Honda has grown into one of the largest auto companies worldwide for the great value that it offers its customers. However, one of Honda’s biggest downfalls has been the quality of the Honda CRV A/C Compressor and the entire system. The Honda CRV A/C system has been noted as one of the worst A/C systems in a car because of the poor quality of the parts included in the system.
Typically, when repairing an A/C System in an automobile, one needs to completely flush the A/C system before installation and then replace both the Honda A/C Compressor and Accumulator/Drier. The Accumulator/Drier is necessary to be replaced with the Compressor as it acts as a clean filter and it prevents the new compressor from being contaminated with debris that was in the old A/C system. However, the Honda CRV system has been notorious for getting clogged in all parts of the A/C System with what has been referred to as “Black Death.” More importantly, when replacing a compressor on a CRV, one needs to prepare themselves for the proper repair of the system beyond the installation of a simple Accumulator/Drier.
The best solution to preventing “Black Death” from entering your Honda CRV’s A/C System is through a proper flush and installation of the following new A/C components:
1. Compressor
2. Condenser (with Drier attached)
3. Expansion Device
4. Evaporator
5. System Seal Kit
6. System Oil
7. Both low side and high side AC Hoses.
Honda continues to struggle to hold the CRV’s A/C System credibility. Ultimately, there is no simple answer to the Honda CRV A/C System problem. However, consumer awareness to the problem and proper repair to your CRV’s A/C system is the most logical solution to the “Black Death.”
Thus far we have covered the following auto ac parts :
1. Air Conditioning Compressor
2. Air Conditioning Condenser
3. Air Conditioning Expansion Device
If you are just now jumping into the conversation, I strongly recommend reading Parts 1-4. The topic of discussion today is the air conditioning evaporator. The ac evaporator is the first part to interact directly with the car cabin. It acts as the cabin heat exchanger. The evaporator aids the cabin air in transfering heat into the refrigerant. Ultimately, the evaporator also provides another change of state in the refrigerant, this time from liquid to gas.
When the supercooled refrigerant passes through the evaporator, the blower motor forces the passenger cabin air across the refrigerant coils and transfers the heat into the refrigerant. This superheats the liquid to a boiling point and turns the refrigerant from a liquid back into a gas.
Air Conditioning Evaporator
We have breezed through the air conditioning process via the AC compressor and onto the AC condenser. At this point in the process, the AC Orifice tube comes into play. Every air conditioning system has an orifice tube. Some have different names but their job is the same – to serve as a pressure drop device.
The orifice tube’s job is simple. It handles the highly pressurized refrigerant. Specifically, the orifice tube is responsible for reducing the refrigerant pressure. This goes hand in hand with the orifice tube’s ability to cool the refrigerant. The condenser cools the refrigerant by allowing the outside air to remove the heat. The orifice tube further cools the refrigerant down to approximately 32 degrees fahrenheit.
The drop of the temperature is the intended side effect of the drop in pressure initialized by the orifice tube. This “supercooling” of the refrigerant is needed so it can be prepared for maxumim heat absorption in the passenger department.
The pressure drop orifice tube is key because it is hard to keep the temperature at the perfect “sweet spot”. You want the temperature just high enough to prevent any moisture from freezing onto internal parts of the evaporator (more on this part later).
Now that we have an idea of the role an AC compressor plays, let’s have a look at the AC condenser. If you have ever seeing an air conditioning condenser you might have mistaken it for your car’s radiator. This is common and not surprising at at all considering the job of an Air Conditioner condenser is same as the car radiator.
The AC Condenser’s sole job is to remove the heat from the super heated refrigerant, similar to how the radiator removes the heat from the engine coolant. The AC Condenser has intricate bends and folds which pull heat out of the refrigerant as it passes through. The peculiar turns the refrigerant takes through the nooks and crannies of the ac condenser combined with outside air removes heat from the refrigerant.
The removal of heat results in a change of state in the refrigerant. When the refrigerant initially entered the ac condenser, it was a super compressed and super heated gas. When the refrigerant leaves the AC condenser, it has been cooled down enough to change states from gas to liquid upon exiting.
