Scotsman MAR1400 - Manual (Page 8)

Condensing Unit Component Control Devices
The scale-ice maker refrigeration system must
have certain safety devices and controls in order to
fully protect it, however an excess of automatic
controls and protections may complicate the
situation.
In order to help the installer to decide with which
controls to use, a description of typical controls
and their positive and negative points is listed
below.
High Pressure Control
Strongly recommended for a condensing unit. Set
to values shown on tech. spec.
Lo Pressure Control
Recommended for a condensing unit. Very
important because in case of refrigerant leaks at
the evaporator, it prevents the operation of the
machine when the evaporator is in a vacuum.
Operating the evaporator in a vacuum could draw
into the system water from the drum reservoir.
Vacuum could also cause air inflow through the
compressor crank-shaft seal.
However, it may trip-out at system start-up and if
the suction operating pressure is very close to the
cut out point, it may trip out then as well.
MAR1400 & MAR2000
December 2000
Page 8