Maxx Ice MIM1000, Руководство по обслуживанию

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3. Replacing the hot gas valve, drier and evaporator

Remove the top panel.

Locate the drier and hot gas valve, open weld, replace the drier and hot gas valve, weld, recover
refrigerant, evacuate and weigh in the charge on the nameplate.

Reverse the above steps to reassemble.

If needed, replace the evaporator.

Remove the front and top panels, locate the evaporator, open the Process/Suction, open the two
welds, replace with a new evaporator. Recover refrigerant, evacuate and weigh in the charge on the
nameplate.

Reverse the above steps to reassemble.
ADVANCED COMPONENT TROUBLESHOOTING TECHNIQUES
Refrigeration System
Refrigerant Cycle and Components
Before diagnosing the refrigeration system, it is very important that the refrigeration charge be
correct. Whenever the refrigeration system has been opened, the filterdrier must be replaced and the
proper refrigerant charge must be weighed in.
Refrigerant Pressures
The suction pressure at the beginning of the freeze cycle can vary +/10 psi (.7 bar) depending on
operating conditions. Pressures less than this may indicate an undercharge. The discharge pressure
on air cooled units will vary with ambient conditions.
Refrigerant in a gas state is pumped throughout the refrigeration system by a hermetic
compressor
to the condenser. Heat is removed from the refrigerant either by forced air movement through an
aircooled condenser or transferring heat from the refrigerant to water through a watercooled
condenser. The refrigerant changes to a liquid when cooled. The refrigerant in a liquid state passes
through a
filter drier.
The filter drier traps small amounts of moisture and foreign particles from the system. The filter
drier
must be replace whenever the refrigeration system is opened or if the refrigerant has been
completely lost.
Compressor
The compressor runs during the entire cycle. If the valves in the compressor are damaged, the
compressor will be unable to pump refrigerant efficiently. Damaged valves may be the result of
another problem in the refrigeration system such as liquid refrigerant returning to the compressor or
high head pressure. When a compressor is replaced it is important that the refrigeration charge be
weighed in and the system checked for proper operation to prevent a repeat failure.
An inefficient compressor will usually have a higher than normal suction pressure at the end of the
cycle. The freeze cycle will be longer than normal and/or the harvest cycle may be excessively long.
Check the compressor amperage draw 5 minutes into the freeze cycle. If the amp draw is less than
70% of rated full load amps, the compressor may be inefficient. These symptoms may also be
caused by other problems, therefore it is important to use the troubleshooting charts when
diagnosing a problem.
The air condenser is located in the back of the cabinet. Air is pulled through the condenser by a fan
motor and discharged through the right hand side panel. The Undercounter air intake and discharge
is through the front panel.
Do not block airflow as it will cause premature failure of the machine and will void the
warranty.