Rev. 0608
13
electronic expansion valve (optional)
A wide variety of electronic expansion valves and case
controllers can be utilized. Please refer to EEV and
controller manufacturers information sheet. Sensors for
electronic expansion valves will be installed on the coil inlet,
coil outlet, and in the discharge air. (Some supermarkets
require a 4th sensor in the return air). Case controllers will
be located in the electrical raceway or under the case. The
front Self Service Evaporator has an EPR valve installed to
maintain a constant discharge temperature. It is located in
the front at the right side of the case under the fan plenum
near the TX valve.
thermostatic expansion valve location
This device is located on the same side as the refrigeration
stub. A Sporlan balanced port expansion valve model
is furnished as standard equipment, unless otherwise
specified by customer.
expansion valve adjustment
Expansion valves must be adjusted to fully feed the
evaporator. Before attempting any adjustments, make
sure the evaporator is either clear or very lightly covered
with frost, and that the fixture is within 10°F of its expected
operating temperature.
Measuring the operating Superheat
1. Determine the suction pressure with an accurate
pressure gauge at the evaporator outlet.
. From a refrigerant pressure temperature chart,
determine the saturation temperature at the
observed suction pressure.
3. Measure the temperature of the suction gas at the
thermostatic remote bulb location.
electrical
Refrigeration (cont'd)
wiring color code
CASE MUST BE GROUNDED
NOTE: Refer to label affixed to case to determine the actual
configuration as checked in the “TYPE INSTALLED”
boxes.
Electrical Circuit Identification
Standard lighting for all refrigerated models will be full
length fluorescent lamps located within the case at the
top.
The switch controlling the lights, the plug provided for
digital scale, and the thermometer are located at the rear
of the case mullion.
The receptacle that is provided on the exterior back of these
models is intended for computerized scales with a five amp
maximum load, not for large motors or other high wattage
appliances. It should be wired to a dedicated circuit.
electrical Service Receptacles (when applicable)
The receptacles located on the exterior of the merchandiser
are intended for scales and lighted displays. They are not
intended nor suitable for large motors or other external
appliances.
4. Subtract the saturation temperature obtained in step
No. from the temperature measured in step No. 3.
The difference is superheat.
5. Set the superheat for 5°F - 7°F.
evaporator Pressure Regulator
An Evaporator Pressure Regulator is installed in the front
of the self service section to maintain a constant discharge
temperature. It is located at the front right side of the case,
under the fan plenum near the TX Valve.
Service case temperature control
Temperature control in the upper section of the R3 with
the Service Option is done by means of a thermostat and
suction solenoid valve. This controls both temperature
and humidity.
t-Stat location
T-STATS are located within the electrical raceway. Refer
to diagram below.
T
-Stat &
Ballast
(Located in the
same place for
hot and cold)
Rear Storage
T-Stat and
Solenoid inside
Storage Area
Front Coils
controlled by
EPR Valve
under Deck Pan
(Right side)
