Hussmann MPCETNM6S, Руководство по установке и эксплуатации

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3-6
s
tart up
/ o
pEratIon
P/N 3086855_C
U.S. & Canada 1-800-922-1919 • Mexico 1-800-890-2900 • www.hussmann.com
1. The controller controls refrigeration tem-
perature. This is factory installed in the con-
trol panel. Adjust this control to maintain the
discharge air temperature shown. Measure
discharge air temperatures at the center of the
discharge louver.
Defrosts are time initiated and temperature
terminated for self contained. The defrost setting
is factory set as shown above.
To ensure a thorough defrost, defrost must be
terminated by the temperature termination
setting — not by time.
START UP
Follow the controller start up procedures as
detailed in Section 3 of this manual.
Each self contained merchandiser has its own
evaporator coil and a pre-set thermostatic
expansion valve (TEV). The TEV has been
factory set at design conditions to provide the
recommended performance.
TEV ADJUSTMENT
Expansion valves may be adjusted to fully feed
the evaporator. Before attempting to adjust
valves, make sure the evaporator is clear or only
lightly covered with frost, and the merchandiser
is within 10°F of its expected operating
temperature.
Adjust the valve as follows:
a. Attach a probe to the suction line near the
expansion valve bulb.
b. Obtain a pressure reading from the factory
installed Schraeder valve. Convert the pres-
sure reading to a saturated temperature for the
refrigerant.
Temperature (b) minus Temperature (a) is the
superheat. The valve should be adjusted so that
the greatest difference between the two tem-
peratures is 3°F to 5° F.
Make adjustments of no more than
1
/
2
turn of
the valve stem at a time and wait for at least
15 minutes before rechecking the probe tem-
perature and making further adjustments.
Model Product Application Discharge Air Temperature Defrost Frequency (per day) Type of Defrost Temp. Termination Failsafe Time (Minutes)
3
0 Medium Temp. (Dairy, Deli) 2
7
°F
6
Off-cycle
50
°F
MPCETN M 6S