How Air Conditioning Systems Work: A Comprehensive Explanation

An air conditioning system is a complex network of components that work together to cool and condition the air inside a vehicle. At its core, an air conditioning system uses an engine-driven AC compressor to compress hot gas refrigerant. This compressed gas then travels through the AC condenser located up front, where it releases some of its heat. Despite being still a hot gas at this point, the refrigerant is now in a liquid state.

The next step in the process is to send the hot but still liquid refrigerant through an expansion valve or one of several other systems that allow for expansion and cooling. This allows the refrigerant to change state from a liquid back into a gas as it absorbs heat from the surrounding air. The purpose of this valve is to reduce the pressure of the refrigerant, allowing it to expand and cool further.

There are different types of systems used for this expansion process, but one common method is sending the cooled refrigerant through a cabin evaporator if you want to cool the passengers off or sending it through a power chiller to cool off the air going into the engine. It's essential to note that turning on the AC while running down the drag strip may not be beneficial as it can reduce the amount of power available for acceleration.

However, in this specific application, the air conditioning system is actually beneficial because it allows the coolant to travel through a liquid-to-liquid cooling circuit and cool the intake air. This process alone reduces the temperature of the air by 10 degrees Celsius. When considering the entire system, including the heat exchanger and electric pump, the total reduction in temperature can reach as low as 45 degrees Fahrenheit or a differential of 25 degrees Celsius.

The Power Chiller: A Key Component

One crucial component that enables this level of cooling is the power chiller. This device uses refrigerant to pull out energy from the air and cool it down. The power chiller alone can reduce the temperature of the intake air by an additional 10-15 degrees Celsius, depending on its specifications.

The question remains whether the power chiller will be running when the AC system is activated, especially during high-performance driving like drag racing. Fortunately, this system does have a clutch connected to the engine, which allows it to run as long as the engine RPM stays below 4,500 rpm. This means that even while driving at high speeds, the power chiller can continue to provide cooling benefits.

How Engine Power Improves Performance

Using an air conditioning system to cool the intake air has a direct impact on performance. By advancing the timing and allowing for denser air to enter the engine, more power is produced. This is because the cooler air allows for better combustion efficiency and increased energy release from the fuel. In essence, the AC system becomes an integral part of the engine's cooling process.

The After-Run Cooler: A Final Touch

Once the vehicle has finished its run on the drag strip, it's essential to prevent heat soak in the intake air. The after-run cooler addresses this concern by continuing to run the engine cooling fan and electric pump to maintain a cool temperature. This ensures that when the vehicle is restarted, it will have access to fresh, cooled air instead of hot exhaust gases.

In conclusion, modern air conditioning systems are incredibly sophisticated, with various components working together in harmony to provide optimal performance and comfort. By leveraging engine power to drive this cooling process, manufacturers can create vehicles that not only cool their occupants but also improve overall performance.

