3-10
s
tart
U
p
/ o
pEratIon
P/N 0515957_M
U.S. & Canada 1-800-922-1919 • Mexico 01 800-890-2900 • www.hussmann.com
THERMOSTATIC EXPANSION VALVE
(TEV)
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.
