6
Operating Mode Display:
•
Snowflake “ON” – compressor enabled in
run cycle; control displays current cabinet
temperature.
•
Snowflake “Flashing” – anti short cycle
delay enabled to protect the compressor
from trying to start too frequently.
•
Melting Snowflake “ON” – defrost in
progress, control displays the letters “dE”
•
Melting Snowflake “Flashing” – defrost
delayed by output activation setting.
•
Fan “ON” - Certain models that utilize the
XRO6 controller have the capability to
operate the evaporator fans on and off
independently from the defrost circuit.
•
To view the control’s programmed “Set
Point” (cut-out temperature): press and
release the “Set Key.”
•
To initiate a manual defrost cycle: press
and hold the “Manual Defrost Key” for
more than 3 seconds.
Note:
Manual Defrost will not initiate unless the
unit is at standard operating temperatures and the
evaporator probe is under the defrost termination
setting.
Electronic Control Operation:
The electronic control combines the functions of
both the mechanical thermostat and defrost timer
into a single control. The control also offers the
consumer the capability of monitoring the
operational status of the merchandiser via the icon
and digital temperature display (located on the
face of the control). The controller has been
programmed by Leer to operate the merchandiser
within the design parameters of the refrigeration
system. The set-point (cut-out) for these controls
has programmed parameters for 14-16°F, with a
differential of 6-8°F Should the user desire to alter
the Set-Point, the new set-points should not
/- 4° of the original factory setting. Do
not alter any of the programming parameters in
the controls without first consulting with Leer.
Auto-Defrost Control:
The AD control is located under the condensing
unit cover and contains two thermal-couple probe
wires. Both probe wires are routed through the
cabinet’s suction line hole and into the unit cooler
assembly, which is mounted to the interior ceiling
of the cabinet. The Red Air Sensing Probe (“P1”)
routes through the unit cooler and has its’ sensing
bulb secured to the outer, left-hand wall of the
unit cooler. Probe “P1” monitors the air
temperature in the merchandiser at that location.
During the normal operation of the control, the
digital display will show the cabinet temperature
at the probe “P1” location. The Black Probe “P2”
is inserted into the finned section of the
evaporator coil, near the top of the unit cooler
assembly. This probe monitors the temperature of
the evaporator coil during the defrost cycle.
Electronic Control Startup:
Turn the switch if equipped into the ON position
.
After a 2-minute delay, the compressor and the
condenser fan should start.
The light fixture
should start immediately when power is applied.
After a 2-minute delay, the compressor and the
condenser fans should start. The evaporator fans
will start once if the evaporator temperature is
under 75°F. The condensing unit will continue to
run until the air temperature in the cabinet reaches
+14-16°F.
Note:
If a defrost is required upon startup the
controller will enter defrost mode after the 2-
minute delay. Normal operation will resume upon
defrost termination and a short drip time.
Possible Displayed Alarm Codes:
“P1” – Air Probe failure: The control will
override the “P1” functions and cycle the
compressor at preset time intervals, until the
probe fault can be corrected.
“P2” – Evaporator Probe failure: The control will
override the “P2” function and operate with a
timed defrost cycle, until the probe fault can be
corrected.
“HA” – Maximum Temperature Alarm: The
cabinet air temperature has exceeded programmed
temperature for a period exceeding a preset time.
The alarm will continue to display until the
cabinet temperature drops below maximum levels.
