Scotsman AF300 User Manual page 25

Removal and Replacement: Refrigeration System
General:
Scotsman recommends that any work on the
refrigeration system only be done when it is certain
that the system needs repair.
Refrigerant should not be added except as a
way to determine the proper operation of the
product. If the system was low on refrigerant,
there is a leak, and it must be found and
repaired.
Refrigerant must not be wasted to the
atmosphere, but recovered.
This system has a critical charge, it must be
recharged with the correct amount of refrigerant
as listed on the nameplate of the ice machine,
or performance will suffer.
Anytime the refrigeration system has been
opened, the dryer should be replaced.
When brazing the tubing connections to the
thermostatic expansion valve, the component
must be protected by heat sink material.
If the air cooled condenser must be replaced,
the unit will have to be removed from its
installed location, and the back panel removed
to gain access.
Specifically:
Recover, reclaim or recycle refrigerant. The
method chosen is up to the service company.
There are various mechanical devices that may be
used to recycle refrigerant at the field level,
however, Scotsman requires that any refrigerant
placed into a Scotsman ice machine meet ARI
spec 700. Reclaim programs are available thru
most refrigerant wholesalers.
Use conservation minded service procedures:
Refrain from checking refrigeration pressures
without reason. There are many ways to
determine the proper operation of a Scotsman
ice machine without using refrigerant gauges.
Visual inspection of the water system,
observation of the ice formation, amp draw,
voltage, and other techniques will lead to proper
diagnosis. Scotsman also recommends that, at
the time of initial start up, gauges not be used.
If gauges must be used, do not always check
the high side pressure. If the condenser is clean
and seems to be operating correctly, it most
likely is. The low side pressure is much more
important on an ice machine than is the high
side.
If gauges must be used, use very short hoses.
Minimal refrigerant discharged into the hoses
equals minimal refrigerant discharged into the
air.
If using recycled refrigerant, it must meet ARI
spec 700 or have been cleaned by a machine
capable of attaining ARI spec 700. Removal
and Replacement: Refrigeration System
January 1993
Page 25
AF300