HVAC FINAL

The weight of water vapor in a given amount of air is __________.

• condensation point

• boiling point

• evaporation rate

• absolute humidity

Tech A says air-conditioning systems absorb heat from cab through a condenser and transfer heat to the atmosphere using a heat exchanger call an evaporator. Tech B says a refrigerant gas circulated through the A/C system by a pump, absorbs heat and releases it to the atmosphere. Who is correct ?

• Tech A

• Tech B

• Both

• Neither

Laws of thermodynamics, also call Laws of conservation include ?

• Heat moves from cold to hot

• heat moves from hot to cold

• the transfer of heat without an intervening medium

• heat cannot be created or destroyed

Electronic leak detectors for R-1234yf should meet this standard ______

• J1628

• J2913

• J2297

• J2298

At 85'F the low side pressure reads 58 psi, and the high side reads 170 psi what action if any is needed ?

• Add refrigerant

• Needs service possible blockage

• A/C is operating normal

• Needs service possibly faulty compressor

Which of the following statements about types of cooling systems is correct ?

• a vacuum valve incorporated into the cap allows air or coolant to re-enter the cooling system after engine cools

• the freezing points of Ethylene Glycol and Propylene Glycol are the same

• tap water and anti-freeze is the primary coolant medium to absorb engine heat

• a heat exchanger or radiator transfers heat from water to cool the engine

Refrigerants containing dyes should be added to an A/C system only if its at least ____ percent

• 30

• 40

• 50

• 60

You can identify an R-1234yf container by which color ________ container.

• white with red stripe

• blue

• orange

• white with blue stripe

The recovery process on R-12 or R-134A, the A/C system should continue until stable vacuum is held by the system for ______ minutes

• 5

• 4

• 3

• 2

R-134a refrigerant must be recycled to meet which purity standards ?

• DOT-4BA

• J1991

• J2099

• J2788