- Follow the entire path of the refrigerant system.
- Completely circle each joint at 1-2 inches (25-50 mm) per second.
- Hold the probe tip within 1/4 inch (6 mm) of the surface.
- Do not block the air intake.
- The audible tone changes from 1-2 clicks per second into a solid alarm if there is a leak. Adjust the balance control to maintain 1-2 clicks per second.
Test all of the following areas, even after one leak has been confirmed:
Evaporator inlet and outlet.
The sealing caps provide protection for the service ports. Make sure that these caps are not missing or loose. Always use the correct cap for each port.
Leaks in the evaporator core are difficult to find. Test the evaporator core using the following procedure:
- Run the blower fan at the maximum speed setting for at least 15 minutes.
- Turn the blower OFF.
- Wait for 10 minutes.
- Remove the blower motor resistor.
- Insert the leak detector probe as close as possible to the evaporator core. The detector will indicate a leak with a solid alarm.
- Use a flashlight to search for refrigerant oil on the core surface.