HVAC: EPA 608 Certification Practice Questions
With Correct Answers
What is temperature glide and what type of blend won't have it?☑️Correct Ans-Temp. blend is
the difference between the dew point and the bubble point
Dew Point☑️Correct Ans-Occurs when saturation temp in evaporator causes refrigerant to
change from liquid to vapor
Bubble Point☑️Correct Ans-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 Ans-No
because different refrigerants in blend have different vapor pressures, causing them to leak at
uneven rates
Refrigeration Process☑️Correct Ans-transfer of heat from one place to another
Evaporator☑️Correct Ans-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 Ans-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 Ans-Rejects heat from system and changes refrigerant from high-temp,
high-pressure vapor into high-pressure, high-temp liquid
Metering Device☑️Correct Ans-reduces pressure of refrigerant and changes the high-pressure,
high-temp liquid into low pressure, low temp liquid.
, Compound Gauge☑️Correct Ans-Typically blue and measures low pressure (psig) and vacuum
(inHg).
High Pressure Gauge☑️Correct Ans-Red and measures high side (discharge) pressure. 0 to 500
psi
What does a compressor compress?☑️Correct Ans-Vapor
Why will refrigerant migrate to the crankcase in a compressor?☑️Correct Ans-Because of the
vapor pressure difference between refrigerant and oil
What color is the high pressure gauge?☑️Correct Ans-Red
What color is the low pressure gauge?☑️Correct Ans-Blue
What needs to happen if oil has been contaminated by burnout?☑️Correct Ans-Triple evacuate
system, install permanent filter-drier, conduct deep vacuum before recharging
What are three Rs of refrigeration?☑️Correct Ans-Recover, recycle, reclaim
Recover☑️Correct Ans-to remove any refrigerant in any condition from system and store in
external container without necessarily testing or processing in any way
Recycle☑️Correct Ans-To clean refrigerant for immediate reuse by separating oil from
refrigerant and removing moisture and acidity from refrigerant by use of products like filter
driers
Reclaim☑️Correct Ans-To process refrigerant to level of new product specifications as
determines by chemical analysis
With Correct Answers
What is temperature glide and what type of blend won't have it?☑️Correct Ans-Temp. blend is
the difference between the dew point and the bubble point
Dew Point☑️Correct Ans-Occurs when saturation temp in evaporator causes refrigerant to
change from liquid to vapor
Bubble Point☑️Correct Ans-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 Ans-No
because different refrigerants in blend have different vapor pressures, causing them to leak at
uneven rates
Refrigeration Process☑️Correct Ans-transfer of heat from one place to another
Evaporator☑️Correct Ans-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 Ans-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 Ans-Rejects heat from system and changes refrigerant from high-temp,
high-pressure vapor into high-pressure, high-temp liquid
Metering Device☑️Correct Ans-reduces pressure of refrigerant and changes the high-pressure,
high-temp liquid into low pressure, low temp liquid.
, Compound Gauge☑️Correct Ans-Typically blue and measures low pressure (psig) and vacuum
(inHg).
High Pressure Gauge☑️Correct Ans-Red and measures high side (discharge) pressure. 0 to 500
psi
What does a compressor compress?☑️Correct Ans-Vapor
Why will refrigerant migrate to the crankcase in a compressor?☑️Correct Ans-Because of the
vapor pressure difference between refrigerant and oil
What color is the high pressure gauge?☑️Correct Ans-Red
What color is the low pressure gauge?☑️Correct Ans-Blue
What needs to happen if oil has been contaminated by burnout?☑️Correct Ans-Triple evacuate
system, install permanent filter-drier, conduct deep vacuum before recharging
What are three Rs of refrigeration?☑️Correct Ans-Recover, recycle, reclaim
Recover☑️Correct Ans-to remove any refrigerant in any condition from system and store in
external container without necessarily testing or processing in any way
Recycle☑️Correct Ans-To clean refrigerant for immediate reuse by separating oil from
refrigerant and removing moisture and acidity from refrigerant by use of products like filter
driers
Reclaim☑️Correct Ans-To process refrigerant to level of new product specifications as
determines by chemical analysis
