HVAC Air Conditioning 3

Question 1

What condition is indicated when a technician measures frost forming uniformly across the entire evaporator coil surface?

Accepted Answer

Low airflow across the coil

Answer

Normal operation

Answer

Overcharge of refrigerant

Answer

TXV stuck open

Question 2

Which refrigerant replaced R-22 as the standard for residential air conditioning in the United States?

Accepted Answer

R-410A

Answer

R-134a

Answer

R-407C

Answer

R-32

Question 3

What is the function of a crankcase heater on a compressor?

Accepted Answer

Prevent refrigerant migration and dilution of oil during the off cycle

Answer

Preheat suction gas before compression

Answer

Increase compression ratio

Answer

Protect motor windings from overvoltage

Question 4

A technician measures a temperature split of 14°F across the evaporator (return air 75°F, supply air 61°F). What does this suggest?

Accepted Answer

Normal operation for a properly sized system

Answer

System is significantly underperforming

Answer

Refrigerant overcharge

Answer

Condenser is fouled

Question 5

What is the purpose of the filter-drier in an air conditioning system?

Accepted Answer

Remove moisture and contaminants from the refrigerant

Answer

Reduce refrigerant pressure

Answer

Separate oil from refrigerant

Answer

Meter refrigerant flow to the evaporator

Question 6

Which EPA section governs the handling and recovery of refrigerants?

Accepted Answer

Section 608

Answer

Section 404

Answer

Section 609

Answer

Section 612

Question 7

What does the term 'ton of refrigeration' refer to?

Accepted Answer

12,000 BTU/hr of cooling capacity

Answer

The weight of the condensing unit

Answer

The refrigerant charge weight in the system

Answer

1 ton = 1,000 watts of electrical consumption