Installation & Operation • 11
INSTALLATION & OpERATION
AIR CURTAIN VELOCITY
Air curtain velocity is affected by stocking levels, coil frost loads, temperature, and fan condition. Air velocity should be measured at the back
edge of the discharge air honeycomb, at the center of the middle door in the case (other doors have slightly lower velocity). A typical low temp
velocity reading is 400 to 500 feet per minute in a fully-packed low temp case, after the case has defrosted and pulled down to operating
temperature. Air curtain velocity in a partially-packed display case is significantly lower because more air exits the back wall duct holes. In fully
stocked medium temp cases, the velocity should be 300 to 400 feet per minute after the case has defrosted and pulled down to temperature.
Note: Indicated velocity can vary considerably from one velometer to another.
FAN REMOVAL
1. Turn off power to fans. Remove coil cover.
2. Unplug fan from fan power supply plug located on the front face of the fan housing.
3. Remove the fan blade nut and fan blade.
4. Remove the two mounting bolts and remove the fan assembly from the fan housing.
5. Remove the three fan motor mounting screws from the back of the fan motor.
6. Reverse steps 1 - 5 to install.
LED POWER SUPPLIES AND DRIVERS
LED Drivers for the Highlight
™
cases are located behind the kickplate in the electrical enclosure.
Refrigeration
Unless otherwise specified, the liquid and suction connections are made inside the case under the removeable evaporator fan/coil return air
grill bottom. Refrigerant piping may enter the case through the front left bottom, the left rear bottom, or the left rear top of case. The copper
pipe should not touch or rub on the edges of the sheet metal. After connections have been made, the refrigeration access hole in the case must
be sealed completely with an aerosol-dispensed urethane insulation or equivalent (e.g. GREAT STUFFf
™
). Penetrations made in sheet metal
baffles should also be sealed.
REFRIGERANT PIPING
Correct refrigeration line sizing and installation is essential for proper system operation.
,
and
for Highlight
™
cases.
Contact the factory for line sizing for the Highlight
™
cases. A P-trap must be
installed at the bottom of all vertical suction risers.
. Various risers are available as a factory-installed option. The
compressor should be installed as close as possible to the cases to reduce pressure drop. Install a shallow trap at the bottom of the riser.
When two or more case sections are connected to one compressor, the main liquid and suction line for the group should be run through the
cases and be brought out through the refrigeration outlet of one case only. The factory recommends one riser per circuit/system for hot gas
defrost when using top back refrigeration exit. Circuit risers are available as a factory-installed option. On 30" wide door cases with suction lines
over 1 3/8" diameter, a P-trap made with 45° elbows is required. A piping chase in front of the fan shroud allows the refrigerant lines to be run
through the right or left end frame.
Piping should not be placed near the electric defrost heaters. The defrost heaters on the 30" door cases will grow one inch to the left of the coil
when they reach operating temperature.
