Barko 830B, Руководство по обслуживанию

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26-6
®
SERVICE- HVAC SYSTEM
(continued...)
1) Insure all fittings are tight and components
installed correctly. Use mineral oil on o-rings and
fitting threads.
2) Attach manifold gauge set to high and low side
service ports. The blue coupler attaches to low
pressure charge port and red coupler attaches to
high pressure charge port. Attach center hose to
nitrogen bottle with regulator and introduce 150 psi
into system. Observe gauge for 10 min. to check for
leaks, release nitrogen from system and proceed to
#3.
3) Attach yellow (center) hose from manifold gauge
set to vacuum pump.
4) Attach Thermistor Vacuum Gauge to a/c system
not at the vacuum pump. The reading at the vacuum
pump may not give an accurate indication of the true
vacuum in the a/c system.
5) Start vacuum pump.
6) Open both red and blue (high and low side)
valves on manifold gauge set.
7) Let vacuum pump run until thermistor vacuum
gauge reads 1000 microns. Then run an additional
15 minutes.
8) Close red and blue valves on manifold gauge set.
9) Monitor pressure reading on thermistor vacuum
gauge for 10 minutes with vacuum pump off and
manifold gauge valves closed. Reading should be
between 1000 and 400 microns and should not climb
above 1000 microns.
10) If pressure in a/c system rises above 1000
microns the system has a leak and needs to be
repaired prior to charging system.
11) After verifying the system has no leaks,
remove thermistor vacuum gauge. Vacuum gage
may be damage if pressurized above atmospheric
pressure.
12) Attach yellow hose from manifold gauge set to
refrigerant.
13) Place refrigerant tank upside down on charging
scale. (Yellow hose should be attached and tank
valve open.)
1.2.3 A/C Charging Procedure (refer to figures and table on next page for more information)
14) Zero charging scale measurement.
15) Open red (high side) valve on manifold gauge
set and add the factory recommended charge
amount. Close red valve on manifold gage set.
Charging is complete. Verify proper a/c operation.
Document total refrigerant added to system and
apply appropriate label near compressor stating
refrigerant charge amount.
16) If the proper refrigerant charge amount is not
known, add one to two pounds of liquid refrigerant to
the system through the high side port (red). The
amount of refrigerant added depends on the
estimated full charge amount. It is typically ½ to ¾ of
the estimated full charge. Close red valve on
manifold gauge set. This type of refrigerant
charging should be done at an ambient temperature
of 32°C (90°F) or greater with machine doors open
to provide a load on the evaporator.
17) Turn refrigerant tank right side up on charging
scale (vapor charge position).
18) Start machine engine and turn on a/c system.
19) Record ambient temperature, evaporator inlet
temperature, evaporator air outlet temperature,
suction pressure and discharge pressure.
20) If suction pressure is 5 psig or less, keep engine
speed at idle until additional refrigerant has been
added and suction pressure exceeds 5 psig. Then
increase engine RPM to 1/2 throttle.
21) Slowly open blue valve on manifold gauge set
and bleed vapor refrigerant into low side of system in
small increments (0.1 to 0.2 lbs at a time). Suction
pressure should not exceed 50 psig while charging
vapor into the low side of the system or the
compressor can be damaged.
22) Continue to add refrigerant in this manner in
small increments until optimum a/c performance is
achieved. Highest temp differential between
evaporator inlet and outlet air temps. Check that
Head Pressure is in specs. [ See Temperature
Pressure Chart ]
23) Document total amount or refrigerant added to
system and apply appropriate label near compressor
stating refrigerant charge amount.
05/31/2019
Updated
SERVICE