Operation CHARM: Car repair manuals for everyone.

Evacuate System Using Charging Station


A vacuum pump is built into the charging station and is constructed to withstand repeated and prolonged use without damage. Complete moisture removal from the system is possible only with a vacuum pump constructed for the purpose.
The system must be completely discharged before it can be evacuated. Damage to the vacuum pump may result if pressurized refrigerant is allowed to enter.
1. Connect hose to vacuum pump, if system was discharged through charging station.
2. Open low side gauge hand valve of charging station.
3. Connect station into 110 volt current.
4. Turn vacuum pump on according to instructions for specific station being used.
5. Evacuate system with the vacuum pump until the low pressure gauge reads at least 28 inches of vacuum. Continue evacuating system for an additional 15 minutes for routine system servicing or 20 to 30 minutes, if any parts have been replaced.
6. Close low side gauge hand valve, then turn vacuum pump "OFF."
7. Check ability of system to hold vacuum. Watch low side gauge to see that gauge does not rise at a faster rate than 1 inch vacuum every 4 to 5 minutes. If low side gauge rises at too rapid a rate, install partial charge and leak test. Then evacuate system again.
8. If system holds vacuum, charge system with refrigerant.