Goodman Mfg R-410A - Manual (Page 35)

SERVICING
35
Moisture chemically reacts with the refrigerant and oil to form
corrosive hydrofluoric and hydrochloric acids. These attack
motor windings and parts, causing breakdown.
The equipment required to thoroughly evacuate the system is
a high vacuum pump, capable of producing a vacuum equiva-
lent to 25 microns absolute and a thermocouple vacuum gauge
to give a true reading of the vacuum in the system
NOTE: Never use the system compressor as a vacuum pump
or run when under a high vacuum. Motor damage could occur.
WARNING
SCROLL COMPRESSORS
DO NOT FRONT SEAT THE SERVICE VALVE(S) WITH
THE COMPRESSOR OPERATING IN AN ATTEMPT TO
SAVE REFRIGERANT. WITH THE SUCTION LINE OF
THE COMPRESSOR CLOSED OR SEVERLY RESTRICT-
ED, THE SCROLL COMPRESSOR WILL DRAW A DEEP
VACUUM VERY QUICKLY. THIS VACUUM CAN CAUSE
INTERNAL ARCING OF THE FUSITE RESULTING IN A
DAMAGED OR FAILED COMPRESSOR.
1. Connect the vacuum pump, vacuum tight manifold set with
high vacuum hoses, thermocouple vacuum gauge and charg-
ing cylinder as shown.
LOW SIDE
GAUGE
AND VALVE
HIGH SIDE
GAUGE
AND VALVE
TO
UNIT SERVICE
VALVE PORTS
VACUUM PUMP
VACUUM PUMP
ADAPTER
800 PSI
RATED
HOSES
CHARGING
CYLINDER
AND SCALE
2. Start the vacuum pump and open the shut off valve to the
high vacuum gauge manifold only. After the compound
gauge (low side) has dropped to approximately 29 inches
of vacuum, open the valve to the vacuum thermocouple
gauge. See that the vacuum pump will blank-off to a maxi-
mum of 25 microns. A high vacuum pump can only pro-
duce a good vacuum if its oil is non-contaminated.
3. If the vacuum pump is working properly, close the valve to
the vacuum thermocouple gauge and open the high and
low side valves to the high vacuum manifold set. With the
valve on the charging cylinder closed, open the manifold
valve to the cylinder.
4. Evacuate the system to at least 29 inches gauge before
opening valve to thermocouple vacuum gauge.
5. Continue to evacuate to a minimum of 250 microns. Close
valve to vacuum pump and watch rate of rise. If vacuum
does not rise above 1500 microns in three to five minutes,
system can be considered properly evacuated.
6. If thermocouple vacuum gauge continues to rise and levels
off at about 5000 microns, moisture and non-condensables
are still present. If gauge continues to rise a leak is present.
Repair and re-evacuate.
7. Close valve to thermocouple vacuum gauge and vacuum
pump. Shut off pump and prepare to charge.
S-103 CHARGING
WARNING
USE REFRIGERANT CERTIFIED TO ARI STANDARDS.
USED REFRIGERANT MAY CAUSE COMPRESSOR
DAMAGE AND WILL VOID THE WARRANTY. MOST
PORTABLE MACHINES CANNOT CLEAN USED
REFRIGERANT TO MEET ARI STANDARDS.
CAUTION
OPERATING THE COMPRESSOR WITH THE SUCTION
VALVE CLOSED WILL VOID THE WARRANTY AND
CAUSE SERIOUS COMPRESSOR DAMAGE.
CAUTION
Charge the system with the exact amount of refrigerant.
Refer to the specification section or check the unit nameplates
for the correct refrigerant charge.
An inaccurately charged system will cause future prob-
lems.
1. Using a calibrated set of refrigerant scales, allow liquid re-
frigerant only to enter the high side.
2. After the system will take all it will take, close the valve on
the high side of the charging manifold.
3. Start the system and charge the balance of the refrigerant
through the low side.