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Installation and Operation
The
1090AT diagnostic™ unit will
remove refrigerant from the vehicle
system until it reaches a vacuum of
6 inHg at which time it will enter a 2
minute hold mode.
If at any time during the 2 minute hold
the pressure rises to 3 PSI, the recovery
process will automatically restart and
once again pull the vehicle’s A/C system
down to 6 inHg.
The
1090AT diagnostic™ will continue
this process as long as there is
refrigerant left in the system. Depending
upon ambient conditions and the
temperature of the refrigerant, this cycle
could continue a number of times.
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DO NOT shut the unit OFF during
this process.
5. When recovery is complete, the
1090AT
diagnostic™ will do an oil purge, and if
necessary, will purge non-condensables
(air).
6. The display will indicate a completed
recovery and show the amount of
refrigerant recovered.
7. Record the amount of oil recovered with
the refrigerant. The amount indicated is
the amount to add back into the vehicle
A/C system when recharging.
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Discard refrigerant oil in
accordance with local, state and
federal regulations that apply in
your area.
8. Press the N button to return to the main
menu screen.
9. Close the blue and red service hose
couplers before removing service hoses
from the vehicle.
Purging Non-condensable
Gas
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Purging non-condensable gases is
an automatic feature executed by
the
1090AT diagnostic™ unit.
Evacuating A/C System
Use this procedure to remove non-
condensable gases and moisture from the
vehicle A/C system.
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Always check the oil level of the
vacuum pump before operation.
The oil level should be half way up
the sight glass. If no oil level is
shown, fill the vacuum pump with
oil. Run the vacuum pump for
several seconds and turn OFF
before checking oil level.
1. Open the liquid and vapor recovery tank
valves.
2. Power up the
1090AT diagnostic™ unit.
3. Connect the service hoses to the vehicle
and open service hose couplers. For
additional information refer to
Connecting
Service Hoses to Vehicle.
4. Select VACUUM and press ENTER.
5. Use the UP/DOWN arrow buttons to
adjust time to desired value.
6. Select START and press ENTER to start
the evacuation.
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If pressure exists in the vehicle A/C
system, recover the system before
starting the vacuum pump.
The panel gauges show vacuum
increasing.
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Follow the manufacturer
recommendations for evacuation
time, usually at least 30 minutes.
For Reference Only
