Service Instructions
SERVICING
113
Do not front seat the service valve(s) with the
Compressor open, with the suction line of the
comprssor closed or severely restricted
.
WARNING
IMPORTANT NOTE: Because of the potential damage to compres-
sors, do not allow suction pressure at service valve to drop below
20 PSIG when pumping unit system down for repair. Outdoor
section, depending on line set length and amount of charge in
system, may not be able to hold the entire system charge.
This is the most important part of the entire service procedure.
The life and efficiency of the equipment is dependent upon the
thoroughness exercised by the serviceman when evacuating air
(non-condensables) and moisture from the system. Air in a
system causes high condensing temperature and pressure, re-
sulting in increased power input and reduced performance.
Moisture chemically reacts with the refrigerant oil to form
corrosive acids. These acids attack motor windings and parts,
causing breakdown. The equipment required to thoroughly evacu-
ate the system is a high vacuum pump, capable of producing a
vacuum equivalent to 250 microns or less and a vacuum gauge
to give a true reading of the vacuum in the system.
NOTE: Never use the Scroll compressor as a vacuum pump or run
when under a high vacuum. Motor damage could occur.
Condensing unit liquid and suction valves are closed to contain
the charge within the unit. The unit is shipped with the valve stems
closed and caps installed. Do not open valves until the system
is evacuated.
1. Connect the vacuum pump with 250 micron capability to the
service valves.
2. Evacuate the system to 250 microns or less using suction and
liquid service valves. Using both valves is necessary as some
compressors create a mechanical seal separating the sides
of the system.
3. Close pump valve and hold vacuum for 10 minutes. Typically
pressure will rise during this period.
4. If the pressure rises to 1000 microns or less and remains
steady the system is considered leak free; proceed to startup.
5. If pressure rises above 1000 microns but holds steady below
2000 microns, moisture and/or non-condensibles may be
present or the system may have a small leak.
6. Return to step 2: If the same result is encountered check for
leaks as previously indicated and repair as necessary then
repeat evacuation.
7. If pressure rises above 2000 microns, a leak is present. Check
for leaks as previously indicated and repair as necessary
then repeat evacuation.
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
S-103 CHARGING
* 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.
WARNING
REFRIGERANT UNDER PRESSURE!
CAUTION
Use refrigerant certified to AHRI standards. Used
refrigerant may cause compressor damage and is
not covered under the warranty. Most portable
machines cannot clean used refrigerant to meet
AHRI standards.
CAUTION
with the suction valve closed is not covered under the
Damage to the unit caused by operating the compressor
warranty and may cause serious compressor damage.