The difference in temperature between the refrigerant condensing temperature and the ambient air blowing over the condenser coil is called _______.

During standard operating conditions, there will be approximately a ____°F wet-bulb drop from the evaporator inlet to the evaporator outlet.

The humidity in the air at the evaporator outlet will be at almost ____%.

For a system that utilizes a R-410A compressor, the discharge line may be as hot as _____°F under normal conditions. Care must be taken when attaching a thermometer.

Manufacturers report that a fairly high percentage of compressors returned to them under warranty are actually not defective but were reported by the technician as defective.

A standard efficiency system usually has a refrigerant boiling temperature of about ____°F cooler than the entering-air temperature at standard operating conditions.

If a condenser is located under a deck, air may be circulated back through the condenser and cause ________.

On small systems, a technician should not connect a gauge manifold every time the system is serviced.

The gauge manifold displays low- and high-side pressures that can be converted to _________ temperatures using a T/P chart.

As a rule of thumb, the air leaving the evaporator will be about ____ than the air entering the evaporator.

A service valve can be used to ____.

A typical evaporator superheat reading at the evaporator outlet for a central air-conditioning system on a 95°F day would be ____°F.

On a 95°F day, the R-22 refrigerant pressure on the high side should be about ____ psig.

The liquid line temperature is used to determine the ____ of a condenser.

To accurately add refrigerant to a system, a condenser ambient temperature of ____°F should be simulated.

The instrument to use to check for a short in the compressor motor winding is a(n) ____.

With a rise in outdoor temperature, the head pressure will rise.

Superheat occurs in the condenser as well as the evaporator.

The best way to tell if a compressor's discharge line is at the correct temperature is to grab hold of it.

Subcooling occurs in the evaporator as well as the condenser.

When checking the electrical circuits of an air-conditioning system, each parallel circuit should be isolated and checked separately.

If a compressor has a partially shorted winding, it could run for a while, overheat, and shut off.

Reducing the CFM through the evaporator will cause the head pressure to ____________________.

On most gauge manifolds, the suction or low side gauge is located on the ____________________.

Two types of fixed-bore metering devices are capillary tubes and _________________________.

Reducing the CFM through the evaporator will cause the amperage draw of the compressor to ____________________.

A ____ reacts to stop, start, or modulate the flow of water, air, or refrigerant to the system or conditioned space

All control systems can be subdivided into ____, no matter how many controls there are.

____ control systems were used before electronics.

Pneumatic controls must have a permanent air supply that is ____.

Most system compressors provide ____ psig of air pressure to the storage tank.

In most system compressors, the compressors are controlled with a ____.

A ____ is either in the pressure reducer or in the downstream side of the system to ensure that the control air pressure does not exceed about 30 psig.

In a(n) ____ loop, all changes happen within the loop.

A device called a ____ is used to control the large volume of air in a air conditioning system.

The pilot positioner has a main air supply that is governed by the ____.

Controlling the water flow to the room’s needs is called ____.

The temperature in the room is known as the ____ air temperature.

Electronic controls are commonly called ____.

The controlled environment could be controlled by an array of ____ such as dampers, fans, variable-frequency drives.

____, usually housed internally inside the controller, convert the information from either analog to digital (A/D) or digital to analog (D/A) format.

The very first control systems were used to start and stop the various components.

Space temperature is the only temperature that is important in modern systems.

Modern control systems only have on-off control capability.

Today control output devices can receive signals as either analog or digital.

Controllers are devices that can measure some type of environmental parameter or a controlled variable and convert this parameter to a value that the controller can understand.

DDC is a control process in which a microprocessor, acting as a digital controller, constantly updates a database of internal information.

The ____________________ is the device that responds to a change in conditions.

In a home air-conditioning system, the ____________________ is the sensor.

Desiccant driers use some of the same products that refrigerant driers use, silica gel or molecular sieve as an adsorbent.

A control can be which of the following?

An example of a power consuming device would be a(n) ____ while an example of a non-power consuming device would be a(n) ____.

An electrical power consuming component ____.

The line side of a switch is the ____.

If an air conditioning system is calling for cooling and the compressor is running but the indoor (evaporator) fan is not running, which terminal on the thermostat will the technician most likely check first?

The _____ is nothing more than a set of switches.

The continuity through a heat relay is checked using a(n) ____.

A 10-wrap amperage multiplier is used with a(n) ____.

Transformers are rated using ____.

A(n) ____ is the easiest diagram to use to follow a circuit. This diagram normally can be studied briefly, and the circuit function should become obvious.

An electrical diagram showing the approximate location of the components is called a(n) ____.

If line one of a circuit had a potential of 120 V and line two was neutral, the potential voltage (difference) between line one and line two would be zero volts.

The heat anticipator in a thermostat is usually an adjustable type.

The cooling anticipator in a thermostat is usually an adjustable type.

When checking thermostat circuits, an insulated jumper wire is a handy tool.

When conditions are correct, the rheostat will pass power through the device onto the system components to be controlled.

While troubleshooting a 24-V control circuit consisting of a thermostat, a pressure control, and a contactor coil, the technician reads 24 volts across the thermostat, 0 volts across the pressure control, and 0 volts across the contactor coil. The technician makes the following statements. The following statements are all considered to be true.

A) The transformer is burned out.

B) The thermostat is open.

C) The contactor coil is energized.

A 120-V/24-V control transformer has a VA rating of 20. The maximum amperage the transformer will put out is 0.8 amps.

When using a ten-wrap multiplier, the reading on the meter must be multiplied by ten.

The purpose of a heat anticipator is to ____.

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

What is meant by the term "detent"?

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

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

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

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.

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

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

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?

If the suction pressure of a system is 60 psig and the oil pump outlet is 85 psig, what is the net oil pressure?

Oil pressure safety controls measure the difference in pressure to establish ____.

To prove that the combustion blower motor is operating before ignition, a ____ would be used.

To control ice build-up on a heat pump outdoor coil in the heating cycle, a ____ is attached to a large diaphragm.

Where would a water regulating valve that is controlling head pressure be installed?

When a water-regulating valve is used to control the head pressure of a water-cooled system, the valve's spring acts against which pressure to modulate the water flow?

The heat anticipator in a thermostat prevents the temperature in the conditioned space from rising above the thermostat setting.

The cold anticipator starts the cooling system early to allow the air-conditioning system to get up to capacity when needed.

The advantage of using a thermistor-type thermometer over a mercury-filled thermometer for measuring refrigerant line temperature is that the thermistor-type does not have to be insulated.

A helix coil is used in some applications to sense temperature in a moving air stream.

A dual pressure control is actually a low pressure control and a high pressure control connected in parallel with each other.

Many natural gas fired heating units operate at a manifold pressure of 3.5 in. WC.

The automatic control of a system is intended to ____.

Modulating controls are used to ____.

When a control is required to control space or product temperature, it is called a ____.

A thermal system overload may occur if a specific electrical or mechanical component is not cooled properly, resulting in ____.

Devices, such as thermostats, that open and close their contacts during the ____ operation of the system are referred to as operational controls.

The compressor in the refrigerator has a protective device that keeps it from overloading and damaging itself. This device is called a(n) ____.

The metals most often used in a bimetal temperature control are ____.