SERVICING
16
2.
Start the vacuum pump and open the shut off valve to
the high vacuum gauge manifold only. After the com-
pound gauge (low side) has dropped to approximately
29 inches of vacuum, open the valve to the vacuum
micron gauge. See that the vacuum pump will blank-off
to a maximum of 500 microns. A vacuum pump can only
produce a good vacuum if its oil is non-contaminated.
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
EVACUATION
3. If the vacuum pump is working properly, close the
valve to the micron 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 micron gauge.
5. Continue to evacuate to a maximum of 500 microns.
Close valve to vacuum pump and watch rate of rise.
If vacuum does not rise above 500 microns in three
to five minutes, system can be considered properly
evacuated.
6.
If micron gauge continues to rise and levels off at
about 2000 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 micron gauge and vacuum pump.
Shut off pump and prepare to charge.
CHARGING
WARNING
REFRIGERANT UNDER PRESSURE!
•
Do not overcharge system with refrigerant.
•
Do not operate unit in a vacuum or at negative pressure.
Failure to follow proper procedures may cause property
damage, personal injury or death.
CAUTION
Use refrigerant certified to AHRI standards. Used
refrigerant may cause compressor damage and is not covered
by the warranty. Most portable machines cannot clean used
refrigerant to meet AHRI Standards.
CAUTION
Damage to the unit caused by operating the compressor with
the suction valve closed is not covered under the warranty
and may cause serious compressor damage.
Charge the system with the exact amount of refrigerant.
See the Installation Manual for the correct refrigerant
charge.
An inaccurately charged system will cause future problems.
1. When using an ambient compensated calibrated
charging cylinder, allow liquid refrigerant only to enter
the high side.
2. Once the system stops taking refrigerant, close the
valve on the high side of the charging manifold.
3. Start the system and charge the balance of the refrig-
erant through the low side.
NOTE:
R410A should be drawn out of the storage container
or drum in liquid form due to its fractionation properties, but
should be “Flashed” to its gas state before entering the sys-
tem. There are commercially available restriction devices
that fit into the system charging hose set to accomplish this.
DO NOT
charge liquid R410A into the compressor.
4. With the system still running, close the valve on the
charging cylinder. At this time, you may still have
some liquid refrigerant in the charging cylinder hose
and will definitely have liquid in the liquid hose.
Reseat the liquid line core. Slowly open the high side
manifold valve and transfer the liquid refrigerant from
the liquid line hose and charging cylinder hose into
the suction service valve port. CAREFUL: Watch so
that liquid refrigerant does not enter the compressor.
