Piper 3-CM - Manual (Page 9)

CLEANING CONDENSING UNIT (CM)
It is very important for proper performance and condenser longevity to keep the condenser clean.
EVERY MONTH:
A. DANGER: Disconnect electrical power to the cooler by turning master switch to the “OFF”
position and unplugging cooler from electrical receptacle.
B. Remove the louvered panels from the condensing unit compartment.
C. Clean condenser by using a brush and vacuum cleaner to remove all dust and dirt. Thoroughly
clean condenser. Wipe all surfaces of the condensing unit using a soft cloth or sponge with a
mild detergent. Rinse completely with warm water and then dry.
CAUTION: The fins on the condensing unit coils are sharp and may cause injury. Use care when
cleaning, gloves should be worn.
WARNING: Refrigerant is under high pressure. Do NOT bend, kink or damage any tubing or
condensing unit coil.
LUBRICATION (CM)
CAUTION: Make sure that master switch is "OFF" and disconnect the power cord from the
receptacle.
A. Remove the louvered panels form the condensing unit compartment. Grasp the louvered panel
at the bottom and pull straight out form the table to release from the magnetic catch.
B. Remove the rubber plugs from oil ports on the front and back of the condenser fan motor.
Apply a couple of drops of 10 weight machine oil to each oil port, do NOT over oil. Reinstall
rubber plugs into oil ports.
TEMPERATURE ADJUSTMENT (CM)
The temperature is adjusted by means of a low-pressure control device connected to the suction line of
the refrigeration system. The control is located in the condensing unit compartment and is mounted to
the false bottom of the sell near the rear of the condensing unit.
A thin straight blade screwdriver is required to make any adjustments.
A. Remove the louvered panels form the condensing unit compartment. Grasp the louvered panel
at the bottom and pull straight out form the table to release from the magnetic catch.
B. There are two adjusting screws located on the top of the control. The screw nearest to the side
of the control adjusts the differential (low temperature) and is pre-set at 18# and should only be
adjusted by a qualified service technician. The screw towards the center of the controls adjusts
the cut-in pressure (high temperature) and is pre-set at 23#. This results in the system starting
at a temperature of approximately 38° and shutting off at a temperature of 34°.