Scotsman MAR 106, Руководство по обслуживанию

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If the stoppage is caused by its refrigerant
pressures or overloading in the compressor a
red light glows. Both controls that activate the
red lights are manual reset type controls,
therefore the cause of the stoppage should
be diagnosed and corrected before
reoperating the ice maker. J. Water Cooled Condenser
Tube within a tube condenser.
K. Water Regulating Valve
Penn made. Valve must be set to maintain
head pressure at 17 bar (240 psi) for
MAR 56-76, 15 bar (210 psi) for MAR 106-126,
16 bar (225 psi) for MAR 206 and 14 bar
(195 psi) for MAR 306.
L. Automatic Expansion Valve (A.E.V.) M.O.P.
The automatic expansion valve controls the
refrigerant when passing from the liquid line
to the evaporator. As the pressure decreases
on the low side, the expansion Valve open
and refrigerant escapes into the evaporator
drum channel where it absorbs heat from
water while evaporating. The valve maintains
a constant pressure in the evaporator coil
when the system is running indipendently of
the amount of refrigerant in the system.
This valve has an adjustment which may be
manually regulated to give the evaporator
coil the desired amount of refrigerant.
Turning the adjustment to the left,
counterclockwise, will increase the rate of
flow which is controlled by the pressure in the
evaporator.
When the compressor is not running the
valve will remain closed as the low side
pressure will be high enough to close the
expansion valve.
- MAR 56 -76 - 106 - 126 are generally equip-
ped with an expansion valve having an
orifice of 2,5 mm set for 3,0 bar of pressure.
- MAR 206 - 306 is also equipped with an
expansion valve having an orifice of 4,5 mm
set for 3.0 bar of pressure.
M. Evaporator Drum
Refrigerant inlet/outlet takes place on left
side journal.
The drum body is covered by a jacket in
special stainless steel resistant to the water
corrosion.
The front edge of the scraping blade must
have a clearance of minimum 0.05 mm from
cylinder metal jacket.
N. Refrigerant Seal System
Housed in the refrigerant inlet/outlet manifold
located on the evaporator drum left side
journal, is a leakproof joint. This joint is made
with seals that are carefully designed and
installed. The seals use two rubbing surfaces.
One surface tourns with the cylinder journal
and is sealed on it with on O ring of synthetic
material. The other surface is stationary and
fitted in its housing with leak-proof O ring.
The rubbing surfaces (optically flats) are made
of two different material that are: hardenend
steel for the rotating ring and graphite for the
stationary ring.