EPA 608 609 System Evacuation and Charging Procedures

Question 1

What is the primary purpose of evacuating a refrigeration system before charging with refrigerant?

Accepted Answer

To remove moisture and non-condensable gases

Answer

To pre-cool the system

Answer

To test for refrigerant leaks

Answer

To purge the remaining old refrigerant

Question 2

What instrument is used to measure the depth of vacuum during system evacuation?

Accepted Answer

Micron gauge (electronic vacuum gauge)

Answer

Manifold gauge set

Answer

Thermometer

Answer

Refrigerant identifier

Question 3

What vacuum level in microns must be achieved before charging most residential HVAC systems per industry standards?

Accepted Answer

500 microns

Answer

1,000 microns

Answer

2,000 microns

Answer

5,000 microns

Question 4

What should a technician investigate if the vacuum rises rapidly above 1,000 microns immediately after isolating the vacuum pump?

Accepted Answer

A system leak or residual moisture

Answer

Begin charging immediately since the pump is done

Answer

Add more compressor oil to the system

Answer

Run the vacuum pump for an additional hour

Question 5

Why should a technician evacuate from both the high and low sides of a refrigeration system?

Accepted Answer

To achieve faster and more thorough evacuation past any closed internal valves

Answer

To increase system operating pressure

Answer

Because DOT requires dual-port evacuation

Answer

To measure superheat from both sides simultaneously

Question 6

What type of oil must be used in vacuum pumps designed for HVAC/R refrigerant work?

Accepted Answer

Dedicated vacuum pump oil

Answer

SAE 30 motor oil

Answer

Standard mineral oil

Answer

Synthetic compressor oil