauge Set to measure Evaporator Pressure.
4
3
Measured suction pressure should match LED displayed value within 2 Psig.
4
Check Drain Line Heater
4
1
Check heater amps
4
2
Check that heater is wrapped around entire length of drain line inside the walk-in freezer
4
Refrigeration Cycle
4
1
Check unit cooler superheat and compare reading for your specific application
4
2
Visually inspect coil for even refrigerant distribution
4
Preventive Maintenance