SERVICING
32
b. If subcooling is low and superheat is 7 to 9°F, add charge
to rise subcooling to 8°F ± 1°F, then check superheat.
c. If subcooling is low and superheat is high, add charge
rise subcooling to 8°F ± 1°F, then check superheat.
d. If subcooling is 8°F ± 1°F and superheat is high,
adjust the TXV valve to 7 to 9°F superheat, then
check subcooling.
e. If subcooling and superheat are high, adjust the TXV
valve to 7 to 9°F superheat, then check subcooling.
f. If subcooling is high and superheat is 7 to 9°F, re-
move charge to lower the subcooling to 8°F ± 1°F,
then check superheat.
g. If subcooling is high and superheat is low, adjust the
TXV valve to 7 to 9°F superheat and remove charge
to low the subcooling to 8°F ± 1°F.
h. If subcooling is 8°F ± 1°F and superheat is low, ad-
just the TXV valve to 7 to 9°F superheat and re-
move charge to lower the subcooling 8°F ± 1°F, then
check the superheat.
NOTE
: Not more than 0.5 lb. (8 Oz.) of refrigerant
must be added to the system in order to achieve the
target subcooling. It is recommended to add 4 oz.
refrigerant each time and try adjusting the TXV and
let the system stabilize.
4. Disconnect manifold set. Installation is complete.
SUBCOOLING ADJUSTMENT ON EEV APPLICATIONS
NOTE
: Subcooling information is valid only while the unit
is operating at 100% capacity or 100% compressor speed
in CHARGE MODE. Compressor speed is displayed under
STATUS menu in the thermostat.
1. Run system at least 20 minutes to allow pressure to
stabilize. During the adjustment of subcooling, ambient
temperature should be greater than 65°F and less than
105°F. If ambient temperature is out of range, don’t a
just subcooling.
2. For best results, temporarily install a thermometer on
the liquid line at the liquid line service valve. Ensure the
thermometer makes adequate contact and is insulated
for best possible readings. Use liquid line temperature to
determine sub-cooling.
3. The system subcooling should fall in the range shown
in following table. If not in that range, adjust subcooling
according to the following procedure.
a. If subcooling is low, add charge to adjust the sub-
cooling to 8°F ± 1°F.
b. If subcooling is high, remove charge to lower the
subcooling to specified range.
NOTE
: Not more than 0.8 lb. (13 oz.) of refrigerant be
added to the system at a time to achieve the target sub-
cooling. It is recommended adding 4 oz. refrigerant
each time, then wait 20 minutes to stabilize the system.
4. Disconnect manifold set. Installation is complete.
S-110 CHECKING EXPANSION VALVE OPERATION
1. Remove the remote bulb of the expansion valve from
the suction line.
2. Start the system and cool the bulb in a container of ice
water, closing the valve. As you cool the bulb, the suction
pressure should fall and the suction temperature will rise.
3. Next warm the bulb in your hand. As you warm the bulb,
the suction pressure should rise and the suction tem-
perature will fall.
4. If a temperature or pressure change is noticed, the ex-
pansion valve is operating. If no change is noticed, the
valve is restricted, the power element is faulty, or the
equalizer tube is plugged.
5. Capture the charge, replace the valve and drier, evacu-
ate and recharge.
S-114 NON-CONDENSABLES
If non-condensables are suspected, shut down the system
and allow the pressures to equalize. Wait at least 15 min-
utes. Compare the pressure to the temperature of the cold-
est coil since this is where most of the refrigerant will be. If
the pressure indicates a higher temperature than that of the
coil temperature, noncondensables 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.
S-115 COMPRESSOR BURNOUT
When a compressor burns out, high temperature develops
causing the refrigerant, oil and motor insulation to decom-
pose 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 re-
move 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.
