Air-Conditioning System Worksheet

The standard design conditions for air-conditioning systems established by the Air-Conditioning, Heating and Refrigeration Institute (AHRI) are

• 95°F outside, 70°F inside, 40% relative humidity.

• 100°F outside, 75°F inside, 50% relative humidity.

• 90°F outside, 80°F inside, 30% relative humidity.

• 95°F outside, 80°F inside, 50% relative humidity.

The typical temperature relationship between a standard-efficiency air-cooled condenser and the ambient temperature is

• 50°F.

• 40°F.

• 30°F.

• 20°F.

The evaporator will normally operate at a _______°F boiling temperature when the indoor temperature is 75°F with a 50% humidity condition.

• 40

• 50

• 60

• 70

A typical temperature relationship between a high-efficiency condenser and the ambient temperature is

• 10°F.

• 20°F.

• 30°F.

• 40°F.

One way manufacturers gain a higher efficiency is by

• designing the unit to run with a higher head pressure.

• equipping the system with a fixed-bore metering device.

• using a larger condenser surface area.

• using a lower evaporator saturation temperature.

Under high evaporator heat loads, the temperature difference between the condenser and the ambient will be

• much higher.

• much lower.

• about the same.

• unpredictable.

The load on the outdoor coil is influenced by

• the indoor dry-bulb temperature.

• the wet-bulb temperature of the indoor air.

• the outdoor temperature and the evaporator heat load.

• the location of the indoor coil.

The sensible-heat load on the indoor coil is influenced by

• the location of the outdoor coil.

• the outdoor temperature and the evaporator heat load.

• the wet-bulb temperature of the indoor air.

• the indoor dry-bulb temperature.

The latent-heat load on the indoor coil is influenced by

• the outdoor temperature and the evaporator heat load.

• the wet-bulb temperature of the indoor air.

• the indoor dry-bulb temperature.

• the location of the outdoor coil.

When a technician has no literature on the equipment and cannot obtain any, what should be done?

• Reference a temperature/pressure chart for refrigerant information.

• Establish some known condition as a reference point.

• Calculate the system superheat and subcooling.

• Test the refrigerant oil for the presence of acid.