Air Conditioning Repair Air Conditioning Repair Preventive Maintenance and System Efficiency

Question 1

How often should air conditioning system air filters typically be inspected or replaced in a residential application?

Accepted Answer

Every 1–3 months depending on usage and filter type

Answer

Once every 2 years

Answer

Only when the system stops cooling

Answer

At the time of installation only

Question 2

What is the recommended minimum coil cleaning frequency for a residential split-system AC under normal operating conditions?

Accepted Answer

Once per year

Answer

Every 5 years

Answer

Every 10 years

Answer

Only when ice forms on the coil

Question 3

Which tool is used to measure refrigerant system pressures during a preventive maintenance check?

Accepted Answer

Manifold gauge set

Answer

Megohmmeter

Answer

Anemometer

Answer

Psychrometer

Question 4

What does a high delta-T (temperature difference) across the evaporator coil typically indicate?

Accepted Answer

Good system performance with proper heat absorption

Answer

Low refrigerant charge

Answer

Dirty condenser coil

Answer

Overcharged refrigerant

Question 5

During a preventive maintenance visit, a technician finds the condenser fins are bent and partially blocking airflow. What is the correct action?

Accepted Answer

Straighten the fins using a fin comb

Answer

Replace the entire condenser unit

Answer

Add refrigerant to compensate for reduced efficiency

Answer

Increase the thermostat set point

Question 6

What is the purpose of checking and tightening electrical connections during preventive maintenance?

Accepted Answer

To prevent resistance heating, arcing, and component failure

Answer

To increase system airflow

Answer

To reduce refrigerant charge requirements

Answer

To lower the superheat setting