"WEBVTTKind: captionsLanguage: enhello everyone and welcome in this video we're going to be talking about how the dodge challenger demon uses the air conditioning system to create more power now i had the pleasure of driving the dodge demon on a drag strip and i also got to chat with several of the engineers who worked on the project to learn about how this system works and you know you're probably intuitively thinking uh how does you know using engine power to create more engine power work but we'll get into how the entire system works and why it is possible um based on the discussions i had with their engineers and you know looking at this it definitely looks confusing at first glance uh this is kind of an exploded view of what's going on there's three different cooling systems we're going to be talking about here and we'll definitely make sense of it all by the end of this video i promise that uh and so you know looking at it the three systems we've got the engine in black uh so that's the engine cooling with the black circuit here we've got the intercooler which is in purple that's got a cooling system all of that in purple and then the air conditioning system is in brown and this isn't an exact replica of what's going on in the car but it's close enough to where we can understand uh what's happening and how they're implementing this system so starting off with the very first thing let's look at the engine you've got of course your ambient air coming in through the air filter it goes through the supercharger that compresses that air heats it up so you've got hot air you don't want to put hot air in the engine that's less dense more likely to have knock so you run it through an intercooler then you have cooler air and send that air into the engine now the engine gets its cooling using a radiator like all the other internal combustion engines out there so you've got a water pump which will be pulling uh fluid from the engine radiator and then pumping that fluid through the circuit so you've got hot liquid coolant coming out and then the cooled liquid which will be cooled by the ambient air that radiator mounted at the front of the vehicle now your second system you have is the intercooler so it has its own cooling circuit the engine has a uh engine driven water pump however the intercooler is using an electric pump so it's driven by the battery ultimately and so that intercooler you've got your hot liquid coolant after that air is exchanged to cool down the air that's going into the engine so the hot coolant comes out passes through your heat exchanger up front you've got ambient air passing through that heat exchanger and then that cools it down it goes through an electric pump through a power chiller and then into the intercooler we'll get into the power chiller in a bit up front is where you have your stack of the radiator the ac condenser the heat exchanger for the intercooler and you'll also have an engine cooling fan and this isn't exactly accurately drawn it's going to be much more compact and the engine cooling fans will pull in air through the entire thing and then your third system your ac system and some of the components are left out just to make it simpler to understand i have a separate video explaining how air conditioning systems work but essentially you have an engine driven ac compressor that's going to compress hot gas refrigerant which will then travel through the ac condenser up front you'll put some remove some of that heat it's still going to be a hot but now it will be liquid refrigerant you'll then send that through an expansion valve or there are other systems that you can use in order for that liquid to expand and then cool and so as it changes state you've got this little valve right here simplified version but basically you can send it through the cabin evaporator if you want to cool the passengers off or you can send that refrigerant that's been chilled through your power chiller to cool off the air going into the engine now it's one or the other so you're not going to be turning on your ac while you're running down the drag strip and getting the benefit of that which is fine you know you don't want to be drawing the ac just to cool you off you want to be using it if anything to make more power if not just turn it off so you have maximum power but in this case you actually want it on so that will travel through you have this liquid to liquid well essentially liquid the the coolant the refrigerant will eventually turn into a gas as it expands going through that power chiller and then you've got cool liquid coming from the electric pump for the intercooler circuit and then as it goes through the power chiller you use that ac uh coolant uh to actually have a cold liquid coolant travel into the intercooler to cool down this air now the power chiller alone running that ac system can reduce uh the temperature of the air by 10 degrees celsius and the entire system using the heat exchanger and the electric pump the entire system can lower by lower it by 45 degrees fahrenheit or a differential of 25 degrees celsius that's their claims on the amount that they can reduce this intake air temperature going into the engine now a question you may have is is this power chiller going to be running is the ac system going to be running while you're going down that drag strip and in fact it is this ac compressor has a clutch connected to the engine and so as long as the engine rpm is under 4 500 rpm you will in fact be running this circuit this ac circuit and cooling that liquid coolant that's traveling through the intercooler using the power chiller so pretty cool that it actually does benefit now the question you have of course is wait so you're using engine power to create more engine power and yes that's actually exactly what you're doing it's the same idea with the supercharger so the supercharger actually takes about 90 horsepower to run but it gives you one bar of pressure so much more air that you can pack into the engine and as a result you make more power than the losses that it takes to run the supercharger is it super efficient not necessarily same with the ac system it's not an efficiency improvement but it is a power improvement and so you're able to chill that air enough that you're it's denser and you're also able to advance the timing more and as a result of that the power that you put in into chilling that air uh will result in greater power output from the engine beca because you're able to advance that timing as a result of the cooler intake air so pretty neat how that works and pretty neat that it actually is beneficial and finally let's get into this after run cooler so once you run down the drag strip you're turning around you're coming back you're going to start waiting in line or let's say you're just going to go take a break and you're going to shut your car off so you shut your car off and you don't want that to heat soak the intake air so the next time you go for a run that air is really hot so what the system does this after run cooler is because the pump is electric and the fan is electric you can continue to run that engine cooling fan and the electric pump and you'll continue to run this cooler temp circuit here for the intercooler to make sure that when you do start back up you're not going to have super hot intake air temperatures so pretty neat that they do that that's the after run cooler portion and then the srt power chiller that's this device right here which is used to bring that down which you could you know potentially get below ambient because you're using refrigerant uh rather than relying purely on the ambient air that's passing through the front heat exchanger in order to pull out that energy so a really neat system pretty cool to see this first time this has been done in a production vehicle if you guys have any questions or comments feel free to leave them below thanks