8
VACUUM cont.
Note:
If the automobile A/C system has pressure on it,
the unit will automatically begin a recovery cycle to in-
sure that no refrigerant is released into the atmosphere.
10. The 37880 SERIES will begin to evacuate the A/C
system and will beep to indicate the end of the vac-
uum time.
11. Record the vacuum level shown on the LCD and
press START to begin the vacuum hold time. The
hold time will count down on the LCD and the unit
will beep at the end of the hold time.
12. Record the final vacuum level shown on the LCD If
the two recorded vacuum levels are different, the
A/C system may have a leak and might not retain
refrigerant when charged.
13. The unit will prompt you to
“INJECT OIL NOW”
press and hold the START key until the desired
amount of oil is injected into the A/C system.
14. Verify the message on the LCD reads
“VACUUM
COMPLETE.”
15. Press the RESET key to return to the main menu.
16. Shut the service valves and disconnect the high and
low side auto service hoses from the automobile.
Model 37889 with integrated micron gauge (Only) -
See page 9 for instructions that will outline how to use
this feature.
CHARGE
The Charge Only function is designed to add a precise
amount of refrigerant when the A/C system is low on
refrigerant. This mode is most often used when the A/C
system is working but does not produce sufficiently cold
air.
Note: THE A/C SYSTEM MUST BE IN A VACUUM
BEFORE THE CHARGING PROCESS.
MODE 3 Operational Steps
:
NOTE: If desired, the gauges of the 37880 can now
be used to aid investigation of an A/C system prob-
lem. Ensure the automobile A/C system is turned
off prior to selecting a mode on the 37880.
1. Verify the auto air conditioning system is off.
2. Select CHARGE option from the main menu.
3. When the LCD reads
“SET CHARGE AMOUNT,”
set the amount of refrigerant to be charged into the
A/C system by using the numeric keypad until the
desired amount is shown. press ENTER to set the
charge amount on the LCD.
NOTE:
To change
units from pounds and ounces, ounces or kilograms
press the START key. The unit will then ask you to
confirm the charge amount. Press the ENTER key
to confirm.
4. The LCD will read “
CONNECT SERVICE HOSES
TO THE VEHICLE ENTER TO CONTINUE”
. Press
the
ENTER
key.
5. Connect the high and low side auto service hoses
to the respective high and low side service ports on
the automobile A/C system. Open the service hose
valves.
6. The LCD should read
“PUSH START.”
7. Press START key to begin charging operations.
The display will read “STABILIZING PLEASE WAIT”
The 37880 Series will then start the charge cycle.
The LCD will display the charging process progress.
The unit will beep when the desired charge amount has
been transferred to the A/C system.
Note: The last 3 oz. of refrigerant charge will be me-
tered in by the charging solenoid. It is normal to hear a
clicking sound while charging.
8. Verify the message on the LCD reads
“CHARGE
COMPLETE.”
Press the RESET key and the
Unit
will force a hose clearing routine. Close the service
valves and disconnect the high and low side auto
service hoses from the auto.
9. Press the ENTER key to return to the main menu
Low Side Charge
The system default setting is high-side charging. To
charge low-side, follow these steps:
1. Turn the unit off.
2. Press and hold number 3 key down on the nu-
meric key keypad and turn the unit on.
3. When the display reads “low side charge,” release
the charge key.
4. Enter the charge amount.
Note: when the unit is turned off it will default back to
high-side charge.
