With the hot days of summer all around us, I can only think more about my AC system, and how does it work? Just hoping that it works to its fullest potential, so it can keep you nice and fresh. Let’s look further into this so we can better understand it. In the case that it doesn’t work this guide will walk you through diagnosing your problem so that you can get back in the cool breeze of your AC system again soon.
What parts does the ac system consist of?
First, before we understand all the technical points of our AC system, you need to know what parts consist of your system. Also, what their jobs in your AC system are.
Condenser
Your condenser plays a valuable role in your AC system, just as useful as your radiator’s role to your engine. Your condenser and radiator are very similar not only in jobs but in look as well. Your hot freon used and tired comes to your condenser as its last stop in a gas form.
Your freon will pass through the fine of the condenser, and they will shed the heat away. So much the freon will condense back into liquid form to continue back into the AC system to do it all over again.
After leaving the condenser back in its liquid state, the freon will advance to the evaporator inside your dashboard to continue on its journey.
Evaporator
Your evaporator sits next to your blower motor positioned deep in your dash. The evaporator plays a hidden but critical role in your AC system. The name of this part plays an ideal position in its actual function.
This part of the AC system is where the warm air is going to blow through your evaporator. In this process, your freon which is in a liquid form. The freon passes through the evaporator and evaporates the liquid back into a gas form.
The warm air passing through the evaporator is the cause of your freon being evaporated back into its gas form. The evaporator itself looks very similar to a radiator. By doing this, the air has turned into the sweet cold air you wanted.
The air that you enjoy so much on a hot summer day. This cycle will continue as long as your AC system is turned on.
Compressor
Your compressor is the engine in your AC system, putting the freon under pressure so it can start its journey through your AC system. The AC system begins with your condenser.
In this process, the freon has the chance to switch from a gas into a liquid. A fully functioning ac compressor is vital to your AC system working properly in your vehicle.
A/C Main relay
Controlled by the AC button in your vehicle, this relay is no different than any other relay. This relay supplies power to your AC compressor and the AC compressor clutch when you engage the vehicle AC system to be turned on.
Orifice Tube
If your AC system has an accumulator, then you have an orifice tube. This part meter’s a fixed rate of flow of refrigerant (freon) to your evaporator.
The Orifice tube will allow the refrigerant to expand, which in turn lowers the pressure of the refrigerant before being sent to the evaporator.
Low-Pressure switch
Your Low-Pressure switch is a safety switch that positioned on the low side of your AC system. In the situation that the pressure rises too high or drops too little in your system.
This switch will turn off your AC compressor to prevent any damage to your vehicle’s AC system.
High-pressure switch
The High-Pressure switch is a safety switch that is located on the high side of your AC system.
When the pressure rises too high or drops too low in your system. The High-Pressure switch will turn off your AC compressor to prevent any damage to your vehicle’s AC system.
Air Dryer
This part works together with the rest of your AC system by temporarily storing the refrigerant. This part also stores a filter for your system freeing the operation of any harmful debris and moisture that can damage your system.
Where do you find the amount of freon your vehicle’s system needs?
The amount of freon that your vehicle uses will be labeled on the data sticker located on the cross beam under the hood at the front side of your engine, in between the headlights.
What type of freon does my ac system take?
The type of freon that your vehicle uses will be located on the same data sticker your amount of refrigerant for your system is located. Newer cars have R134 refrigerant, which was the replacement system for the old R12 system.
Even though the R12 system seemed to get colder than the R134 system, the R12 system was terrible for the atmosphere. Shown through research by the EPA refrigerant being released into the atmosphere is one of the leading causes of our world’s climate change.
So, if you are looking at recycling your AC system or recharging it, and need refrigerant taken out of the system. Make sure you use the right equipment or go to an auto repair shop that has the right equipment to do the job safely.
What is recycling your ac system mean?
Recycling a vehicle’s air conditioning system takes specialized tools to complete. Using these tools, you can ensure that no refrigerant escapes the system and enters the atmosphere.
With refrigerant being one of the top leading causes to our planet’s climate change. Government departments have made it their mission to make sure all auto manufacturers and repair shops abide by the law when recycling the AC system.
Recovering your AC system consists of an AC machine or pump to evacuate all the old refrigerant in your AC system. Then it will conduct a vacuum on your system; this does multiple things.
The vacuum is below barometric pressure, so if there is a liquid or moisture in the system, it will be boiled off. All debris if there is any in the system will be vacuumed out.
Then after the vacuum has been performed, the pump will hold the pressure to ensure there is no leak in the system itself. A check valve will release any air that is found in the system. After the system shows that there is no leak in the system, the AC system will then be recharged.
The system will be charged with the correct weight of refrigerant needed for that vehicle’s system. Not all cars are alike, and pressure is disclosed by the auto manufacturer and stated on the vehicle’s data sticker.
