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SERVICING
The equipment required to thoroughly evacuate the system is
a high vacuum pump, capable of producing a vacuum equiv-
alent 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
Do not front seat the service valve(s) with the
compressor open, with the suction line of the
comprssor closed or severely restricted.
1. Connect the vacuum pump, vacuum tight manifold set
with high vacuum hoses, thermocouple vacuum gauge
and charging cylinder as shown.
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
maximum of 25 microns. A high vacuum pump can only
produce a good vacuum if its oil is non-contaminated.
LOW SIDE
GAUGE
AND VALVE
EVACUATION
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 maximum 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.
44
HIGH SIDE
GAUGE
AND VALVE
6. If thermocouple vacuum gauge continues to rise and
levels off at about 5000 microns, moisture and non-con-
densables 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
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.
Only use refrigerant certified to AHRI standards. Used
refrigerant may cause compressor damage. The
manufacturer is not responsible for damage or the
need for repairs resulting from the use of unapproved
refrigerant types or used or recycled refrigerant. Most
portable machines cannot clean used refrigerant to
meet AHRI standards.
Charge the system with the exact amount of refrigerant.
Refer to the specification section or check the unit name-
plates for the correct refrigerant charge.
An inaccurately charged system will cause future
problems.
1. Using a quality set of charging scales, weigh the proper
amount of refrigerant for the system. Allow liquid refrig-
erant 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.
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
system. 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.
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