Comfort Cooling Troubleshooting

Question 1

The required condenser air flow is approximately

Answer 1

1000CFM per ton

Question 2

A dirty condenser prevents the rejection of heat and causes

Answer 2

High head pressure

Question 3

A condenser fan motor with sleeve bearings should be lubricated

Answer 3

2 times per year

Question 4

Improper blower pulley alignment can cause

Answer 4

Unnecessary wear
Erratic speed
Premature belt failure

Question 5

V-Belt tension should be set to about

Answer 5

1 inch

Question 6

To add refrigerant to a partially charged air conditioning system a technician should read the manifold gauges and then

Answer 6

Compare to a Pressure Temperature Chart

Question 7

Starting up an air conditioning system with the indoor temperature at 85 degrees f and the Rh at 70% would be considered

Answer 7

An excessive load

Question 8

During a complete loss of charge condition with a leak on the systems low side and the systems low pressure cut-out control has opened the technician must consider

Answer 8

Finding and repairing the leak
Contaminant in the system
The compressor will not start until the system is recharged

Question 9

After a system evacuation ___________ can cause a micron gauge to rise from 250 microns to 500 microns before leveling off

Answer 9

Excessive contamination

Question 10

To clean an excessively moisture contaminated system a technician may perform a

Answer 10

Triple evacuation

Question 11

A full or partial restriction of the capillary tube is often the result of

Answer 11

Too much oil charge
Incorrect oil viscosity
Liquid refrigerant entering the compressor crankcase

Question 12

An air conditioning system with a fluctuating evaporator pressure would most likely be the result of a

Answer 12

Defective AEV

Question 13

A system operating with a loose thermal expansion valve sensing element would cause the systems superheat to be

Answer 13

Too low

Question 14

Any evaporator with a pressure drop in excess of _________ should use a thermal expansion valve with an external equalizer

Answer 14

2.5 psig

Question 15

Any system operating with a thermal expansion valve can automatically adjust to a change in the load condition. In order to supply an adequate volume of refrigerant the system must also utilize

Answer 15

A receiver

Question 16

An air conditioning system using a TXV with an undercharge of refrigerant can be identified by

Answer 16

Low suction pressure
Low system capacity
High superheat

Question 17

If an air conditioning compressor is allowed to operate with a low refrigerant charge the compressor is likely

Answer 17

To be very hot

Question 18

An air conditioning system using a TXV and operating with an overcharge of refrigerant can be identified by

Answer 18

High discharge pressure
Higher than normal suction pressure
Low system capacity

Question 19

An overcharged air conditioning system using a capillary tube metering device would

Answer 19

Have high head pressure
Have high suction pressure
Allow liquid refrigerant to enter the compressor

Question 20

A properly charged air conditioning system with a dirty air filter could

Answer 20

Frost back to the compressor