The refrigerant is added by a calibrated scale to ensure proper weight is added. Adding too little or too much refrigerant in the system will cause the system not to run correctly, so a calibrated scale is crucial to this process.
With the R134 refrigerant, it is a no-waste refrigerant, which means all is used and reused. The recycling machine can clean Freon, and all debris, oil, air, and moisture gets flushed from the system.
After being checked by the vacuum test, the refrigerant is put back into the system. When the refrigerant cylinder is empty on the AC machine, it is then replaced by a new bottle, and the machine continues doing its job.
This was not the same recycle procedure that older systems required. Due to the R12 system being more harmful, they had their own set of specialized tools needed to evacuate and test the system.
What does recycling your ac system consist of?
Recycling your AC system consists of a pump or AC machine, pulling all the refrigerant out of the system. Running a vacuum on the system for a minimum of fifteen minutes. Then recharging the AC system with cleaned refrigerant.
What should I do if my evaporator is clogged?
When your evaporator is doing its job, it removes any heat and humidity from that hot air. Then turns it into sweet cool air we love to feel on a nice warm summer day.
With doing this, there is quite a bit of condensation that will come from your evaporator. Over time this condensation will start to build up debris and dirt clogging your drain tube.
Here are a couple of the symptom signs you will see and what you can do to correct it. Musty and mildew smell coming from your air vents. From the build-up over time, you will notice a non-consistent airflow from your vents and the terrible mildew smell will be a bold indication as well.
With the evaporator being inside your dash having access to this part can be difficult, but here is how you are going to clean that drain tube and get rid of the nasty mildew smell. In this process, you need to replace the cabin filter as well.
No need to have a dirty and disgusting cabin filter but a clean system, wouldn’t you agree? You can find a can of evaporator and heater cleaner at your local parts store or even online on Amazon.
This product will be able to clean that nasty clogged up drain tube while it is still installed on your vehicle. Remember, when using this product to read the back of the can for safety instructions.
Place your drain pan under the vehicle to catch all of the debris and chemicals that will be washed out of the drain tube, and above all else do not forget your safety glasses and gloves.
Due to the build-up in your evaporator drain tube, the mildew smell will not leave your vehicle until this problem is fixed.
What are the signs of my evaporator failing?
Your evaporator plays a crucial role in your vehicle’s AC system, but because of the change from gas to a liquid for your refrigerant in this part, it opens up the future problem of mildew and decay.
So how will you know when your evaporator is failing? Here are a couple of reliable indicators, as previously noted a strong odor when an evaporator is failing or not operating correctly could have a strong smell coming from the air vents.
This smell is not the mildew you were battling in the drain tube but refrigerant seeping out of the evaporator itself. If you have never smelt refrigerant before some would say it has a sweet aroma, but it makes my throat itchy.
When there is a leak from the evaporator, you can guarantee it will not be cooling correctly so your cool air starts to warm up and sometimes will not blow at all! Because of this leak, your Ac compressor will not engage either due to the safety switches both high and low keeping the system in check with pressures.
If you have a leak in your system, you are going to engage the low-pressure safety switch, and it will disengage your compressor to save the system from damaging itself.
Because of the condensation coming from the evaporator as stated you can guarantee mildew and decay will be there. With this part, corrosion can eat away the seals and metal, causing a leak.
When this happens, there is no repair, but only a replacement part needed to correct the system. Save yourself the time and headache of searching for this leak, here is a tip.
When auto shops recycle and recharge an AC system, they insert some oil and dye into the system to lubricate the seals, and the dye is a UV dye.
Get a UV detection kit which is a UV light with glasses that when you are in a dark place you can shine the light and wherever the system is leaking you will be able to see the leak with your light and glasses. Easy fix, find the leak and replace the part.
What are the signs that my condenser is failing?
Your condenser is your systems straight shooter; it is either working great or not working at all. If your AC system has reduced its cooling temperature substantially, then it is time you look at your condenser.
Your condenser will stop working if it is leaking or is damaged. Since your condenser at the front of your vehicle, it is not uncommon for road debris to damage the ducts and find your condenser; if this is the case with your car, then it is time to change your condenser.
If the condenser is leaking, you will notice because the condenser deals with the high-pressure gas to a high-pressure liquid so that the leak will be of high pressure.
How do I know my freon needs to be recycled?
Auto manufacturers have stated that every two years you need to have your vehicle AC system recycled and recharged.
This is not only to keep your air nice and cool for you, but auto manufacturers understand that debris can be built up in your system and to prevent damage to your system this debris needs to be evacuated.
An AC system is a very delicate piece in your engine, with the system working according to high and low pressures with safety switches intertwined having your freon clear of debris will keep that system working correctly for years to come.
So if you feel that your air is not as cold as it used to be, or you have a thermometer and your air is not at a thirty-degree difference from the outside air when putting at the max cold setting, then your system needs to be recycled and recharged.
If you do not have the specialized tools to do this repair safely, then take your vehicle to an auto repair shop that has the tools needed for this repair.
