Scotsman MAR1400 - Manual (Page 14)

Component Assembly
1. Install the ice chute.
2. Route the bin thermostat from its shipping
position on the control box to the ice chute.
3. Install the bin thermostat bulb in the ice chute.
MAR SPLIT UNIT - REFRIGERANT PIPING
CONNECTION
Fitting sizes:
Liquid Line Suction Line
3/8" 5/8"
Note: Connect the proper size tubing according to
the length of run. Runs longer than 10 feet will
require larger diameter tubing than these
connection sizes.
The MAR unit is shipped with a small holding
charge of R-404A. Recover this charge before
connecting the refrigeration tubing.
Take extreme care to keep refrigeration tubing
clean and dry prior to installation.
Following procedure should be followed:
a) Do not leave dehydrated compressor or
filter-drier open to the atmosphere any longer than
it is absolutely necessary. (One or two minutes
maximum suggested).
b) Use only refrigeration grade copper-tubing,
properly sealed against contamination.
c) Permanent suction line filter and liquid line
filter-driers are recommended in all field installed
systems.
d) When brazing refrigerant lines, an inert gas
must be passed through the line at low pressure to
prevent scaling and oxidation inside the tubing.
Dry nitrogen is preferred.
e) Line connections to vibration eliminators must
be made with silver solder alloy. Arrange that
refrigerant lines run along the walls and ceilings
and be supported at intervals frequent enough to
keep tubing straight and firmly in place. In all
cases the tubing should be run horizontally and
vertically with neat looking bends of as perfect
radius as possible.
The liquid line is not critical regarding its slope and
position, but the suction line must be installed so
the tubing will drain toward the compressor.
After all lines are connected, the entire system
must be leak tested.
The complete system should be pressurized to no
more than 11 atm (170 PSIG) with a trace of R-22
refrigerant and dry nitrogen for leak testing with an
electronic type leak detector.
For pressurizing, evacuating and charging the
system, two service valves are necessary; one
should be in the Suction Line at the inlet side of
suction filter and one should be in the Liquid Line
at the outlet side of filter dryer.
The two Service Valves, if properly capped, can be
left permanently in the system. Connection should
be 3/8" or 1/2" size.
WATER PIPING CONNECTIONS (PLUMBING)
The MAR is supplied with float valve that maintains
the water level in drum reservoir at the height
required for fresh water operation or if required, for
sea water operation. The water inlet line connects
directly to the float valve line fitting which is 3/4"
hose coupling thread, (copper tubing is not
recommended for sea water supply).
Note: An adapter fitting to go from 3/4” hose
coupling thread to 3/8” male flare is packed
inside the MAR unit.
Make sure to use a hand shut-off valve close
enough to MAR unit and a proper kind and size of
filter strainer.
Incoming water goes through the float reservoir
first and then to drum basin.
The drain water line should be shaped adequately
to drain by gravity any water passing through it.
Water drain fitting from float reservoir requires a 20
m/m I.D. (3/4” ID) water hose.
All plumbing connections should be made in
accordance with local plumbing codes.
MAR1400 & MAR2000
December 2000
Page 14