REFRIGERATION SERVICE
General:
••
Scotsman recommends that any work on the
refrigeration system only be done when it is
certain that the system needs repair.
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.
••
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.
••
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.
Note:
Only a HFC type dryer should be used.
••
When brazing the tubing connections to the hot
gas valve or TXV the component must be
protected by heat sink material.
Recover, Recover and Reclaim or Recover and
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 700-88. Reclaim programs are available
through most refrigerant wholesalers.
Access Valves: To use the access valves:
Remove the cap from the stem, use a 3/16" allen
wrench to check that the valve is CLOSED. Then
remove the core cap.
Close the valve and replace the caps when the
job is finished. The valve must be closed and
the caps must be on or the valve will leak.
If the refrigeration system must be serviced, the
quality of service must insure that there will
not be a repeat failure, as repeat failures will
cause refrigerant to be discharged into the air by
the failure or when the failure is corrected:
••
If there has been a compressor burn out, check
for acid in the oil. If acid is indicated, extra steps
must be taken to clean up the system.
••
Never use refrigerant to clean up or flush out a
refrigeration system. When system clean-up is
required, the use of suction line filter-dryers and
liquid line filter-dryers are recommended (they
must be compatable with polyolester oil and
HFC refrigerant).
••
Evacuate the system with a good vacuum
pump to 200 microns or less. If the triple
evacuation method is used, the vacuum should
be broken each time with dry nitrogen, not
refrigerant. Evacuation must be from both sides
of the system.
If an ice machine is to be discarded and still
contains refrigerant, Scotsman recommends that
the refrigerant be recovered, reclaimed, or
recycled so that it is not discharged into the air.
Torque Core
Cap to 7-12 ft. lb.
Torque Stem Cap
to 8-12 ft. lb.
Access Valves
Note: There are no Schrader
cores in the valve.
Allen
Wrench
Torque Stem
to 6-8 ft. lb.
CME250
October 1994
Page 24