Emerson Copeland Scroll ZP K3 Series - Low Ambient Cut-Out; Oil Type; Contaminant Control; Long Line Sets;High Refrigerant Charge

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© 2015 Emerson Climate Technologies, Inc.
AE4-1365 R4
pressures equalize. This condition does not affect
compressor durability but can cause unexpected
sound after the compressor is turned off.
Low Ambient Cut-Out
Because of internal discharge temperature protection,
a low ambient cut-out is not required to limit air-to air
heat pump operation. Air-to-water heat pumps must
bereviewedsincethiscongurationcouldpossiblyrun
outside of the approved operating envelope (Figure
1) causing overheating or excessive wear.
Oil Type
CAUTION
POE must be handled carefully and the proper
protective equipment (gloves, eye protection, etc.)
must be used when handling POE lubricant. POE
must not come into contact with any surface or
material that might be harmed by POE, including
without limitation, certain polymers (e.g. PVC/
CPVC and polycarbonate).
Polyol ester (POE) oil is used in these compressors.
See the compressor nameplate for the original oil
charge. A complete recharge should be approximately
four uid ounces (118 ml) less than the nameplate
value. Copeland
™
Ultra 32-3MAF, available from
Emerson Wholesalers, should be used if additional
oil is needed in the eld. Mobil Arctic EAL22CC,
Emkarate RL22, Emkarate 32CF and Emkarate 3MAF
are acceptable alternatives.
Contaminant Control
Copeland Scroll compressors leave the factory with
a miniscule amount of contaminants. Manufacturing
processes have been designed to minimize the
introduction of solid or liquid contaminants. Dehydration
and purge processes ensure minimal moisture levels
in the compressor and continuous auditing of lubricant
moisture levels ensure that moisture isn’t inadvertently
introduced into the compressor.
It is generally accepted that system moisture levels
should be maintained below 50 ppm. A lter-drier is
required on all R-410A and POE lubricant systems
to prevent solid particulate contamination, oil
dielectric strength degradation, ice formation, and
oil hydrolysis and metal corrosion. It is the system
designer’sresponsibilitytomakesurethelter-drieris
adequately sized to accommodate the contaminants
from system manufacturing processes that leave
solid or liquid contaminants in the evaporator coil,
condenser coil, and interconnecting tubing plus any
contaminants introduced during the eld installation
process. Molecular sieve and activated alumina are
twolter-driermaterialsdesignedtoremovemoisture
and mitigate acid formation. A 100% molecular sieve
lter can be used for maximum moisture capacity.
A more conservative mix of molecular sieve and
activated alumina, such as 75% molecular sieve and
25% activated alumina, should be used for service
applications.
Long Line Sets/High Refrigerant Charge
Somesystemcongurationsmaycontainhigher-than-
normal refrigerant charges either because of large
internal coil volumes or long line sets. If such a system
also contains an accumulator then the permanent
loss of oil from the compressor may become critical.
If the system contains more than 20 pounds (9 kg) of
refrigerant,itisourrecommendationtoaddoneuid
ounce of oil for every 5 pounds (15 ml/kg) of refrigerant
over this amount. This recommendation is a starting
pointifadditionaloilisrequiredandthenalamount
should be determined in the end use application.
Compressors with sight-glasses should have their
oil levels checked only when the compressor is off,
not while the compressor is running. If the system
contains an accumulator the manufacturer of the
accumulator should be consulted for a pre-charge
recommendation.
Other system components such as shell and tube
evaporatorscantrap signicant quantities of oiland
should be considered in overall oil requirements.
Reheat coils and circuits that are inactive during part of
thenormalcyclecantrapsignicantquantitiesofoilif
system piping allows the oil to fall out of the refrigerant
ow into an inactive circuit. The oil level must be
carefully monitored during system development, and
corrective action should be taken if the compressor oil
level falls below the top of the lower bearing bracket
for more than two minutes. The lower bearing bracket
weld points on the compressor shell can be used as a
low-oil-level marker.
Discharge Mufers
Flow through Copeland Scroll compressors is
semi-continuous with relatively low pulsation.
Because of variability between systems, however,
individual system tests should be performed to verify