Amana ANX, Обслуживание и устранение неисправностей

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SERVICING
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Non-Condensables
If non-condensables are suspected, shut down the system
and allow the pressures to equalize. Wait at least 15
minutes. Compare the pressure to the temperature of the
coldest coil since this is where most of the refrigerant will
be. If the pressure indicates a higher temperature than that
of the coil temperature, non-condensables are present.
Non-condensables are removed from the system by first
removing the refrigerant charge, replacing and/or installing
liquid line drier, evacuating and recharging.
Checking Compressor Efficiency
The reason for compressor inefficiency is broken or
damaged scroll flanks on Scroll compressors, reducing the
ability of the compressor to pump refrigerant vapor. The
condition of the scroll flanks is checked in the following
manner.
1. Attach gauges to the high and low side of the system.
2. Start the system and run a “Cooling Performance Test. If
the test shows:
a. Below normal high side pressure.
b. Above normal low side pressure.
c.
Low temperature difference across coil.
d. Low amp draw at compressor.
And the charge is correct. The compressor is faulty –
replace the compressor.
Compressor Burnout
When a compressor burns out, high temperature develops
causing the refrigerant, oil and motor insulation to
decompose forming acids and sludge.
If a compressor is suspected of being burned-out, attach
a refrigerant hose to the liquid line dill valve and properly
remove and dispose of the refrigerant.
NOTICE
Violation of EPA regulations may result in fines
or other penalties.
Now determine if a burn out has actually occurred. Confirm
by analyzing an oil sample using a Sporlan Acid Test Kit,
AK-3 or its equivalent.
Remove the compressor and obtain an oil sample from the
suction stub. If the oil is not acidic, either a burnout has not
occurred or the burnout is so mild that a complete clean-up
is not necessary.
If acid level is unacceptable, the system must be cleaned
by using the clean-up drier method.
CAUTION
Do not allow the sludge or oil to contact the
skin. Severe burns may result.
NOTE: The Flushing Method using R-11 refrigerant
is no longer approved by Amana® Brand Heating-
Cooling.
Suction Line Drier Clean-Up Method
The POE oils used with R410A refrigerant is an excellent
solvent. In the case of a burnout, the POE oils will remove
any burnout residue left in the system. If not captured by
the refrigerant filter, they will collect in the compressor
or other system components, causing a failure of the
replacement compressor and/or spread contaminants
throughout the system, damaging additional components.
Install a field supplied suction line drier. This drier should
be installed as close to the compressor suction fitting as
possible. The filter must be accessible and be rechecked
for pressure drop after the system has operated for a
time. It may be necessary to use new tubing and form as
required.
NOTE: At least twelve (12) inches of the suction line
immediately out of the compressor stub must be
discarded due to burned residue and contaminates.
1. Remove compressor discharge line strainer.
2. Remove the liquid line drier and expansion valve.
3. Purge all remaining components with dry nitrogen or
carbon dioxide until clean.
4. Install new components including liquid line drier.
5. Braze all joints, leak test, evacuate, and recharge system.
6. Start up the unit and record the pressure drop across the
drier.
7. Continue to run the system for a minimum of twelve (12)
hours and recheck the pressure drop across the drier.
Pressure drop should not exceed 6 PSIG.
8. Continue to run the system for several days, repeatedly
checking pressure drop across the suction line drier. If the
pressure drop never exceeds the 6 PSIG, the drier has
trapped the contaminants. Remove the suction line drier
from the system.
9. If the pressure drop becomes greater, then it must be
replaced and steps 5 through 9 repeated until it does not
exceed 6 PSIG.
NOTICE: Regardless, the cause for burnout must be
determined and corrected before the new compressor
is started.