for watching umhello everyone and welcome in this video we're going to be talking about how the dodge challenger demon uses the air conditioning system to create more power now i had the pleasure of driving the dodge demon on a drag strip and i also got to chat with several of the engineers who worked on the project to learn about how this system works and you know you're probably intuitively thinking uh how does you know using engine power to create more engine power work but we'll get into how the entire system works and why it is possible um based on the discussions i had with their engineers and you know looking at this it definitely looks confusing at first glance uh this is kind of an exploded view of what's going on there's three different cooling systems we're going to be talking about here and we'll definitely make sense of it all by the end of this video i promise that uh and so you know looking at it the three systems we've got the engine in black uh so that's the engine cooling with the black circuit here we've got the intercooler which is in purple that's got a cooling system all of that in purple and then the air conditioning system is in brown and this isn't an exact replica of what's going on in the car but it's close enough to where we can understand uh what's happening and how they're implementing this system so starting off with the very first thing let's look at the engine you've got of course your ambient air coming in through the air filter it goes through the supercharger that compresses that air heats it up so you've got hot air you don't want to put hot air in the engine that's less dense more likely to have knock so you run it through an intercooler then you have cooler air and send that air into the engine now the engine gets its cooling using a radiator like all the other internal combustion engines out there so you've got a water pump which will be pulling uh fluid from the engine radiator and then pumping that fluid through the circuit so you've got hot liquid coolant coming out and then the cooled liquid which will be cooled by the ambient air that radiator mounted at the front of the vehicle now your second system you have is the intercooler so it has its own cooling circuit the engine has a uh engine driven water pump however the intercooler is using an electric pump so it's driven by the battery ultimately and so that intercooler you've got your hot liquid coolant after that air is exchanged to cool down the air that's going into the engine so the hot coolant comes out passes through your heat exchanger up front you've got ambient air passing through that heat exchanger and then that cools it down it goes through an electric pump through a power chiller and then into the intercooler we'll get into the power chiller in a bit up front is where you have your stack of the radiator the ac condenser the heat exchanger for the intercooler and you'll also have an engine cooling fan and this isn't exactly accurately drawn it's going to be much more compact and the engine cooling fans will pull in air through the entire thing and then your third system your ac system and some of the components are left out just to make it simpler to understand i have a separate video explaining how air conditioning systems work but essentially you have an engine driven ac compressor that's going to compress hot gas refrigerant which will then travel through the ac condenser up front you'll put some remove some of that heat it's still going to be a hot but now it will be liquid refrigerant you'll then send that through an expansion valve or there are other systems that you can use in order for that liquid to expand and then cool and so as it changes state you've got this little valve right here simplified version but basically you can send it through the cabin evaporator if you want to cool the passengers off or you can send that refrigerant that's been chilled through your power chiller to cool off the air going into the engine now it's one or the other so you're not going to be turning on your ac while you're running down the drag strip and getting the benefit of that which is fine you know you don't want to be drawing the ac just to cool you off you want to be using it if anything to make more power if not just turn it off so you have maximum power but in this case you actually want it on so that will travel through you have this liquid to liquid well essentially liquid the the coolant the refrigerant will eventually turn into a gas as it expands going through that power chiller and then you've got cool liquid coming from the electric pump for the intercooler circuit and then as it goes through the power chiller you use that ac uh coolant uh to actually have a cold liquid coolant travel into the intercooler to cool down this air now the power chiller alone running that ac system can reduce uh the temperature of the air by 10 degrees celsius and the entire system using the heat exchanger and the electric pump the entire system can lower by lower it by 45 degrees fahrenheit or a differential of 25 degrees celsius that's their claims on the amount that they can reduce this intake air temperature going into the engine now a question you may have is is this power chiller going to be running is the ac system going to be running while you're going down that drag strip and in fact it is this ac compressor has a clutch connected to the engine and so as long as the engine rpm is under 4 500 rpm you will in fact be running this circuit this ac circuit and cooling that liquid coolant that's traveling through the intercooler using the power chiller so pretty cool that it actually does benefit now the question you have of course is wait so you're using engine power to create more engine power and yes that's actually exactly what you're doing it's the same idea with the supercharger so the supercharger actually takes about 90 horsepower to run but it gives you one bar of pressure so much more air that you can pack into the engine and as a result you make more power than the losses that it takes to run the supercharger is it super efficient not necessarily same with the ac system it's not an efficiency improvement but it is a power improvement and so you're able to chill that air enough that you're it's denser and you're also able to advance the timing more and as a result of that the power that you put in into chilling that air uh will result in greater power output from the engine beca because you're able to advance that timing as a result of the cooler intake air so pretty neat how that works and pretty neat that it actually is beneficial and finally let's get into this after run cooler so once you run down the drag strip you're turning around you're coming back you're going to start waiting in line or let's say you're just going to go take a break and you're going to shut your car off so you shut your car off and you don't want that to heat soak the intake air so the next time you go for a run that air is really hot so what the system does this after run cooler is because the pump is electric and the fan is electric you can continue to run that engine cooling fan and the electric pump and you'll continue to run this cooler temp circuit here for the intercooler to make sure that when you do start back up you're not going to have super hot intake air temperatures so pretty neat that they do that that's the after run cooler portion and then the srt power chiller that's this device right here which is used to bring that down which you could you know potentially get below ambient because you're using refrigerant uh rather than relying purely on the ambient air that's passing through the front heat exchanger in order to pull out that energy so a really neat system pretty cool to see this first time this has been done in a production vehicle if you guys have any questions or comments feel free to leave them below thanks for watching um\n"