RESTAURANT WALK-IN FREEZER INSTALLATION
A local restaurant bought out an existing restaurant here in
town and was remodeling the interior and exterior of the building to suit their
needs. Part of our task was to install an indoor walk-in freezer in a back room
of the restaurant next to an existing walk-in cooler.
One of the most important factors in the installation of almost any piece of restaurant equipment that is sitting on the floor, especially a walk-in freezer,is to make sure the floor where it is going to sit is level.
So, the first thing we do is put a laser leveling device on the floor and make
sure we are dealing with a floor that is sufficiently level to install our box
on. I say "sufficiently" level because ideally the floor should be
perfectly level. However, few floors are ever perfectly level. If the floor is very
badly off level it may have to be repaired first. If it is slightly off we may
be able to use shims to level the box.
After checking this floor before installation we found it to
be real close to perfect (which you don't see too often) so we had a good floor
to begin our installation.
The existing walk-in cooler drain line and defrost timer
were mounted on the side where we needed to butt the new unit up against so we
had to disconnect and cut out the drain line on the old unit as well as remove
the wiring and defrost timer. Both the drain and defrost timer had to be
relocated so that the new walk-in could go next to the old one. We re-routed
the drain line in a different manner to the floor drain and reinstalled the
timer in a different location and rewired it to the electrical box and
evaporator.
The installers then brought in the new walk-in which comes
in panels that are positioned in place, installed and locked together to build
the box. Once the box itself is completely built the installers hang the evaporator
in the box and locate and mount the condensing unit on the roof above the
walk-in. Once the condensing unit is mounted and secured a 4" hole is made
in the roof for the penetration boot. The boot is then attached and sealed to
the roof so the refrigeration copper line set can run from the evaporator up into
the attic and out through the boot to the roof and connect to the condensing
unit.
The installer then seals the perimeter of the walk-in box,
removes all plastic wrap and labels, and cleans up the area.
At this point our refrigeration technician pipes the
interconnecting piping from the evaporator to the condensing unit, installs any
thermostat or TXV parts that may or may not be pre-installed, runs the drain
line, installs the drain pipe heater on the drain line if required, vacuums the
system to 500 microns, and wires the control wiring from the evaporator to the
defrost timer.
When all is ready the technician will check the thermostat,
defrost timer, and pressure controls for proper settings and perform a startup
on the system. After the system gets down near operating temperature he then
performs a superheat test to make sure it is operating at peak capacity.
Once the new freezer was operating and all checked out our
tech proceeded to start up and test the old cooler since we had moved the timer
and rewired it.
When our technician started testing the old cooler he found
the left side evaporator fan motor was stiff and seized up (store had been
closed and sitting for a while). After advising the owner the tech replaced the
evaporator fan motor and got the unit up and running again. After a while he
noticed it was struggling to cool down below 58-60 degrees F. Further checks
found a lot of frost only on and near the expansion valve. After placing his
refrigeration gauges on the unit he noticed the pressures were indicating what
looked to be a restriction, which coincides with the frosty expansion valve
that was noticed. Further superheat testing showed a high superheat number
which is also an indicator of a possible restriction. He attempted to open up
the expansion valve but no improvement was noticed. Therefore, he had to
recover the refrigerant, replace the TXV (expansion valve), vacuum the system
to 500 microns, and reinstall the charge. Since he replaced the expansion valve
he had to perform superheat adjusts on the new valve until the unit had a good
superheat setting. He set it at 8 degrees superheat. A good reading is
typically between 6-10 degrees superheat.
Once these repairs were made the cooler cooled down properly
and all problems seemed to be resolved.
Did you know we also do complete commercial kitchen design and consulting?
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