EPA 608 Certification Study Guide HVAC Questions and Answers 100% A+ Graded Excel!!!
11 views 0 purchase
Course
EPA 608 Universal
Institution
EPA 608 Universal
EPA 608 Certification Study Guide HVAC Questions and Answers 100% A+ Graded Excel!!!
Are there drop-in replacements for R-12 systems? Why or why not? - CORRECT ANSWER-No because the new refrigerants are incompatible with the oils and lubricants used in R-12 systems.
What type of oil is used i...
EPA 608 Certification Study Guide
HVAC Questions and Answers 100%
A+ Graded Excel!!!
Are there drop-in replacements for R-12 systems? Why or why not? - CORRECT
ANSWER-No because the new refrigerants are incompatible with the oils and lubricants
used in R-12 systems.
What type of oil is used in R-134a and what oils will it mix with? - CORRECT ANSWER-
Ester based oils and they do not mix with other oils
What type of lubricant is used with HCFCs? - CORRECT ANSWER-Alkylbenzene lubricant
What is difference b/w ternary blend a azeotropic blend? - CORRECT ANSWER-Ternary
blends are three-part mixtures whereas azeotropic blends are blends of two or more
compounds that act like a single compound.
What is the trait of a hygroscopic lubricant? - CORRECT ANSWER-It absorbs (takes on)
moisture
What is temperature glide and what type of blend won't have it? - CORRECT ANSWER-
Temp. blend is the difference between the dew point and the bubble point
Dew Point - CORRECT ANSWER-Occurs when saturation temp in evaporator causes
refrigerant to change from liquid to vapor
Bubble Point - CORRECT ANSWER-Occurs when saturation temp in condenser changes
refrigerant from vapor to liquid
Will the gases in a ternary blend leak at the same rate? Why or why not? - CORRECT
ANSWER-No because different refrigerants in blend have different vapor pressures,
causing them to leak at uneven rates
Refrigeration Process - CORRECT ANSWER-transfer of heat from one place to another
, Evaporator - CORRECT ANSWER-Absorbs heat into system from space to be cooled.
Absorption of heat causes refrigerant to boil. Upon leaving, refrigerant changed to low
pressure, low temperature vapor
Compressor - CORRECT ANSWER-Takes low pressure, low temp vapor and changes it
to a high-temp, high-pressure, superheated vapor and delivers it to the condenser
Condenser - CORRECT ANSWER-Rejects heat from system and changes refrigerant from
high-temp, high-pressure vapor into high-pressure, high-temp liquid
Metering Device - CORRECT ANSWER-reduces pressure of refrigerant and changes the
high-pressure, high-temp liquid into low pressure, low temp liquid.
Compound Gauge - CORRECT ANSWER-Typically blue and measures low pressure (psig)
and vacuum (inHg).
High Pressure Gauge - CORRECT ANSWER-Red and measures high side (discharge)
pressure. 0 to 500 psi
What does a compressor compress? - CORRECT ANSWER-Vapor
Why will refrigerant migrate to the crankcase in a compressor? - CORRECT ANSWER-
Because of the vapor pressure difference between refrigerant and oil
What color is the high pressure gauge? - CORRECT ANSWER-Red
What color is the low pressure gauge? - CORRECT ANSWER-Blue
What needs to happen if oil has been contaminated by burnout? - CORRECT ANSWER-
Triple evacuate system, install permanent filter-drier, conduct deep vacuum before
recharging
What are three Rs of refrigeration? - CORRECT ANSWER-Recover, recycle, reclaim
Recover - CORRECT ANSWER-to remove any refrigerant in any condition from system
and store in external container without necessarily testing or processing in any way
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller ShowvinePublishers. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $10.84. You're not tied to anything after your purchase.
