How to Inspect Vehicles A/C Expansion Valve?

If you need dis-assembly or replacement instructions for any other auto/car part, or you want to ask question related to your car/truck jeep problem then please leave the comment with your details, so I can provide you the required instructions and solutions.


The AC Expansion Valve is the component of a refrigeration system that regulates the rate of flow of refrigerant into the evaporator as governed by the action of the remote bulb-sensing tailpipe temperatures.


The procedure to inspect AC expansion Calve is as follows :-----

To raise pressure, there must be a restriction in the air conditioning system. The restriction divides the system into the high side and the low side. The terms high side and low side refer to the high pressure and low pressure within the system.

The flow control can be either an orifice tube or a metering device called an expansion valve. A thermostatic expansion valve controls the amount of refrigerant that is allowed to flow to the evaporator. A temperature sensing bulb on the evaporator inlet controls the expansion valve.

• A bad expansion valve will cause low readings on both the low and high side.
• Failure of the sensing bulb is the most common problem.
• Sometimes the valve can become plugged with debris.
• If the sensing capillary tube is warm, there is high pressure that pushes on the diaphragm.
• The sensing bulb checks the temperature of the outlet line of the evaporator.
• If it is warm, it opens the valve.
• Pressure on top of the diaphragm tries to push the valve open.
• The operation of the expansion valve can be checked.
• Some expansion valves can be cleaned, repaired or adjusted.

This system uses an expansion valve as it's flow control device.

Some expansion valves are wrapped with insulation. When the sensing bulb is in the evaporator case, it does not need to be wrapped because it stays cold. When an expansion valve is packed in that type of system, it is only to silence the noise that the evaporator makes.

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Also if you have better understanding of other car AC cooling system parts,then it will help more to troubleshoot the problem.

Check the list below or more help.

Its always advisable to know the AC components working and testing procedure,before replacing any part.

For more details regarding cars AC components.Check out the list of links below:---

How to Perform Car AC Leak detection Test?

http://repairhelpcenter.blogspot.com/2011/11/how-to-perform-car-ac-leak-detection.html

How to Perform AC Pressure Test?

http://repairhelpcenter.blogspot.com/2011/11/how-to-perform-ac-pressure-test.html

How to test Cars AC System?

http://repairhelpcenter.blogspot.com/2011/11/how-to-test-cars-ac-system.html

How to inspect Vehicles A/C Compressor and Clutch?

http://repairhelpcenter.blogspot.com/2011/11/how-to-inspect-vehicles-ac-compressor.html

How to Troubleshoot Vehicles AC Cooling Problem?

http://repairhelpcenter.blogspot.com/2011/11/how-to-troubleshoot-vehicles-ac-cooling.html

How to Replace Vehicles A/C Compressor and Clutch Components?

http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-vehicles-ac-compressor.html

How to inspect Vehicles A/C Condenser?

http://repairhelpcenter.blogspot.com/2011/11/how-to-inspect-vehicles-ac-condenser.html

How to Service Car AC Condenser?

http://repairhelpcenter.blogspot.com/2011/11/how-to-service-car-ac-condenser.html

How to Replace Auto AC Condenser?

http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-auto-ac-condenser.html

How to Replace Vehicles A/C Evaporator Core?

http://repairhelpcenter.blogspot.com/2011/11/how-to-replace-vehicles-ac-evaporator.html

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For car AC related and Heater related solutions. You can refer the options mentioned below:---

Car AC Blows Warm Air ?

http://technoanswers.blogspot.com/2011/10/car-ac-blows-warm-air.html

How to test AUTO AC pressure?

http://howtobyme.blogspot.com/2011/10/how-to-test-auto-ac-pressure.html

AUTO Air Conditioning Troubleshooting?

http://technoanswers.blogspot.com/2011/10/auto-air-conditioning-troubleshooting.html

AUTO A/C COOLING PROBLEM?

http://technoanswers.blogspot.com/2011/10/auto-ac-cooling-problem.html

Fixing refrigerant leak?

http://howtobyme.blogspot.com/2011/10/how-to-fix-refrigerant-leak.html

How to locate Car AC Refrigerant leak?

http://technoanswers.blogspot.com/2011/10/how-to-locate-car-ac-refrigerant-leak.html

CAR AC INTERMITTENT COOLING?

http://technoanswers.blogspot.com/2011/10/car-ac-intermittent-cooling.html

What causes INTERMITTENT COOLING on Car AC system?

http://technoanswers.blogspot.com/2011/10/what-causes-intermittent-cooling-on-car.html

Car AC making Noise?

http://technoanswers.blogspot.com/2011/10/car-ac-making-noise.html

BAD ODOR ON CAR AIR CONDITIONER?

http://technoanswers.blogspot.com/2011/10/bad-odor-on-car-air-conditioner.html

How to Recharge Car's Air Conditioner

http://repairhelpcenter.blogspot.com/2011/10/how-to-recharge-cars-air-conditioner.html

For details regarding:--

How does Vehicles Engine cooling system works?

http://repairhelpcenter.blogspot.com/2011/11/how-does-vehicles-engine-cooling-system.html

Engine cooling components working?

http://repairhelpcenter.blogspot.com/2011/11/engine-cooling-components-working.html

How to flush cars radiator?

http://repairhelpcenter.blogspot.com/2011/11/how-to-flush-cars-radiator.html