1. Before charging a new system with refrigerant, what should be done?
- ✔️ Pressurize with nitrogen (classified as an inert gas) and leak test.
2. Which refrigerant can be used for leak detection as a trace gas and pressurized with nitrogen?
- ✔️ R-22.
3. What tools can be used to find the general area of leaks and pinpoint them?
- ✔️ Electronic or ultrasonic leak detector will provide the general area of the leak.
_(Other options include soap bubbles, looking for oil residue, and refrigerant dye which are useful as
well.)_
### Leak Indicators and Visual Inspection
4. Traces of oil around a sight glass inlet fitting of a refrigeration system might indicate:
- ✔️ A leak.
5. Ways you can visually look for leaks include:
- ✔️ All the above (using soap bubbles, looking for traces of oil, excessive superheat caused by low
refrigerant charge).
### Equipment Classifications
6. Type II classification, as identified by the EPA, applies to what equipment?
- ✔️ Split air conditioning equipment with five (5) pounds of refrigerant or more.
### Leak Repair Requirements
, 7. What are the leak repair requirements for comfort cooling appliances and commercial appliances
containing 50 lbs. or more of refrigerant?
- ✔️ c. a and b: Must be repaired if leak rate exceeds 15% in comfort cooling appliances and 35% in all
commercial and industrial process refrigeration.
### Common Refrigerants
8. What type of refrigerant was the most common before outlawing CFCs and HCFCs?
- ✔️ R-22.
### Evacuation Standards
9. The required level of evacuation for recovery equipment manufactured after November 15, 1993, on
a system containing less than 200 pounds of R-12 refrigerant is:
- ✔️ 10 inches Hg.
What is the purpose of the filter drier and when should it be changed?
a. To filter the oil. Change every year.
b. To remove moisture from the refrigerant, replace on a routine basis
or anytime a system is opened
c. Cleans the air. Replace monthly
d. Dryer's air filters. Replace yearly ✔️b. To remove moisture from the refrigerant, replace on a routine
basis or anytime a system is opened
Industrial process and commercial refrigeration equipment with over 50 pounds
of refrigerant with an annual leak rate of ___ % requires repair under EPA
regulations.
a. 0
b. 15
c. 35