Metering devices

A yellow handle

A manual expansion valve can be identified by

Constant pressure valve

Another name for an automatic expansion valve is

The percentage of liquid to vapor cannot be determined

When a refrigerant is saturated, indicated by a pressure and temperature match on a P/T chart

The superheat rises causing the TXV to feed more refrigerant

What is the effect of an increase in the cooling load on a TXV

Increased pressure differential

A fixed-orifice metering device increases the flow of refrigerant in response to a

Converts high-pressure high temperature liquid refrigerant in to low pressure low temperature mix of vapor and liquid

A metering device is a refrigerant circuit device that

Electronically controlled expansion valve

A stepper motor changes the expansion valve opening in the

The amount of surface area bathed in boil liquid

Evaporator cooling capacity is significantly affected by

It is not capable of preventing floodback

How does an automatic expansion valve prevents liquid floodback in a system

Evaporator will be starving of refrigerant

If a capillary tube is restricted due to a sharp bend,the

A superheated refrigerant

In a DX system operating normally, the refrigerant leaving the evaporator should be

Decrease

In a comfort cooling system with a fixed metering device, as the heat load reduces, the superheat will

A system with a fairly constant load

In which of these applications would a manual expansion valve be a good choice

Refrigeration system with a defrost cycle

Maximum operating pressure expansion valve are manly used on

Has a sensing bulb filled with refrigerant or another thermostatic fluid

One distinguishing feature of the TXV is that it

Solenoid valves

Pulsing and analog expansion valves are special design based on

TD between the coil and cooled medium is lower

Superheat setting for low-refrigerant systems are typically Lower because the

Gradual decrease on suction temp and an increase in superheat

The best clue to the problem of moisture freezing at an expansion device is a

Setting the room thermostat abnormally low

The condition most likely to cause floodback when a fixed metering device is in use

Digital linear actuator

The device that converts an EEV motor rotation to a back and forth motion is known as

Downstream of, and near, the sensing bulb

The equalizer line of an externally equalized TXV is best to attached

Condenser coil capacity

The primary factor in determining the size of a fixed-orifice metering device is typically the

Feed equal amounts amounts of refrigerant to the evaporator circuits

The primary purpose of a distributor in an air conditioning system is to

A very low suction pressure

The symptoms that most likely indicated the thermostatic element of a TXV has lost its charge is

The system must be in operation

When changing the superheat setting on a TXV

An externally equalize TXV

Which of the following is best suited for a system with large pressure drops across the evaporator coil

They have no sensing bulb

Which of the following is true of capillary tubes

More sub-cooling improves the efficiency and capacity of the system

Which of the following statements about metering devices is true

The pressure drop through the valve has a significant effect on its capacity

Which of the following statements is true regarding TXV selection

Many distributors have a replaceable orifice

Which of the following statements is true regarding distributors

Clogged condenser coil will reduce or prevent surgery sub-cooling

Which of the following statements statements about metering devices are true