Air Conditioning Condenser
The auto air conditioning system is, in layman’s terms, a refrigerator with a heavily modified set up for a car. The AC Compressor is an integral part of this layout. The AC compressor’s job is to compress and circulate the ac refrigerant throughout the system; think of it as literally, the heart of the system.
There are many AC compressors out there, in my experience the Sanden AC Compressor, Denso AC Compressor, Delphi AC Compressor and AC Delco AC compressor products are ahead of the pack. These encompass max RPM up to 9000, up to 7 pistons and (Denso especially) some of the quieter, vibration free AC compressors out there.
All these ac compressor performance numbers really mean is how efficiently and quietly a compressor pumps the refrigerant through the ac system. The AC compressor does this by first putting the refrigerant under pressure before sending it to the condenser.
Hybrid principals of chemistry and physics dictate the compression of a gas makes it extremely hot. The AC compressor’s other duty is to super heat the refrigerant. You need this because for an AC system to work, the gas needs to act as a high pressure gas source which will be used later.
What happens to this super heated gas once it leaves the AC compressor? I will cover that in Part 3 as it requires the introduction of another part – the condenser.
In general, a “neighborhood” mechanic understands how the car engine works and by extension, the role a radiator, a water pump, or an oxygen sensor. What I am noticing is a car’s ac system is not general car knowledge. So here is part one of a series on car air conditioning.
This time around, I will keep it simple and answer the following question – what is auto ac?
Auto air conditioning is a combination of the following 7 components. I will go over each one in greater detail in subsequent posts.
1. AC Compressor
2. AC Condenser
3. Orifice Tube
4. AC Evaporator
5. AC Receiver / Drier
6. AC Lines & Hoses
7. AC Blower Motor
So someone asked if I had some PAG oil for their AC Compressor. I asked what type and how much they needed. They said they had no idea and asked if it even mattered. Wow!
I’ve talked about this before. It is very important to get the correct oil for your vehicle. A Chrylser ac compressor takes entirely different oil than a Suzuki XL7 Compressor. They simply are not interchangeable, you have to be exact.
You need lookup the AC oil chart and see what is required for your vehicle. Putting in too little oil can result in burning out the compressor bearings. Putting in too much oil can reduce the perfomance of the system. The wrong oil can also cause compressors to burn out.
So we’re finally in April, easter is coming and the weather is getting warmer. The one thing that always coming to mind is the need for Air Conditioning and the frequent failure of A/C Compressors.
There is not much maintenance you can do. These systems do unbeliveable amount of work and are constantly failing. You can service your A/C every 100,000 miles by having them flush, replace the ac drier and add new oil and freon. The new oil and clean system will help, but thats about it.
You will want make sure you replace the ac compressor and the a/c drier, these are both very important. The drier is the filter on the system and needs to be replaced. I have
I always get questions about Automotive A/C Compressor Electrical connections. What wire is ground? What wire is power? Plug changing? and so on and so on.
The first thing to know is that every manufacturer is different. Sanden ac compressor almost always has 2 wires coming out of the clutch coil. The question is always which is ground and which is power. The answer is that is doesn’t matter. Its just a loop, so you can power either one. This is true of almost all 12 volt systems. 24 volt for industrial applications will need to be looked at individually.
Many manufacturers like Visteon, Denso and Delphi use hard mounted plugs. See the picture below. This Ford AC Compressor made by Visteon has a fixed plug on it. You can see it just next to the belt. You will need to replace with the identical one. No getting around this. They do make some adapters, but you are pushing it at that point. They better have been tested to work on that application.
Most compressors come without the correct plug, this is an easy swap. Just cut the wires and swap the plug over.
What is an R4 air conditioning compressor and why is it used? Good question, but probably too much to answer here.
A rotary style compressor rotates internally at high speed to compressor the liquid refrigerant. The use of the spinning crank shaft enabled it to work fairly well and dramatically shrunk the size of compressors. It became popular in the 1980’s as a smaller, more energy efficient way to build an ac compressor.
Seen in the picture of the Chevrolet Suburban Compressor, rotary compressors were common in the mid to late 1980’s and up to the mid 1990’s. After that, the same idea of rotation was used, but in different ways. The were able to make them smaller, or use series of them to improve performance.
Today, the rotary compressor is still in use in many applications.
