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REFRIGERATION
Piping
The refrigerant line outlets are located under the case. Locate
first the electrical box, the outlets are then on the same side
of the case but at the opposite end. Insulate suction lines to
prevent condensation drippage.
Refrigeration Lines
Liquid
3/8" O.D.
NOTE: The standard coil is piped at
however, the store tie-in may vary depending
on the number of coils and the draw the
case has. Depending on the case setup, the
connecting point in the store may be
or 1
/
". Refer to the particular case you are
1
8
hooking up.
Refrigerant lines should be sized as shown on the refrigeration
legend furnished by the store.
Install P-TRAPS (oil traps) at the base of all suction line
vertical risers.
Pressure drop can rob the system of capacity. To keep the
pressure drop to a minimum, keep refrigerant line run as short
as possible, using the minimum number of elbows. Where
elbows are required, use long radius elbows only.
Control Settings
See CR3 technical data sheet for the appropriate settings
for your merchandiser. Maintain these parameters to achieve
near constant product temperatures. Product temperature
should be measured first thing in the morning, after having
been refrigerated overnight. Defrost times should be as
follows: OFF CYCLE - Defrost times should be as directed
in the CR3 technical data sheet. The number of defrosts per
day and the duration of the defrost cycle may be adjusted to
meet conditions present at your location.
Access to Thermostatic Expansion Valve (TEX) and
Drain Lines
Mechanical - Remove product from end of case. Remove
product racks. Remove refrigeration and drain access panels
(labeled). TEX valve (mechanical only) and drain are located
under each access panel at end of the case.
Electronic - The Electronic Expansion valve master and
slave cylinder(s) are located within the electrical access
panel(s).
Electronic Expansion Valve EEV (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.
Suction
5/8" O.D.
/
" (suction);
5
8
/
",
/
",
5
7
8
8
14
Thermostatic Expansion Valve Location
This device is located on the same side as the refrigeration
stub. A 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.
2. 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.
4. Subtract the saturation temperature obtained in step
No. 2 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 TEX Valve.
Service Case Temperature Control
Temperature control in the upper section of the CR3 with
the Service Option is done by means of a thermostat and
suction solenoid valve. This controls both temperature and
humidity.
Thermostat (T-STAT) Location
Thermostats are located within the electrical raceway. Refer
to diagram below. There are also labels on the back of the
case indicating T-STAT location(s).
Front Coils
controlled
by EPR
Valve
under
Deck Pan
T-Stat &
Ballast are
labeled as
such.
Optional
T-Stat and
Solenoid
(Right side)
Figure #3
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