Why is there water in my passenger side floorboard?
Unlike a broken heater core, your AC systems evaporator which is located in this area will not release any liquid if it is broken.
Your AC system evaporator will only release freon if it has a rupture In one of its lines. But the drainage channel from your AC systems evaporator that does carry liquid out of the vehicle does carry liquid.
In the case that this drainage channel becomes clogged, it will leak water onto your passenger-side floorboard and will need to be replaced if found faulty.
What are the signs of a bad AC compressor?
The last thing you ever want to hear from the auto repair shop is that something is broken or not working correctly. The last thing you want to listen to that isn’t working, especially in the summer is that your AC compressor isn’t working correctly.
So here are a few of the signs you will see and hear that will be reasonable indications that your AC compressor is either not working or is on it’s way out.
The temperature in the vehicle is higher than usual or than it should be. The temperature in the car when the compressor is running correctly, and the system is fully charged is a difference of 30 degrees Fahrenheit.
A thirty-degree difference from the outside air is what your air conditioning system should be outputting. In the case that it is not reaching this temperature difference, then you should look into full system recharge.
There is no better feeling as a mechanic than to see the person’s look on their face after you fix their AC system in the middle of summer.
Loud noises are coming from the compressor when the AC clutch is engaged. These noises can come from the internal bearing that the compressor has.
Just like anything that is supposed to be moving and has a faulty bearing you will get a high pitched squeal from the compressor when the bearing is on its way out and loud grinding noise when it breaks.
AC clutch not engaging at all; this is not only a good indication but a clear indication that your AC compressor is needing to be diagnosed to see if it can be saved at all.
The most straightforward repair instead of ripping the compressor apart to diagnose is to replace the entire compressor itself.
Where can I find the correct pressure for my AC system to be at?
The correct pressure for your Ac system on your vehicle depends on the outside temperature.
Here is the pressure-temperature document; a great practice is to print the pressure document and have it laminated to connect to your AC machine or AC pump and manifold gauges.
This way, you will have the pressure chart whenever you are using the AC recycle and recharge machine.
What are the signs of a failing air dryer?
Just like the evaporator, the air dryer will have a mold smell when it is not working correctly. You can also hear rattling noise coming from the dryer as well, which is a good indication that the internal parts have come loose and are damaged to require a replacement air dryer.
Near the fittings on the air dryer, if you see leakage, this is a good sign of a failing air dryer as well. With the air dryer being not only a cleaning device of the system, but it is also temporary storage for the refrigerant, this can cause increased wear to the air dryer.
Why does my AC blow cold only when I speed up?
This is a crucial indicator that your AC system does not have the correct refrigerant charge and needs to be recycled and recharged correctly to the pressure reading chart to the outside temperature when your vehicle increases the rpm so it is increasing the pressure that the compressor can build-up in your system.
If the AC only blows cold when you speed up it is because the engine has built up enough pressure in the system to engage the pressure safety switches to engage the AC compressors clutch to turn the system on.
When you slow down, the system does not have enough pressure, and the clutch is disengaged to prevent damage to internal parts.
Why does my AC blow cold only when I slow down?
Many things in your system can cause this situation. With the vehicle blowing cold only when you slow down it could be caused by a low system charge, moisture in the system, a malfunctioning expansion valve, your system is overcharged, or a clogged evaporator.
On vehicles, the air conditioning system is very sensitive to when it comes to the pressures. So if your system is under charge or overcharged, you can guarantee that your system is not going to work correctly.
In the situation that you have a low charge, this is going to cause moisture to gather in your system with this system being so cold, especially around your evaporator.
This can cause that moisture to freeze and clog the evaporator’s fins, ceasing the evaporator from doing the job is supposed to do. The dysfunctioning expansion valve is going to happen when you have a low charge in your system.
Remember that your air conditioning system needs to have the correct pressure according to the pressure to temperature chart that was previously stated and sourced.
One last precautionary measure when it comes to keeping any mildewy or moldy scent out of vehicles the cabin is to have a clean cabin filter. These to me and changed any time that they are dirty, so they need to be checked every time you change your engine oil.
In Conclusion
A vehicle’s air conditioning system can be complicated and a worrisome project at times. But with this walkthrough guide of your vehicle’s AC system hopefully, you can diagnose your vehicle’s air conditioning problems much easier from here on out.
Remember to be safe at all times when working on your vehicle and the air conditioning system is very sensitive when it comes to its pressures.
So make sure you have the correct refrigerant, correct weight and amount of refrigerant needed in your system, and the proper pressure readings for your system. If you have all of this correct, then you are going to have some ice-cold air coming out of your air vents for years to come.
Thank you for reading my article! I hope you found it beneficial and enjoyable to read! Check out my Youtube channel and subscribe for more DIY Auto repair and flipping cars for profit videos! Thank you again, and I hope you enjoy my next piece!
