How does automotive ac system work

You can think of it as similar to the nozzle on the end of a hose, high-pressure water is introduced, and it expands into a mist as it passes through. On an AC system featuring an orifice tube, the receiver dryer is replaced with an accumulator.

It works similarly to a receiver dryer but sits between the evaporator and the compressor instead. The difference between an orifice tube and an expansion valve is that the former has a fixed opening.

And the latter can regulate its opening depending on the temperature in the evaporator. By this point, the refrigerant is now in a low-pressure, low-temperature state, nearly ready to cool your passenger cabin. But first, it has to pass through the evaporator.

The evaporator works much like a radiator or a condenser, containing lines that the refrigerant flows through. As this happens, rather than dissipating heat, it absorbs it, lowering the temperature to about degrees. Oddly enough, unlike water, which freezes at degrees, the refrigerant boils.

This converts it back into a gaseous state, allowing it to absorb even more heat. This gas then flows back into the AC compressor to start the process over again. How does cold air enter the cabin when the AC is on? While the refrigerant is sitting in the evaporator, a fan is blowing outside air over it. This causes it to cool due to the low temperature inside. It promotes the pressure of the refrigerant so that it can transform vapour refrigerant into a liquid refrigerant.

The liquid refrigerant enables the overall flow of air through the condenser. Condenser The condenser is a small device that controls the condensing. This force helps in controlling it. Expansion Valve Expansion Valve helps in expanding the high pressure, by sending low-temperature liquid refrigerant by the condenser. As its name implies, it controls the expansion and reduces the pressure.

The release pressure of the refrigerant before sending it to the evaporator. Evaporator The evaporator is placed behind the AC vent and looks like the heat exchanger. It takes the heat from the car and converts it into liquid refrigerant by changing it into vapour. Orifice Tube The orifice tube is in the shape of a cone and provided restriction in the flow of refrigerant.

It allows the refrigerant to convert high to low-pressure liquid refrigerant mist before entering the evaporator. Receiver Dryer Receiver Dryer is known as the safety catch as it maintains the safety in the car. When we are using the Air conditioner, sometimes liquid starts flowing towards the compressor instead of vapours, which can damage the compressor. So the receiver dryer is used inserted between compressor and evaporator to transform the remaining liquid into vapours and then send it for compression.

AC Inline Filter Air conditioning inline filter kit traps wreckage and gives you the cleaned air. AC Refrigerant Refrigerant has a low boiling point and is used by the AC as a heat exchanging medium. It is in the fluid form, so changing the temperature becomes very easy through it. At low temperatures, the refrigerant converts into gaseous form, while it stays liquid at the high temperature. Accumulator Accumulator holds the refrigerant.

It desiccant the refrigerants bag by removing moisture from it and then circulate it inside the car. You can only find the combination of these two in rear AC systems.

Now, you know about every component of the Car AC and we can move forward towards its process. We have tried to give sequential steps on how Car AC works. If your AC is not working in the same way, then you have you get it checked. The Orifice Tube and Accumulator system come with the orifice tube before the evaporator and accumulator before the compressor.

The Orifice Tube controls the refrigerant flow and controls the low-pressure mist before entering the evaporator. Whereas, accumulator holds the refrigerant and removes moisture from it to control the damage. Expansion Valve and Receiver-drier System The Expansion valve and receiver-drier system come with an expansion valve before the evaporator core and receiver-drier between the condenser and in-line filter kit.

The desiccant in this system absorbs the moisture. It works like the accumulator, but it is located on the high-pressure side rather than the low-pressure side.

The expansion valve works the same in both systems and restricts refrigerant flow to convert the liquid into the low-pressure mist. Why should you get your Car AC Inspected? Need for Car AC inspection Each person has different needs. Some love to sit in a warm environment, while some feel more comfortable in a cold environment. When you sit in your car, you can judge how much air do your AC is emitting.

If the water is allowed to remain and possibly form ice crystals, it can damage the air conditioning system. If you were to touch this part of the system, you'd feel it change from hot to cold.

The high-pressure liquid refrigerant flows from the receiver-dryer through the expansion valve, where it is allowed to expand. This expansion reduces the pressure on the refrigerant, so it can move into the evaporator. The valve senses pressure and regulates the flow of refrigerant, which allows the system to operate steadily, but the moving parts of the valve can wear out and sometimes require replacement.

Some vehicles have an orifice tube rather than an expansion valve, but it serves the same purpose in allowing the refrigerant to expand and the pressure to be lowered before the liquid enters the evaporator. The orifice tube allows refrigerant to flow at a constant rate and has no moving parts, but it can become clogged with debris over time.

Systems with an orifice tube automatically turn the AC system on and off to regulate the flow of refrigerant to the evaporator. Evaporator: This is where the magic happens. While all the other parts of the system are located in the engine compartment, this one is in the cabin, usually above the footwell on the passenger side. It also looks like a radiator, with its coil of tubes and fins, but its job is to absorb heat rather than dissipate it.

Refrigerant enters the evaporator coil as a cold, low-pressure liquid, ideally at 32 degrees Fahrenheit 0 degrees Celsius , which is why you don't want any water in the system. The refrigerant doesn't freeze at this temperature, but it does have a very low boiling point.

The heat in the cabin of the car is enough to make the Ra in the evaporator boil and become a gas again, just like water turning back to steam. In its gaseous form, refrigerant can absorb a lot of heat. The gas moves out of the evaporator -- and out of the passenger compartment of the car, taking the heat with it. A fan blowing over the outside of the evaporator coil blows cool air into the passenger compartment.

The refrigerant in gas form then enters the compressor, where it is pressurized and the whole process starts all over again.

If the system uses an orifice tube, there will be an accumulator between the evaporator and the compressor. An orifice tube sometimes lets too much refrigerant into the evaporator and it doesn't all boil.

Since the compressor cannot compress liquid, only gas, the accumulator traps any excess liquid before it can get into the compressor. The evaporator also takes humidity out of the air in the car, which helps you feel cool. Water in the air condenses on the evaporator coil, along with dirt and pollen and anything else floating around in the cabin.

When you stop the car and see water dripping underneath, it's probably the water from the AC evaporator and nothing to worry about.

Most of us start seeing ads in the spring for car repair shops offering deals on recharging your car's air conditioning in time for the coming summer. Which makes us ask, what is recharging the AC? Is it required, like an oil change? Does my car's air conditioning need to be recharged?

Is this another scam that repair shops can pull on unsuspecting customers? The answer to that last one is definitely no; recharging the AC is not a scam. It simply means that fresh refrigerant is added to the system. If the refrigerant is a bit low, it can be topped off, the same as if you were a bit low on oil in the engine.

If it's really low, though, whatever refrigerant is still in the system needs to be drained out and replaced. This process of clearing out the system and adding new fluid is called recharging.

In either case, you've lost some refrigerant, which isn't so great.