ACR108 - Unit 14 - Automatic Controls (CRF) - Mr. Graham

The purpose of a heat anticipator is to ____.

• anticipate a sudden rise in temperature

• keep the thermostat warm

• reduce the temperature swing of a conditioned space

• ensure that the system transformer does not overheat

The difference between system overshoot and system lag is called ____.

• room temperature

• temperature rise

• temperature swing

• room swing

What is meant by the term "detent"?

• Slow motion of a contact to ensure good electrical contact.

• Rapid making and breaking of a contact.

• The compensation furnished by heaters in the thermostat.

• The control of the blower in the air handler.

The heat anticipator in the thermostat control circuit in the heating mode is active when the ____.

• heating contact is open

• heating contact is closed

• fan switch is open

• fan switch is closed

The heater in the thermostat control circuit in the cooling mode is active when the ____.

• cooling contact is open

• cooling contact is closed

• fan switch is open

• fan switch is closed

The cold anticipator is wired in ____ with the mercury bulb cooling contacts and is energized during the off cycle.

• parallel

• series

• sequence

• opposition

To properly set the heat anticipator, the ____ must determine what the current flow is through the heating control circuit when the furnace is operating in a steady state condition.

• manufacturer

• homeowner

• electrician

• heating technician

Line voltage thermostats have heavier contacts and use which type of sensing element?

• bimetal

• bellows

• remote bulb

• All of the Above

To obtain an accurate reading of a fluid in a large pipe, a technician should ____.

• strap a dial-type pocket thermometer to the pipe

• use a digital thermometer in a glass of ice water

• use a permanently mounted thermometer in a well

• Any of the above will work fine.

A low pressure control has a "high event" and a "differential" setting. The technician wants the system to turn on at 28 psig and shut down at 2 psig. What would be the proper settings?

• High event: 28 psig, differential: 2 psig

• High event: 2 psig, differential: 2 psig

• High event: 28 psig, differential: 26 psig

• High event: 2 psig, differential: 28 psig.