Location Considerations; Refrigerant Lines; Hydraulic Circuit; Ice Storage Room - Scotsman MAR 78 Service Manual

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LOCATION CONSIDERATION
WARNING - The MAR SCALE ICE MAKERS
are not designed for outdoors installations
where air temperature falls below 5°C
(40°F) and may exceed 40°C (100°F)
Operating a machine with an unacceptable
configuration will void the refrigeration system
warranty.
For installation on board of fishing vessels, the
location for the condensing unit is generally the
engine room, while the evaporator unit can be
permanently placed in some area of the deck-
house or if it is not too cold (not below 5°C), inside
the fish and ice hold.
In case a stand is going to be made and used plan
for adequately fastening the MAR SPLIT UNIT.
The stand must be steady made to do not cause
excessive vibrations and must have the possibility
to be securely fastened to the wall or to the floor.
In relation to evaporator position and situation a
certain kind of ice chute is required. Make sure to
have it available for the start-up of the system.

REFRIGERANT LINES

Inner diameter of refrigerant lines going from
condensing unit to evaporator unit and back,
must be of adequate size in relation to tubing
lenght.
The table below show the recommended sizes of
refrigerant lines:
MODELL Lenght of tubes Suction line Liquid line
MAR 78 5 to 15 mt
MAR 108 5 to 15 mt
MAR 128 5 to 15 mt
MAR 208 5 to 15 mt
MAR 308 5 to 15 mt
2. Insulate lines that will be exposed to outside
temperature that will be below freezing for
extended period of time.
3. Follow straight line routing, when possible,
however give to the suction line a certain pitch
(2 cm per meter).
On liquid line be sure to do not have restrictions.
Bends and fittings should be the minimum
necessary as they can increase the resistance
to the fluid flow.
4. To prevent any condensing unit vibration
travelling into the lines, vibration absirbers
may be installed in the suction and the liquid
lines near the condensing unit.
Because the appearence of an installation is
important, the piping should be put-in as
neathly as possible.
For best sound absorb-tion, it is best to put-in
two absorbers in each line, one vertically and
one horizontally.
18 mm 12 mm
18 mm 12 mm
18 mm 12 mm
28 mm 12 mm
42 mm 12 mm
For evacuation and charging operations two
service valves must be provided.
One on the liquid line and one on the suction
line.
5. A drier and a sight glass should be installed
in the liquid line at the condensing unit.

HYDRAULIC CIRCUIT

Another item that requires a preliminarly attenzion
for the MAR SPLIT installation is the water
supply to the ice making section and to the
condensing unit case a water cooled condenser
is being used. Separate water linea are
recommended with hand shut-off valve and water
filter on individual line.
Remember:
– Maximum Water Temperature
– Minimum Water Temperature
– Minimum Water Pressure
– Maximum Water Pressure
The Ice Making Section (MAR SPLIT UNIT)
generally requires:
– 21 lt/hr MAR 78
– 29 lt/hr MAR 108
– 42 lt/hr MAR 128
– 70 lt/hr MAR 208
– 91 lt/hr MAR 308
of constant water supply.
The water consumption of the water cooled
condenser (in case of water cooled condensing
unit) to be taken on account, with water inlet
temperature at 15°C is:
– 300 lt/hr MAR 78
– 480 lt/hr MAR 108
– 1200 lt/hr MAR 128
– 1500 lt/hr MAR 208
– 1600 lt/hr MAR 308
For installation on fishing vessels, using
seawater, to carry sea water from sea chest to
the condensing unit and to evaporating unit
through appropriate strainers, you may use
aluminium brass pipes or PHE plastic pipes to
avoid corrosion problems.
Never use copper tubes.

ICE STORAGE ROOM

Ice storage situations are of two kinds:
a) Short terms storage
b) Extended terms storage
Being, as stated scale ice made by MAR
machines flat, dry and subcooled, therefore with
the tendency to stick toghether, particular
attention is required for proper ice storage
conditions for better ice handling. An insulated
ice storage bin or room is always required, then
according to ice end use application, this can be
refrigerated or non-refrigerated.
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35°C
5°C
1 atm
5 atm