Function and feature System Quiz

What is the SI Base unit for temperature?

• Celsius

• Rankine

• Kelvin

• Fahrenheit

A RACHP liquid line contains liquid at a temperature of 35oC, if the ambient temperature surrounding the liquid line is 25oC, which thermodynamic law applies to the resulting heat transfer.

• First Law.

• Second Law.

• Charles’ Law.

• Boyle’s Law.

What is the definition of latent heat?

• Heat that changes the temperature of a substance during a change of state from solid.

• Heat that changes both the state and temperature of a substance simultaneously.

• Heat that changes the state of a substance without changing its temperature.

• Heat that changes the temperature of a substance without changing its state.

Which formula is used to calculate pressure?

• P = M x A

• P = F/A

• P = M x G

• P=F x M x A

What condition would the refrigerant in the evaporator coil be in on a running RACHP system?

• Subcooled two phase mixture.

• Saturated two phase mixture.

• Subcooled vapour.

• Superheated liquid.

Where would the compressor discharge temperature be found on a Pressure Enthalpy chart?

• Liquid area.

• Saturated two phase area.

• Superheated area.

• Subcooled area.

What information is provided by a sling psychrometer?

• Moisture content and wet bulb temperature.

• Dry bulb and humidity pressures.

• Dry bulb and wet bulb temperatures.

• Humidity and moisture content.

What material is an alloy?

• Copper.

• Brass.

• Iron.

• Zinc.

What expansion device will allow refrigerant to flow in either direction?

• Low side float valve.

• Internally equalised T.E.V.

• Short tube restrictor.

• Externally equalised T.E.V.

A RACHP engineer has to select the correct pipe sizes for a RACHP system. What characteristic should the suction line have?

• Small enough to minimise pressure drop.

• Large enough to minimise pressure drop.

• Achieve the lowest possible velocity to achieve greatest oil return.

• Free of any P Traps which would prevent oil return.