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How do you change an orifice tube?

How do you change an orifice tube?

Here are some steps to replace the orifice tube in your vehicle.

  1. Step 1: Become Familiar with AC Unit.
  2. Step 2: Locate Orifice Tube.
  3. Step 3: Disconnect Tube from Orifice Tube.
  4. Step 4: Remove Seal from Line.
  5. Step 5: Remove Orifice Tube.
  6. Step 6: Install New Orifice Tube.
  7. Step 7: Install Seal.
  8. Step 8: Charge the System.

Where is the orifice valve located?

One of the many parts that can fail within your vehicle’s air conditioning, is the orifice tube. This tube is also known as the expansion tube, and is located within the tube between the condenser and the evaporator. It has 1 side that is a little smaller than the other, to supply more pressure.

Are all orifice tubes the same?

While you may have a personal preference of a blue orifice tube going on your truck rather than a yellow or brown one, the colors do matter. Orifice tube colors correspond to the orifice diameters of different makes and models of trucks. So when you need to replace this part, not just any color will do.

Is orifice tube on high side or low side?

An orifice tube is used to control the flow of refrigerant into the evaporator. It works in conjunction with compressor controls to maintain low side pressure at a sufficient level, to prevent evaporator icing or flooding. The orifice tube is placed in the high side liquid refrigerant line, at or near the evaporator.

Will a bad orifice tube cause high pressure?

If the filter’s filled with white or brownish debris, the desiccant bag in the accumulator has broken, sending desiccant throughout the system. This restriction will cause high high side system pressures.

What is the purpose of an orifice?

An orifice plate is a device used for measuring flow rate, for reducing pressure or for restricting flow (in the latter two cases it is often called a restriction plate). Either a volumetric or mass flow rate may be determined, depending on the calculation associated with the orifice plate.

How do you identify an orifice in the pipeline?

The paddle will be engraved with the diameter of the restriction in the plate and sometimes the material of construction. The engraved side of the paddle faces the upstream side of the flow stream to ensure that the orifice is inserted in the correct orientation.

What happens when flow through an orifice is increased?

The mass flow rate can still be increased if the upstream pressure is increased as this increases the density of the gas entering the orifice….Choking in change of cross section flow.

, pressure drop across constriction (unit force per unit area)

What are the types of orifice?

There are 4 types of Orifice Plates that we will discuss:

  • Concentric Orifice Plate (Hole is in the center)
  • Eccentric Orifice Plate (Hole is off center)
  • Segmental Orifice Plate.
  • Others – such as Conical and Quadrant, and Edged Entrance types.

Which is the main disadvantage of orifice meters?

Disadvantages of orifice meter: It requires the flow of axial velocity vectors. It causes a pressure drop in the fluid. Its accuracy is affected by the density, pressure and viscosity of the fluid. The range of measurement of viscosity limits of fluids.

What are the advantages and disadvantages of orifice plates?

Advantages and disadvantages of orifice plate

  • Simple in construction, the standards for construction and calibration are readily available.
  • They are cheap; their price does not increase dramatically with size.
  • Easy to install and remove.
  • They are efficient and reliable for many years.
  • Available in many materials.

Which is better Venturi or orifice?

The Venturi meter can handle large range of flow rates of fluid than the Orifice meter but once the Venturi meter is installed the range of flow rates it can handle becomes fixed. Thus, Orifice meters offer much more flexibility of operation.

Why is Venturimeter preferred over orifice meter?

1. Both are used to calculate the velocity of a fluid. A venturi meter can be used to measure the flow rates of all incompressible fluids (gases with low pressure variations, as wells as liquids), whereas an orifice meter is generally used for measuring the accelerated flow through the apparatus.

Where is the AC orifice tube location?

Some systems are designed so that the orifice tube is mounted in the high side of the liquid refrigerant line in the evaporator. In some systems, the orifice tube can be mounted in the condenser outlet, which can soften the hissing noises that traditionally are produced when this type of A/C system is turned off.

Where is the fixed orifice located?

A fixed orifice tube contains a small brass tube encased in a plastic case with a filter at each end to protect it from any debris in the system. It’s located on the high side between the condenser and the evaporator core.

How do I know if my orifice tube is bad?

Symptoms of a Bad or Failing Expansion Valve (Orifice Tube)

  1. AC system performing worse than usual and blowing warm air. One of the first symptoms of a problem with the AC expansion valve or orifice tube is an underperforming AC system.
  2. Frost on AC evaporator or coming from the vents.
  3. AC compressor constantly running.

Do you have to replace orifice tube?

Car air conditioning systems need the expansion valve, or orifice tube, replaced if the AC is blowing warm air or the AC system is broken.

Will AC work without orifice tube?

Faulty orifice tubes can also result in too little refrigerant flow through the evaporator. If this is the case, the flow of refrigerant will not be enough to absorb the heat that is coming from the condenser. When this occurs, the A/C simply will not be performing well enough to allow the system to cool.

What happens if orifice tube is backwards?

All the refrigerant has to go through the . 071 hole. So, it will work if installed backwards. If installed backwards it will suck to remove, and if there is debris in the system the screen has very little surface area so it will plug easily.

What are the symptoms of a bad AC drier?

Bad A/C receiver drier symptoms

  • Unusual noises.
  • Leakage.
  • Bad odour.
  • Ineffective cooling.
  • Cloudy sight glass.

When should I replace my AC receiver drier?

The receiver dryer must be regularly replaced. It is recommended that the receiver dryer is replaced every second year or whenever the circuit has been opened. Always install a new receiver dryer any time the compressor is replaced and always when a serious leakage has been noticed and repaired.

When should I change my AC filter drier?

All filter driers should be replaced every 2 years or by manufacturer’s recommendation. The Receiver Drier’s function in an automotive a/c system is to filter foreign material, remove moisture from refrigerant and to act as a reservoir to supply liquid refrigerant to the TX valve.

Is an AC drier and accumulator the same thing?

Receiver/Dryer or Accumulator A receiver/dryer is used on vehicles that have a thermal expansion valve. Accumulators are in vehicles that have an orifice tube. The receiver/dryer is responsible for separating gas from liquid.

What does a AC accumulator do?

The accumulator has different roles: To provide compressor protection, preventing compressor failure due to liquid slugging. To retain moisture and contaminants from the system (during the accumulator’s lifetime) To ensure oil return and ensure that only refrigerant is returning to the compressor.

How do you know if you overcharge your AC?


  1. Lower Cooling than Usual. This is the top symptom that relays the message to you that your AC is overcharged.
  2. No Air Coming Out.
  3. High Pressure Reading.
  4. Abnormal Compressor Noises and also Compressor Damage.
  5. Engine Complications.
  6. The Compressor is Busted.
  7. Overheating.

What does a accumulator drier do?

As part of the air conditioning system, the AC accumulator-drier transforms liquid refrigerant from the evaporator into gas form (without refrigerant oil and debris) to the AC compressor.