Robinair 34988 Recovery, Recycling, Recharging Unit - Manual (Page 13)

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554228 Rev. E July 30, 2013
Evacuate the A/C System
1. Ensure service hoses are connected to the
vehicle A/C system, and coupler valves are
OPEN.
2. Select VACUUM.
3. The unit gives you the option of doing a leak
test after evacuation. Select TOGGLE LEAK to
turn the leak test OFF / ON.
4. Select START to accept the default evacuation
time, or enter the desired vacuum time using the
number keys, and select START.
IMPORTANT: The unit pulls a vacuum on the
vehicle A/C system to remove air and boil off
moisture that may be present in the system .
Evacuate the system for at least 10 minutes,
or follow the A/C system manufacturer’s
specifications, to ensure adequate moisture
and contaminant removal .
5. The unit evacuates the A/C system and stops
when the specified amount of time has elapsed.
Select EXIT to continue.
Note: During the vacuum process, the unit may
perform a tank fill or an air purge, if needed.
You are now ready to either manually replenish
the A/C system with new oil or to recharge the
system with refrigerant.
Operating Tips
• If the vacuum pump has run for 10 or
more hours without an oil change, the
unit displays
MAINTAIN VACUUM PUMP
VACUUM OIL TIME XX:XX
OIL LIFE REMAINING XX:XX
CHANGE VACUUM PUMP OIL NOW?
SELECT YES TO CHANGE OIL
OR NO TO EXIT.
Refer to instructions in the Maintenance
section under Change Vacuum Pump Oil.
• Before the unit begins evacuating the A/C
system, it checks for any pressure in the
system that might damage the vacuum
pump. If pressure is detected, the unit
displays
PRESSURE TOO HIGH FOR VACUUM!
PRESS EXIT
Select EXIT, and recover refrigerant
before proceeding.
• If a leak test was programmed and a leak
is detected, the unit displays
LEAK TEST FAILED
PRESS YES TO CONTINUE
NO TO ABORT
Select NO to exit the evacuation,
perform needed repairs, and repeat the
evacuation.
• To ensure an accurate leak test, it is
imperative that a thorough recovery and
evacuation of the system be performed.
During the recovery process, cold spots
can develop in the A/C system. Pockets
of refrigerant in desiccant and in system
oil will continue to vaporize as the A/C
system temperature equalizes toward
ambient. As this occurs, A/C system
pressure will increase, which may be
interpreted by the unit as a leak.
This will vary somewhat with ambient
temperature conditions.
Operating Instructions